On 13/11/2022 13:42, Andrew Gabriel wrote:
> On 11/11/2022 17:04, charles wrote:
>> I don't see "greatly increase your 24/7 energy consumption" the only
>> consumtion would be keeping a couple of NiCad Cells trickle charged.
>
> They don't trickle charge - they charge at quite a high rate so they're
> fully charged for use again quickly.

Just look at the specifications for many of these lights - they take 24
hours to charge from the discharge state.

The ones I have don't have any
> smarts inside to reduce the charging current when the batteries are
> fully charged, and they use special high temperature batteries which can
> stand a continuous high current charge rate.

The majority still use nicad.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

In article <ZKmcnWkxMP2Lt-z-nZ2dnZfqlJ_8fwAA@giganews.com>,
Colin Bignell <cpb@bignellREMOVETHIS.me.uk> wrote:
> On 13/11/2022 16:25, Robin wrote:
> > On 13/11/2022 13:33, Tim Streater wrote:
> >> On 13 Nov 2022 at 09:01:21 GMT, SH <i.love.spam@spam.com> wrote:
> >>
> >>> I have balance problems, very early cataracts ...
> >>
> >> If cataracts are manifest and an optahmologist agrees, then you should
> >> get
> >> them fixed immediately. There's no reason at all to delay. The
> >> opthamologist > can put you in for treatment.
> >>
> >
> > I consider the risks involved in surgery for cataracts good reason to
> > delay if cataracts are not having a significant effect. The NHS say
> > "There is a very small risk — around 1 in 1,000 — of permanent sight
> > loss in the treated eye as a direct result of the operation."[1] The
> > risk may well be smaller with private treatment but it ain't going to be
> > nil.

> I'm not sure that the risk will be any different. My late partner had
> her first cataract operation done privately. A few years later, when the
> NHS waiting times were more reasonable, she had the second done on the
> NHS. Both were done by the same surgeon.

SWMBO had both eyes done (3 weeks apart) last November. - privately. The
surgeon was also the NHS Consultant who she'd been seeing on the NHS, but
the waiting time for private was only weeks not months or years on the NHS.

> >
> > I was advised of evidence of cataracts 4 years ago. My acuity is not
> > what it was but at 6/6 is good enough for me to drive and to carry out
> > the other activities I wish to continue. I do not yet have trouble in
> > low light - except for reading and close work - or when driving at
> > night. So that's 4 years of binocular vision I might have lost if I'd
> > opted for surgery straight away.
> >
> > There's also the fact that the NHS will treat only if cataracts affect
> > quality of life. So cost can be a reason to wait.
> >
> > [1] https://www.nhs.uk/conditions/cataract-surgery/
> >

> --
> Colin

--
from KT24 in Surrey, England - sent from my RISC OS 4té
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

On 13/11/2022 09:01, SH wrote:

> ground floor is 42 off 4 watt bulbs = 168 watts max load.
>
> 1st floor is 23 off 4 watt bulbs so thats 96 watts max load.

Small down-lighters by any chance? You would probably improve the
illumination greatly by using LED panel lighting. I don't necessarily
mean ceiling tile type as used in offices but more of the designer type
more fitted to a domestic environment, and not at a great cost.

>
> loft is two flourries currently but can change this. (I know this one
> sounds daft but it was done for the day when we have a loft conversion
> and made into a full lighting circuit)

Why bother changing these if you haven't converted to the loft. How
often do you use the loft and would you need to go up there in an
emergency requiring emergency lighting.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 13/11/2022 16:54, charles wrote:

> Now, the cataract has suddenly grown - co-incidental with my getting Covid
> - and I have an NHS appointment at a private eye hospital in 10 days time.
> This was only arranged during last week. I'm told that there will only be a
> 4 -6 week wait for an operation.
>
> I'm going for it

I had one eye done earlier this year under the NHS in a private
hospital. My appointment time was 8:30 but turned up at 8:15. In the
theatre at 9:00 for 10 minutes of mild discomfort and I was back home by
9:45. However, I was first on the list - there were 7 others having the
pre-treatment (multiple lots of eye drops) at the same times as me so
they will have been in the hospital a bit longer.

Slightly blurry eyesight in the one eye for the rest of the day but
vastly improved overnight. I left driving for another 24hours.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 13/11/2022 18:11, SH wrote:

>
> someone mentioned the other day that if you have solar PV and a power
> wall fitted, you can have backup power if there is an external power
> interruption and the house then becomes islanded? Is this true? If aom
> what is the typical kVA and typical runtime of the battery if sized for
> a 5kWp array?

The average household uses 8.5kWh a day (assuming gas/oil central heating)

If you have a power wall you could charge it up from the grid while the
power is still on and in a power cut run on a 10KWh battery for a day.

You appear to be looking att more and more expensive solutions for what
may be achieved much cheaper if its just for emergency lighting for a
few hours.

You may have eyesight problem that require high levels of illumination
for normal day to day comfortable living but do you really need this
level of illumination during a relatively short power cut? A single 5W
led emergency light can fully illuminate a room fairly brightly.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 13/11/2022 19:23, alan_m wrote:
> On 13/11/2022 09:01, SH wrote:
>
>> ground floor is 42 off 4 watt bulbs = 168 watts max load.
>>
>> 1st floor is 23 off 4 watt bulbs so thats 96 watts max load.
>
> Small down-lighters by any chance? You would probably improve the
> illumination greatly by using LED panel lighting. I don't necessarily
> mean ceiling tile type as used in offices but more of the designer type
> more fitted to a domestic environment, and not at a great cost.

Most of the lightbulbs in use are SES candle bulbs or GU10 spotlights.
all 4watt LEDs

>> loft is two flourries currently but can change this. (I know this one
>> sounds daft but it was done for the day when we have a loft conversion
>> and made into a full lighting circuit)
>
> Why bother changing these if you haven't converted to the loft. How
> often do you use the loft and would you need to go up there in an
> emergency requiring emergency lighting.

Its also the computer servers, media servers and CCTV room for the whole
house..... :-)

In each room put the emergency light on the same circuit as its light.

Then if its light rcd/mcb/fuse is the only one to trip the emergency light will go on.

[g]

On Friday, November 11, 2022 at 2:27:13 PM UTC, SH wrote:
> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
> Garage lighting circuit and a Loft lighting circuit on 4 off 6A RCBOs.
>
> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO that is
> present in EVERY room (16 interlinked detectors.)
>
> Now I want to fit an emergency light to every room ceiling
>
> So thus I can wire either into the exisiting detector for that room or
> the ceiling light fitting in the room.
>
> Now my question for discussion: WHich is more sensible and why?
>
> If it makes any difference some rooms (garage / loft / downstairs shower
> room) have no windows.
>
>
>
> Stephen.

On 13/11/2022 18:44, charles wrote:
> In article <ZKmcnWkxMP2Lt-z-nZ2dnZfqlJ_8fwAA@giganews.com>,
> Colin Bignell <cpb@bignellREMOVETHIS.me.uk> wrote:
>> On 13/11/2022 16:25, Robin wrote:
>>> On 13/11/2022 13:33, Tim Streater wrote:
>>>> On 13 Nov 2022 at 09:01:21 GMT, SH <i.love.spam@spam.com> wrote:
>>>>
>>>>> I have balance problems, very early cataracts ...
>>>>
>>>> If cataracts are manifest and an optahmologist agrees, then you should
>>>> get
>>>> them fixed immediately. There's no reason at all to delay. The
>>>> opthamologist > can put you in for treatment.
>>>>
>>>
>>> I consider the risks involved in surgery for cataracts good reason to
>>> delay if cataracts are not having a significant effect. The NHS say
>>> "There is a very small risk — around 1 in 1,000 — of permanent sight
>>> loss in the treated eye as a direct result of the operation."[1] The
>>> risk may well be smaller with private treatment but it ain't going to be
>>> nil.
>
>> I'm not sure that the risk will be any different. My late partner had
>> her first cataract operation done privately. A few years later, when the
>> NHS waiting times were more reasonable, she had the second done on the
>> NHS. Both were done by the same surgeon.
>
> SWMBO had both eyes done (3 weeks apart) last November. - privately. The
> surgeon was also the NHS Consultant who she'd been seeing on the NHS, but
> the waiting time for private was only weeks not months or years on the NHS.

A 14 moth NHS wait is why I paid for the first one. By the time the
second needed doing, the NHS wait was only a few weeks.

>
>
>>>
>>> I was advised of evidence of cataracts 4 years ago. My acuity is not
>>> what it was but at 6/6 is good enough for me to drive and to carry out
>>> the other activities I wish to continue. I do not yet have trouble in
>>> low light - except for reading and close work - or when driving at
>>> night. So that's 4 years of binocular vision I might have lost if I'd
>>> opted for surgery straight away.
>>>
>>> There's also the fact that the NHS will treat only if cataracts affect
>>> quality of life. So cost can be a reason to wait.
>>>
>>> [1] https://www.nhs.uk/conditions/cataract-surgery/
>>>
>
>> --
>> Colin
>

--
Colin Bignell

On 11/11/2022 14:27, SH wrote:
> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
> Garage lighting circuit and a Loft lighting circuit on 4 off 6A RCBOs.
>
> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO that is
> present in EVERY room (16 interlinked detectors.)
>
> Now I want to fit an emergency light to every room ceiling
>
> So thus I can wire either into the exisiting detector for that room or
> the ceiling light fitting in the room.
>
> Now my question for discussion:   WHich is more sensible and why?
>
> If it makes any difference some rooms (garage / loft / downstairs shower
> room) have no windows.
>
>
>
> Stephen.
maintained or non-maintained ? ....

On 13/11/2022 20:00, SH wrote:

>>
>> Small down-lighters by any chance? You would probably improve the
>> illumination greatly by using LED panel lighting. I don't necessarily
>> mean ceiling tile type as used in offices but more of the designer
>> type more fitted to a domestic environment, and not at a great cost.
>
> Most of the lightbulbs in use are SES candle bulbs or GU10 spotlights.
> all 4watt LEDs

Probably the worst type of lighting for anyone that has sight issues.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On Mon, 14 Nov 2022 04:32:06 +1100, Colin Bignell
<cpb@bignellremovethis.me.uk> wrote:

> On 13/11/2022 16:25, Robin wrote:
>> On 13/11/2022 13:33, Tim Streater wrote:
>>> On 13 Nov 2022 at 09:01:21 GMT, SH <i.love.spam@spam.com> wrote:
>>>
>>>> I have balance problems, very early cataracts ...
>>>
>>> If cataracts are manifest and an optahmologist agrees, then you should
>>> get
>>> them fixed immediately. There's no reason at all to delay. The
>>> opthamologist > can put you in for treatment.
>>>
>> I consider the risks involved in surgery for cataracts good reason to
>> delay if cataracts are not having a significant effect. The NHS say
>> "There is a very small risk – around 1 in 1,000 – of permanent sight
>> loss in the treated eye as a direct result of the operation."[1] The
>> risk may well be smaller with private treatment but it ain't going to
>> be nil.

> I'm not sure that the risk will be any different.

While that is true, having it done when you have unacceptible
downsides with the cataracts does ensure that you do have
acceptable vision in those eyes before risking anything.

> My late partner had her first cataract operation done privately. A few
> years later, when the NHS waiting times were more reasonable, she had
> the second done on the NHS. Both were done by the same surgeon.
>
>
>> I was advised of evidence of cataracts 4 years ago. My acuity is not
>> what it was but at 6/6 is good enough for me to drive and to carry out
>> the other activities I wish to continue. I do not yet have trouble in
>> low light - except for reading and close work - or when driving at
>> night. So that's 4 years of binocular vision I might have lost if I'd
>> opted for surgery straight away.
>> There's also the fact that the NHS will treat only if cataracts affect
>> quality of life. So cost can be a reason to wait.
>> [1] https://www.nhs.uk/conditions/cataract-surgery/
>>

On Friday, 11 November 2022 at 14:27:13 UTC, SH wrote:
> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
> Garage lighting circuit and a Loft lighting circuit on 4 off 6A RCBOs.
>
> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO that is
> present in EVERY room (16 interlinked detectors.)
>
> Now I want to fit an emergency light to every room ceiling
>
> So thus I can wire either into the exisiting detector for that room or
> the ceiling light fitting in the room.
>
> Now my question for discussion: WHich is more sensible and why?
>
> If it makes any difference some rooms (garage / loft / downstairs shower
> room) have no windows.
>
>
>
> Stephen.

One thing I learnt about backup lighting is that none are long term reliable. Gas lights are, and they're cheap.

On Mon, 14 Nov 2022 06:38:53 +1100, alan_m <junk@admac.myzen.co.uk> wrote:

> On 13/11/2022 16:54, charles wrote:
>
>> Now, the cataract has suddenly grown - co-incidental with my getting
>> Covid
>> - and I have an NHS appointment at a private eye hospital in 10 days
>> time.
>> This was only arranged during last week. I'm told that there will only
>> be a
>> 4 -6 week wait for an operation.
>> I'm going for it
>
> I had one eye done earlier this year under the NHS in a private
> hospital. My appointment time was 8:30 but turned up at 8:15. In the
> theatre at 9:00 for 10 minutes of mild discomfort and I was back home by
> 9:45. However, I was first on the list - there were 7 others having the
> pre-treatment (multiple lots of eye drops) at the same times as me so
> they will have been in the hospital a bit longer.
>
> Slightly blurry eyesight in the one eye for the rest of the day but
> vastly improved overnight. I left driving for another 24hours.

What did they do about need for glasses afterwards ?

I initially thought that it couldnt be possible to have the new fixed focus
lens never need any glasses, but turns out its more complicated than that.

My BiL had his done just after Xmas last year and does need
reading glasses but they claim that the surgeon stuffed that up.

I need mine done but I deferred it due to covid, and then the
bugger who used to show up in my town doing it retired.

There is now a new one showing up but we are just getting
a new covid surge so I'd rather wait till that is over.

The only downside with my quite severe cataracts is that I can't
get my drivers license renewed because we have to be able to
read the right line on the eye chart and I can't do that reliably
although I can still drive fine and occassionally do that illegally.

On 13/11/2022 20:24, Jim Stewart ... wrote:
> On 11/11/2022 14:27, SH wrote:
>> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
>> Garage lighting circuit and a Loft lighting circuit on 4 off 6A RCBOs.
>>
>> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO that
>> is present in EVERY room (16 interlinked detectors.)
>>
>> Now I want to fit an emergency light to every room ceiling
>>
>> So thus I can wire either into the exisiting detector for that room or
>> the ceiling light fitting in the room.
>>
>> Now my question for discussion:   WHich is more sensible and why?
>>
>> If it makes any difference some rooms (garage / loft / downstairs
>> shower room) have no windows.
>>
>>
>>
>> Stephen.
> maintained or non-maintained ? ....

The emergency lights I have been looking at have a jumper internallt so
you can switch between maintained and non-maintained.

S.

On 13/11/2022 13:42, Andrew Gabriel wrote:
> On 11/11/2022 17:04, charles wrote:
>> I don't see "greatly increase your 24/7 energy consumption" the only
>> consumtion would be keeping a couple of NiCad Cells trickle charged.
>
> They don't trickle charge - they charge at quite a high rate so they're
> fully charged for use again quickly. The ones I have don't have any
> smarts inside to reduce the charging current when the batteries are
> fully charged, and they use special high temperature batteries which can
> stand a continuous high current charge rate.

A dumb one that has a ~fixed 15v supply in series with a resistor will
not quite murder the battery but it isn't very good for it either.

Charge rate is always (V_in-Vbatt)/R

So it varies between (15-10.8)/R = 4.2/R (flat) to (15-14.4)/R = 0.6R
when fully charged. However the supply voltage also tends to rise a bit
when the current draw deceases. Most do have a discharge cutoff limit to
avoid damaging the battery by too low a terminal voltage.

They do vary a lot. Only the cheapest and nastiest have no measures at
all to protect the typically SLA battery from harm. Mine have a pretty
crude diode arrangement so that from nearly flat the diodes conduct and
it quickly charges at C/3 to a terminal voltage of about 14v then the
diodes stop conducting and a bleed resistor tops it off at C/20 ish.

The whole thing is made a bit more complicated by the way output voltage
of the rectified AC rises as the current drawn falls. ie

_______|r|_____________|R|______
V_in | |_____ I_out, V_out==V_batt
|---|>|---|>|---|

Once V_batt gets to 14v the parallel diode stops conducting.

Initial charge rate when flat = (V_in-V_batt-1.2)/r

Final trickle charge = (V_in-Vbatt)/(R+r)

R ~ 15r

> So several of them will start costing you in electricity use.

I only have previous generation iron transformers (ie fluoro not LED
based ones) and they each draw about 5W continuously when they are on
and warm to the touch (and produce about 20W of fluoro light when the
mains fails). They are warmer when the inverter is actually running.

NB Cheapest and nastiest UPS devices can only just about survive running
at maximum load for the length of time that their battery can provide for.

> I rolled my own in a few rooms which run from a 12V alarm supply, and
> use the alarm motion sensors as occupancy sensors so they're only on
> when mains fails, it's dark, and there's movement in the room. These
> don't add anything to the base load except for a single mains relay
> (probably about ½watt) which signals to the controller if lighting
> circuit mains power is on or not. (The controller does have its own
> mains fail detection, but it's got a 30 second delay to filter out short
> glitches, so not ideal for emergency lighting switching.)

In the interests of true DIY solutions then if you can solder then 3
white 3W LEDs in series onto a heat sink and a ~15v wall wart to charge
an SLA in a similar configuration to as described above with a relay to
hold the LED circuit open whilst there is mains would be a DIY option.

At 1A a 7Ah SLA will last a good 6h or so of intermittent use.

--
Regards,
Martin Brown

On 13/11/2022 13:36, John Rumm wrote:
> On 13/11/2022 09:01, SH wrote:
>> On 12/11/2022 18:47, John Rumm wrote:
>>> On 12/11/2022 06:30, John J wrote:
>>>> On Friday, 11 November 2022 at 14:27:13 UTC, SH wrote:
>>>>> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
>>>>> Garage lighting circuit and a Loft lighting circuit on 4 off 6A RCBOs.
>>>>>
>>>>> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO
>>>>> that is
>>>>> present in EVERY room (16 interlinked detectors.)
>>>>>
>>>>> Now I want to fit an emergency light to every room ceiling
>>>>>
>>>>> So thus I can wire either into the exisiting detector for that room or
>>>>> the ceiling light fitting in the room.
>>>>>
>>>>> Now my question for discussion: WHich is more sensible and why?
>>>>>
>>>>> If it makes any difference some rooms (garage / loft / downstairs
>>>>> shower
>>>>> room) have no windows.
>>>>>
>>>>>
>>>>>
>>>>> Stephen.
>>>
>>>> I know my way around our house in the dark.
>>>
>>> Not going to make a good epitaph thought is it?
>>>
>>> Can you do it when just woken, in smoke, when drunk etc. Your life
>>> may depend on the answer.
>>>
>>> Now can everyone else in the house, including guests that are not so
>>> familiar with the layout.
>>>
>>>> There's a torch kept near the consumer unit. While I don't disagree
>>>> that emergency lights are handy you do sound a bit obsessive.
>>>
>>> Every room - perhaps, but then again we don't actually know what the
>>> OPs requirements and needs are.
>>>
>>
>>
>>
>> I have balance problems, very early cataracts and poor eyesight
>> contrast sensitivity so a torch in a room simply does not cut it.
>>
>> The whole room needs to be lit during a power cut to keep myself safe.
>> (The vestibular system relies on eyesight too believe it or not, and
>> my eyesight sensitivity means I can't pick out objects visually and my
>> cataracts means I have to have higher levels of illumination.
>
> Good points and well made :-)
>
>> It strikes me it would be more cost effective to put 4 bigger battery
>> packs next to the home CU to do the 4 lighting circuits (ground, 1st
>> floor, Loft and garage/outside lights than it is to go round every
>> single light fitting poking in inverters and Li Ion batteries.....
>>
>> (Quick mentral calculation:
>>
>> ground floor is 42 off 4 watt bulbs = 168 watts max load.
>>
>> 1st floor is 23 off 4 watt bulbs so thats 96 watts max load.
>>
>> loft is two flourries currently but can change this. (I know this one
>> sounds daft but it was done for the day when we have a loft conversion
>> and made into a full lighting circuit)
>>
>> The garage/outside is 2 flourries (can change), 2.4 m LED batten and
>> 14 10w or 20w LED floods and 5 5 LED bulbs.
>>
>> SO have wondered about using some computer UPS next to consumer unit
>> but I don't think an UPS would last for 3 hours or more unless anyone
>> knows different?
>
> In total load terms that is not a huge amount. Yes a UPS will do the
> trick. What you tend to find with most "integrated" UPS devices is they
> have battery capacity to provide a few mins of support at full load, and
> then the time extends at lower loads. However for many there is an upper
> limit on run time due to the parasitic losses running the inverter. So
> You might get an hour and a half out of a large one - but that would be
> the run time even with no external load at all.
>
> The solution is to move away from integrated UPS solutions where the
> only battery capacity available is that which is contained in the box,
> to one where you can add additional capacity.
>
> At it's simplest level this might be by modding a normal integrated one
> with more batteries, or looking at slightly more commercially focussed
> options. Then you can usually design not only the load you need to
> support, but also the run time you need.
>
> Many of the UPS vendors sites have selection tools that let you specify
> the load and run time, and they can offer product combinations that match.
>
> e.g. start with:
>
> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-1000VA-230V-with-Extended-Runtime-Battery-Pack/P-SRV1KIL
>
> Add another *two* of these:
>
> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-Battery-Pack-1kVA-for-Extended-Runtime-Model-36V-648VAh/P-SRV36BP-9A
>
> That gets you more than 4 hours at full load.
>
>
>

Actually thinking about this a bit more.....

What about a 2nd 63A CU that is fed by a UPS with extra battery and the
UPS is then connected to a standby generator.

The low amperage circuits like lighting, alarm, CCTV, smoke dets and
boiler are then wired through a DPDT relay (one for each RCBO) with the
relay coil energised by the original CU.

When power fails, the bank of changeover DPDT relays then switch the low
current circuits over to the 2nd CU (which have the same RCBO's
duplicated for each circuit) and this secondary CU is connected to the
UPS and Genny.

This then allows instant switchover of all lighting circuits and smoke
dets, boiler, CCTV and alarm to UPS and my route to the generator
location is fully lit to allow me to to then start the genny and then
the UPS can then be energised back up to through powering rather than
discharging its batteries.

(I need the outside floods to see my way across the garden to get wood
from the woodstore for the woodburner)

From an IET wiring regs point of is the above permissible with warning
labels on both CUs about some circuits being energised during a power
cut? It no different to a PV array with a battery is it really?

On 13/11/2022 16:38, Colin Bignell wrote:
> On 13/11/2022 13:30, Robin wrote:
>> On 13/11/2022 09:01, SH wrote:
>>
>> <snip>
>>
>>>
>>> The whole room needs to be lit during a power cut to keep myself
>>> safe. (The vestibular system relies on eyesight too believe it or
>>> not, and my eyesight sensitivity means I can't pick out objects
>>> visually and my cataracts means I have to have higher levels of
>>> illumination.
>>>
>>
>> Is it essential that you have a system which cuts in automatically if
>> power cuts off?  Or would you settle for one which you could turn on
>> manually when there is a power cut (or in advance of a scheduled cut)?
>
> Which could be difficult to find in darkness with vision problems.
>

Good grief. Cant you feel your way to a torch by your bed?

--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

On 14/11/2022 12:15, The Natural Philosopher wrote:
> On 13/11/2022 16:38, Colin Bignell wrote:
>> On 13/11/2022 13:30, Robin wrote:
>>> On 13/11/2022 09:01, SH wrote:
>>>
>>> <snip>
>>>
>>>>
>>>> The whole room needs to be lit during a power cut to keep myself
>>>> safe. (The vestibular system relies on eyesight too believe it or
>>>> not, and my eyesight sensitivity means I can't pick out objects
>>>> visually and my cataracts means I have to have higher levels of
>>>> illumination.
>>>>
>>>
>>> Is it essential that you have a system which cuts in automatically if
>>> power cuts off?  Or would you settle for one which you could turn on
>>> manually when there is a power cut (or in advance of a scheduled cut)?
>>
>> Which could be difficult to find in darkness with vision problems.
>>
>
> Good grief. Cant you feel your way to a torch by your bed?
To find a torch, all I need to do is reach into my breast pocket (or on
the bedside table if I am in bed) for my mobile phone. Rechargeable
torches hang by the front door and I could find those by the light of
the emergency light over the stairwell.

However, moving around my house in total darkness would be hazardous.
Far too may things to walk into or trip over and I certainly wouldn't
want to get my toe caught in one of the rat traps I always keep set,
even when I don't know any rodents are around.

--
Colin Bignell

On 13/11/2022 18:11, SH wrote:
> On 13/11/2022 13:36, John Rumm wrote:
>> On 13/11/2022 09:01, SH wrote:
>>> On 12/11/2022 18:47, John Rumm wrote:
>>>> On 12/11/2022 06:30, John J wrote:
>>>>> On Friday, 11 November 2022 at 14:27:13 UTC, SH wrote:
>>>>>> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
>>>>>> Garage lighting circuit and a Loft lighting circuit on 4 off 6A
>>>>>> RCBOs.
>>>>>>
>>>>>> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO
>>>>>> that is
>>>>>> present in EVERY room (16 interlinked detectors.)
>>>>>>
>>>>>> Now I want to fit an emergency light to every room ceiling
>>>>>>
>>>>>> So thus I can wire either into the exisiting detector for that
>>>>>> room or
>>>>>> the ceiling light fitting in the room.
>>>>>>
>>>>>> Now my question for discussion: WHich is more sensible and why?
>>>>>>
>>>>>> If it makes any difference some rooms (garage / loft / downstairs
>>>>>> shower
>>>>>> room) have no windows.
>>>>>>
>>>>>>
>>>>>>
>>>>>> Stephen.
>>>>
>>>>> I know my way around our house in the dark.
>>>>
>>>> Not going to make a good epitaph thought is it?
>>>>
>>>> Can you do it when just woken, in smoke, when drunk etc. Your life
>>>> may depend on the answer.
>>>>
>>>> Now can everyone else in the house, including guests that are not so
>>>> familiar with the layout.
>>>>
>>>>> There's a torch kept near the consumer unit. While I don't disagree
>>>>> that emergency lights are handy you do sound a bit obsessive.
>>>>
>>>> Every room - perhaps, but then again we don't actually know what the
>>>> OPs requirements and needs are.
>>>>
>>>
>>>
>>>
>>> I have balance problems, very early cataracts and poor eyesight
>>> contrast sensitivity so a torch in a room simply does not cut it.
>>>
>>> The whole room needs to be lit during a power cut to keep myself
>>> safe. (The vestibular system relies on eyesight too believe it or
>>> not, and my eyesight sensitivity means I can't pick out objects
>>> visually and my cataracts means I have to have higher levels of
>>> illumination.
>>
>> Good points and well made :-)
>>
>>> It strikes me it would be more cost effective to put 4 bigger battery
>>> packs next to the home CU to do the 4 lighting circuits (ground, 1st
>>> floor, Loft and garage/outside lights than it is to go round every
>>> single light fitting poking in inverters and Li Ion batteries.....
>>>
>>> (Quick mentral calculation:
>>>
>>> ground floor is 42 off 4 watt bulbs = 168 watts max load.
>>>
>>> 1st floor is 23 off 4 watt bulbs so thats 96 watts max load.
>>>
>>> loft is two flourries currently but can change this. (I know this one
>>> sounds daft but it was done for the day when we have a loft
>>> conversion and made into a full lighting circuit)
>>>
>>> The garage/outside is 2 flourries (can change), 2.4 m LED batten and
>>> 14 10w or 20w LED floods and 5 5 LED bulbs.
>>>
>>> SO have wondered about using some computer UPS next to consumer unit
>>> but I don't think an UPS would last for 3 hours or more unless anyone
>>> knows different?
>>
>> In total load terms that is not a huge amount. Yes a UPS will do the
>> trick. What you tend to find with most "integrated" UPS devices is
>> they have battery capacity to provide a few mins of support at full
>> load, and then the time extends at lower loads. However for many there
>> is an upper limit on run time due to the parasitic losses running the
>> inverter. So You might get an hour and a half out of a large one - but
>> that would be the run time even with no external load at all.
>>
>> The solution is to move away from integrated UPS solutions where the
>> only battery capacity available is that which is contained in the box,
>> to one where you can add additional capacity.
>>
>> At it's simplest level this might be by modding a normal integrated
>> one with more batteries, or looking at slightly more commercially
>> focussed options. Then you can usually design not only the load you
>> need to support, but also the run time you need.
>>
>> Many of the UPS vendors sites have selection tools that let you
>> specify the load and run time, and they can offer product combinations
>> that match.
>>
>> e.g. start with:
>>
>> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-1000VA-230V-with-Extended-Runtime-Battery-Pack/P-SRV1KIL
>>
>> Add another *two* of these:
>>
>> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-Battery-Pack-1kVA-for-Extended-Runtime-Model-36V-648VAh/P-SRV36BP-9A
>>
>> That gets you more than 4 hours at full load.
>>
>>
>>
>
>
> the cost of the UPS and extra batteries is more shocking than my
> electricity bill!!!!   :-D

Well as you move to more commercial targeted kit, you tend to get more
commercial prices!

> mind you its been ages since I bought an UPS, the last one was a 750VA
> unit for around £100.

To be fair my example was a bit excessive - you don't need 4 hours at
full load, and it may be that a smaller power UPS with external batts is
available - that was what came to hand quickly. Even a cheap 450VA UPS
hooked up to much bigger than usual SLA batts (mounted externally) might
do the trick. (assuming they inverter does not have a temperature
profile that limits max run time)

> someone mentioned the other day that if you have solar PV and a power
> wall fitted, you can have backup power if there is an external power
> interruption and the house then becomes islanded? Is this true? If aom
> what is the typical kVA and typical runtime of the battery if sized for
> a 5kWp array?

Your bog standard Solar PV will use a grid tied inverter, and so can't
function without mains power. More sophisticated systems designed to
time shift consumption however should be able to work without external
power.

There is no easy answer to the sizing / run time questions since they
are interdependent. The KVA is more related to max the power of the
inverter rather than the battery (assuming it can provide adequate
current to meet the power demand of the inverter). The run time is
dependant on the capacity of the batts, and the load on the inverter.

--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

On 14/11/2022 08:38, SH wrote:
> On 13/11/2022 20:24, Jim Stewart ... wrote:
>> On 11/11/2022 14:27, SH wrote:
>>> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
>>> Garage lighting circuit and a Loft lighting circuit on 4 off 6A RCBOs.
>>>
>>> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO that
>>> is present in EVERY room (16 interlinked detectors.)
>>>
>>> Now I want to fit an emergency light to every room ceiling
>>>
>>> So thus I can wire either into the exisiting detector for that room
>>> or the ceiling light fitting in the room.
>>>
>>> Now my question for discussion:   WHich is more sensible and why?
>>>
>>> If it makes any difference some rooms (garage / loft / downstairs
>>> shower room) have no windows.
>>>
>>>
>>>
>>> Stephen.
>> maintained or non-maintained ? ....
>
>
> The emergency lights I have been looking at have a jumper internallt so
> you can switch between maintained and non-maintained.
>
> S.
oh goody

On Monday, 14 November 2022 at 14:17:44 UTC, John Rumm wrote:
> On 13/11/2022 18:11, SH wrote:
> > On 13/11/2022 13:36, John Rumm wrote:
> >> On 13/11/2022 09:01, SH wrote:
> >>> On 12/11/2022 18:47, John Rumm wrote:
> >>>> On 12/11/2022 06:30, John J wrote:
> >>>>> On Friday, 11 November 2022 at 14:27:13 UTC, SH wrote:
> >>>>>> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
> >>>>>> Garage lighting circuit and a Loft lighting circuit on 4 off 6A
> >>>>>> RCBOs.
> >>>>>>
> >>>>>> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO
> >>>>>> that is
> >>>>>> present in EVERY room (16 interlinked detectors.)
> >>>>>>
> >>>>>> Now I want to fit an emergency light to every room ceiling
> >>>>>>
> >>>>>> So thus I can wire either into the exisiting detector for that
> >>>>>> room or
> >>>>>> the ceiling light fitting in the room.
> >>>>>>
> >>>>>> Now my question for discussion: WHich is more sensible and why?
> >>>>>>
> >>>>>> If it makes any difference some rooms (garage / loft / downstairs
> >>>>>> shower
> >>>>>> room) have no windows.
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> Stephen.
> >>>>
> >>>>> I know my way around our house in the dark.
> >>>>
> >>>> Not going to make a good epitaph thought is it?
> >>>>
> >>>> Can you do it when just woken, in smoke, when drunk etc. Your life
> >>>> may depend on the answer.
> >>>>
> >>>> Now can everyone else in the house, including guests that are not so
> >>>> familiar with the layout.
> >>>>
> >>>>> There's a torch kept near the consumer unit. While I don't disagree
> >>>>> that emergency lights are handy you do sound a bit obsessive.
> >>>>
> >>>> Every room - perhaps, but then again we don't actually know what the
> >>>> OPs requirements and needs are.
> >>>>
> >>>
> >>>
> >>>
> >>> I have balance problems, very early cataracts and poor eyesight
> >>> contrast sensitivity so a torch in a room simply does not cut it.
> >>>
> >>> The whole room needs to be lit during a power cut to keep myself
> >>> safe. (The vestibular system relies on eyesight too believe it or
> >>> not, and my eyesight sensitivity means I can't pick out objects
> >>> visually and my cataracts means I have to have higher levels of
> >>> illumination.
> >>
> >> Good points and well made :-)
> >>
> >>> It strikes me it would be more cost effective to put 4 bigger battery
> >>> packs next to the home CU to do the 4 lighting circuits (ground, 1st
> >>> floor, Loft and garage/outside lights than it is to go round every
> >>> single light fitting poking in inverters and Li Ion batteries.....
> >>>
> >>> (Quick mentral calculation:
> >>>
> >>> ground floor is 42 off 4 watt bulbs = 168 watts max load.
> >>>
> >>> 1st floor is 23 off 4 watt bulbs so thats 96 watts max load.
> >>>
> >>> loft is two flourries currently but can change this. (I know this one
> >>> sounds daft but it was done for the day when we have a loft
> >>> conversion and made into a full lighting circuit)
> >>>
> >>> The garage/outside is 2 flourries (can change), 2.4 m LED batten and
> >>> 14 10w or 20w LED floods and 5 5 LED bulbs.
> >>>
> >>> SO have wondered about using some computer UPS next to consumer unit
> >>> but I don't think an UPS would last for 3 hours or more unless anyone
> >>> knows different?
> >>
> >> In total load terms that is not a huge amount. Yes a UPS will do the
> >> trick. What you tend to find with most "integrated" UPS devices is
> >> they have battery capacity to provide a few mins of support at full
> >> load, and then the time extends at lower loads. However for many there
> >> is an upper limit on run time due to the parasitic losses running the
> >> inverter. So You might get an hour and a half out of a large one - but
> >> that would be the run time even with no external load at all.
> >>
> >> The solution is to move away from integrated UPS solutions where the
> >> only battery capacity available is that which is contained in the box,
> >> to one where you can add additional capacity.
> >>
> >> At it's simplest level this might be by modding a normal integrated
> >> one with more batteries, or looking at slightly more commercially
> >> focussed options. Then you can usually design not only the load you
> >> need to support, but also the run time you need.
> >>
> >> Many of the UPS vendors sites have selection tools that let you
> >> specify the load and run time, and they can offer product combinations
> >> that match.
> >>
> >> e.g. start with:
> >>
> >> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-1000VA-230V-with-Extended-Runtime-Battery-Pack/P-SRV1KIL
> >>
> >> Add another *two* of these:
> >>
> >> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-Battery-Pack-1kVA-for-Extended-Runtime-Model-36V-648VAh/P-SRV36BP-9A
> >>
> >> That gets you more than 4 hours at full load.
> >>
> >>
> >>
> >
> >
> > the cost of the UPS and extra batteries is more shocking than my
> > electricity bill!!!! :-D
> Well as you move to more commercial targeted kit, you tend to get more
> commercial prices!
> > mind you its been ages since I bought an UPS, the last one was a 750VA
> > unit for around £100.
> To be fair my example was a bit excessive - you don't need 4 hours at
> full load, and it may be that a smaller power UPS with external batts is
> available - that was what came to hand quickly. Even a cheap 450VA UPS
> hooked up to much bigger than usual SLA batts (mounted externally) might
> do the trick. (assuming they inverter does not have a temperature
> profile that limits max run time)
> > someone mentioned the other day that if you have solar PV and a power
> > wall fitted, you can have backup power if there is an external power
> > interruption and the house then becomes islanded? Is this true? If aom
> > what is the typical kVA and typical runtime of the battery if sized for
> > a 5kWp array?
> Your bog standard Solar PV will use a grid tied inverter, and so can't
> function without mains power. More sophisticated systems designed to
> time shift consumption however should be able to work without external
> power.
>
> There is no easy answer to the sizing / run time questions since they
> are interdependent. The KVA is more related to max the power of the
> inverter rather than the battery (assuming it can provide adequate
> current to meet the power demand of the inverter). The run time is
> dependant on the capacity of the batts, and the load on the inverter.

Gas backup lighting is so much easier.
Cost of light: £5-20, probably a bit more now
Installation procedure: screw in a hook
Battery life: 1 lifetime
Self discharge: none
Run time: much longer than any battery based system
Reliability: vastly better
Outputs: about 60w equivalent of light with 400w of heat. Will boil water & cook things, though not very quickly.

On 14/11/2022 22:55, Animal wrote:
> On Monday, 14 November 2022 at 14:17:44 UTC, John Rumm wrote:
>> On 13/11/2022 18:11, SH wrote:
>>> On 13/11/2022 13:36, John Rumm wrote:
>>>> On 13/11/2022 09:01, SH wrote:
>>>>> On 12/11/2022 18:47, John Rumm wrote:
>>>>>> On 12/11/2022 06:30, John J wrote:
>>>>>>> On Friday, 11 November 2022 at 14:27:13 UTC, SH wrote:
>>>>>>>> I have a downstairs lighting circuit, a 1st floor lighting circuit, a
>>>>>>>> Garage lighting circuit and a Loft lighting circuit on 4 off 6A
>>>>>>>> RCBOs.
>>>>>>>>
>>>>>>>> I also have a Smoke, Heat and CO detectors circuit on a 6A RCBO
>>>>>>>> that is
>>>>>>>> present in EVERY room (16 interlinked detectors.)
>>>>>>>>
>>>>>>>> Now I want to fit an emergency light to every room ceiling
>>>>>>>>
>>>>>>>> So thus I can wire either into the exisiting detector for that
>>>>>>>> room or
>>>>>>>> the ceiling light fitting in the room.
>>>>>>>>
>>>>>>>> Now my question for discussion: WHich is more sensible and why?
>>>>>>>>
>>>>>>>> If it makes any difference some rooms (garage / loft / downstairs
>>>>>>>> shower
>>>>>>>> room) have no windows.
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Stephen.
>>>>>>
>>>>>>> I know my way around our house in the dark.
>>>>>>
>>>>>> Not going to make a good epitaph thought is it?
>>>>>>
>>>>>> Can you do it when just woken, in smoke, when drunk etc. Your life
>>>>>> may depend on the answer.
>>>>>>
>>>>>> Now can everyone else in the house, including guests that are not so
>>>>>> familiar with the layout.
>>>>>>
>>>>>>> There's a torch kept near the consumer unit. While I don't disagree
>>>>>>> that emergency lights are handy you do sound a bit obsessive.
>>>>>>
>>>>>> Every room - perhaps, but then again we don't actually know what the
>>>>>> OPs requirements and needs are.
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> I have balance problems, very early cataracts and poor eyesight
>>>>> contrast sensitivity so a torch in a room simply does not cut it.
>>>>>
>>>>> The whole room needs to be lit during a power cut to keep myself
>>>>> safe. (The vestibular system relies on eyesight too believe it or
>>>>> not, and my eyesight sensitivity means I can't pick out objects
>>>>> visually and my cataracts means I have to have higher levels of
>>>>> illumination.
>>>>
>>>> Good points and well made :-)
>>>>
>>>>> It strikes me it would be more cost effective to put 4 bigger battery
>>>>> packs next to the home CU to do the 4 lighting circuits (ground, 1st
>>>>> floor, Loft and garage/outside lights than it is to go round every
>>>>> single light fitting poking in inverters and Li Ion batteries.....
>>>>>
>>>>> (Quick mentral calculation:
>>>>>
>>>>> ground floor is 42 off 4 watt bulbs = 168 watts max load.
>>>>>
>>>>> 1st floor is 23 off 4 watt bulbs so thats 96 watts max load.
>>>>>
>>>>> loft is two flourries currently but can change this. (I know this one
>>>>> sounds daft but it was done for the day when we have a loft
>>>>> conversion and made into a full lighting circuit)
>>>>>
>>>>> The garage/outside is 2 flourries (can change), 2.4 m LED batten and
>>>>> 14 10w or 20w LED floods and 5 5 LED bulbs.
>>>>>
>>>>> SO have wondered about using some computer UPS next to consumer unit
>>>>> but I don't think an UPS would last for 3 hours or more unless anyone
>>>>> knows different?
>>>>
>>>> In total load terms that is not a huge amount. Yes a UPS will do the
>>>> trick. What you tend to find with most "integrated" UPS devices is
>>>> they have battery capacity to provide a few mins of support at full
>>>> load, and then the time extends at lower loads. However for many there
>>>> is an upper limit on run time due to the parasitic losses running the
>>>> inverter. So You might get an hour and a half out of a large one - but
>>>> that would be the run time even with no external load at all.
>>>>
>>>> The solution is to move away from integrated UPS solutions where the
>>>> only battery capacity available is that which is contained in the box,
>>>> to one where you can add additional capacity.
>>>>
>>>> At it's simplest level this might be by modding a normal integrated
>>>> one with more batteries, or looking at slightly more commercially
>>>> focussed options. Then you can usually design not only the load you
>>>> need to support, but also the run time you need.
>>>>
>>>> Many of the UPS vendors sites have selection tools that let you
>>>> specify the load and run time, and they can offer product combinations
>>>> that match.
>>>>
>>>> e.g. start with:
>>>>
>>>> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-1000VA-230V-with-Extended-Runtime-Battery-Pack/P-SRV1KIL
>>>>
>>>> Add another *two* of these:
>>>>
>>>> https://www.apc.com/shop/uk/en/products/APC-Easy-UPS-On-Line-SRV-Battery-Pack-1kVA-for-Extended-Runtime-Model-36V-648VAh/P-SRV36BP-9A
>>>>
>>>> That gets you more than 4 hours at full load.
>>>>
>>>>
>>>>
>>>
>>>
>>> the cost of the UPS and extra batteries is more shocking than my
>>> electricity bill!!!! :-D
>> Well as you move to more commercial targeted kit, you tend to get more
>> commercial prices!
>>> mind you its been ages since I bought an UPS, the last one was a 750VA
>>> unit for around £100.
>> To be fair my example was a bit excessive - you don't need 4 hours at
>> full load, and it may be that a smaller power UPS with external batts is
>> available - that was what came to hand quickly. Even a cheap 450VA UPS
>> hooked up to much bigger than usual SLA batts (mounted externally) might
>> do the trick. (assuming they inverter does not have a temperature
>> profile that limits max run time)
>>> someone mentioned the other day that if you have solar PV and a power
>>> wall fitted, you can have backup power if there is an external power
>>> interruption and the house then becomes islanded? Is this true? If aom
>>> what is the typical kVA and typical runtime of the battery if sized for
>>> a 5kWp array?
>> Your bog standard Solar PV will use a grid tied inverter, and so can't
>> function without mains power. More sophisticated systems designed to
>> time shift consumption however should be able to work without external
>> power.
>>
>> There is no easy answer to the sizing / run time questions since they
>> are interdependent. The KVA is more related to max the power of the
>> inverter rather than the battery (assuming it can provide adequate
>> current to meet the power demand of the inverter). The run time is
>> dependant on the capacity of the batts, and the load on the inverter.
>
> Gas backup lighting is so much easier.
> Cost of light: £5-20, probably a bit more now
> Installation procedure: screw in a hook
> Battery life: 1 lifetime
> Self discharge: none
> Run time: much longer than any battery based system
> Reliability: vastly better
> Outputs: about 60w equivalent of light with 400w of heat. Will boil water & cook things, though not very quickly.

Does it come on automatically when the power fails though?

--
Colin Bignell

On 13/11/2022 10:32, ARW wrote:
> You might be better off with a generator and changeover switch - that
> will give full power (not electric showers etc) for hours.

I would be wary of relying entirely on a generator starting, if my life
depended on it, batteries are something I would have more faith in.

In article <tkvkr8$21bbf$1@dont-email.me>,
Harry Bloomfield Esq <a@harrym1byt.plus.com> wrote:
> On 13/11/2022 10:32, ARW wrote:
> > You might be better off with a generator and changeover switch - that
> > will give full power (not electric showers etc) for hours.

> I would be wary of relying entirely on a generator starting, if my life
> depended on it, batteries are something I would have more faith in.

Many systems rely on batteries at first, until the generator is running.

--
from KT24 in Surrey, England - sent from my RISC OS 4té
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

someone wrote: What about a 2nd 63A CU that is fed by a UPS with extra battery and the UPS is then connected to a standby generator.

ive seen an electrician on youtube wiring up a battery bank to a house
which is charged by solars and by off peak electricity
then powers the house at night,
and switches some circuits over to batteries in a power cut.

g