All the corridors and some of the rooms in my office building have
emergency lights with what I think is the usual switch arrangement: a
two-hole grid plate with a normal switch for the main lights beside a
key-operated switch for the emergency light.

I recently saw someone going through the building testing the lights
and I noticed that each keyed switch cuts the power to the emergency
lights (so the little green charging indicator goes off and the
emergency light comes on) but also cuts the power to the main light (I
watched and the tester was not flipping the "normal" switch).

So I'm just curious why the test switches cut off the main lights ---
is it just to make it more immediately obvious that the emergency ones
are working?

On 23/03/2023 12:34, Adam Funk wrote:
> All the corridors and some of the rooms in my office building have
> emergency lights with what I think is the usual switch arrangement: a
> two-hole grid plate with a normal switch for the main lights beside a
> key-operated switch for the emergency light.
>
> I recently saw someone going through the building testing the lights
> and I noticed that each keyed switch cuts the power to the emergency
> lights (so the little green charging indicator goes off and the
> emergency light comes on) but also cuts the power to the main light (I
> watched and the tester was not flipping the "normal" switch).
>
> So I'm just curious why the test switches cut off the main lights ---
> is it just to make it more immediately obvious that the emergency ones
> are working?

Probably because it is the failure of the main lighting circuit that
triggers the emergency lights to come on.

--
Colin Bignell

On 23/03/2023 12:34, Adam Funk wrote:
> All the corridors and some of the rooms in my office building have
> emergency lights with what I think is the usual switch arrangement: a
> two-hole grid plate with a normal switch for the main lights beside a
> key-operated switch for the emergency light.
>
> I recently saw someone going through the building testing the lights
> and I noticed that each keyed switch cuts the power to the emergency
> lights (so the little green charging indicator goes off and the
> emergency light comes on) but also cuts the power to the main light (I
> watched and the tester was not flipping the "normal" switch).
>
> So I'm just curious why the test switches cut off the main lights ---
> is it just to make it more immediately obvious that the emergency ones
> are working?

Emergency lights come in two forms - non maintained, and maintained. The
difference is that the maintained ones can be switched on with a switch,
or by disconnecting the power. The non maintained ones don't have the
switch option, so the only way to turn them on manually is to cut the
power. The cheapest and most commonly used are the non maintained ones.

So the key switch just needs to simulate failure of power to the
circuit. You also don't need extra wiring for a separate switch to the
lamp. That will test the lights - including their batteries and
inverters etc. The side effect will be to cut power to the normal
switched lights as well.

--
Cheers,

John.

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

On 23/03/2023 15:13, John Rumm wrote:

> Emergency lights come in two forms - non maintained, and maintained. The
> difference is that the maintained ones can be switched on with a switch,
> or by disconnecting the power. The non maintained ones don't have the
> switch option, so the only way to turn them on manually is to cut the
> power. The cheapest and most commonly used are the non maintained ones.

And in many (not all) units on sale the only difference is the provision
for a link on a connector.
Many unit sold as non maintained can be wired in three ways.
i) Off whilst mains is being supplied and on via a battery when the
mains fails.
ii) Permanently on whilst mains is being supplied and on via the battery
when the mains fails.
iii) On/off via wall switch whilst mains is being supplied and on via
the battery when the mains fails.

I have two units purchased as non-maintained. One that has a three
terminal connector for the permanent mains and cannot easily be
converted without possibly getting to the circuit board. The other has
an additional terminal for switched live which can either be linked
internally to the permanent live or alternatively linked via a switch.
--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 23/03/2023 12:34, Adam Funk wrote:
> All the corridors and some of the rooms in my office building have
> emergency lights with what I think is the usual switch arrangement: a
> two-hole grid plate with a normal switch for the main lights beside a
> key-operated switch for the emergency light.
>
> I recently saw someone going through the building testing the lights
> and I noticed that each keyed switch cuts the power to the emergency
> lights (so the little green charging indicator goes off and the
> emergency light comes on) but also cuts the power to the main light (I
> watched and the tester was not flipping the "normal" switch).
>
> So I'm just curious why the test switches cut off the main lights ---
> is it just to make it more immediately obvious that the emergency ones
> are working?

I wonder what testing regime they had? When one of my emergency lights
came to the end of it life a quick couple of minutes check wouldn't have
identified it. With mains removed the light came on but for only around
10/15 minutes and not the 3 hours when new.
The old unit had a fluorescent tube and I elected to replace it with a
LED version rather than just replacing the battery.

Note: the availability of fluorescent light products is likely to be
somewhat limited now, or a bit later this year.

https://www.watt24.com/en/guide/fluorescent-tubes-ban-2023-all-you-need-to-know/

or

https://tinyurl.com/2p96jrsd

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

On 2023-03-23, John Rumm wrote:

> On 23/03/2023 12:34, Adam Funk wrote:
>> All the corridors and some of the rooms in my office building have
>> emergency lights with what I think is the usual switch arrangement: a
>> two-hole grid plate with a normal switch for the main lights beside a
>> key-operated switch for the emergency light.
>>
>> I recently saw someone going through the building testing the lights
>> and I noticed that each keyed switch cuts the power to the emergency
>> lights (so the little green charging indicator goes off and the
>> emergency light comes on) but also cuts the power to the main light (I
>> watched and the tester was not flipping the "normal" switch).
>>
>> So I'm just curious why the test switches cut off the main lights ---
>> is it just to make it more immediately obvious that the emergency ones
>> are working?
>
> Emergency lights come in two forms - non maintained, and maintained. The
> difference is that the maintained ones can be switched on with a switch,
> or by disconnecting the power. The non maintained ones don't have the
> switch option, so the only way to turn them on manually is to cut the
> power. The cheapest and most commonly used are the non maintained ones.
>
> So the key switch just needs to simulate failure of power to the
> circuit. You also don't need extra wiring for a separate switch to the
> lamp. That will test the lights - including their batteries and
> inverters etc. The side effect will be to cut power to the normal
> switched lights as well.

That makes sense, thanks.

On 2023-03-24, alan_m wrote:

> On 23/03/2023 12:34, Adam Funk wrote:
>> All the corridors and some of the rooms in my office building have
>> emergency lights with what I think is the usual switch arrangement: a
>> two-hole grid plate with a normal switch for the main lights beside a
>> key-operated switch for the emergency light.
>>
>> I recently saw someone going through the building testing the lights
>> and I noticed that each keyed switch cuts the power to the emergency
>> lights (so the little green charging indicator goes off and the
>> emergency light comes on) but also cuts the power to the main light (I
>> watched and the tester was not flipping the "normal" switch).
>>
>> So I'm just curious why the test switches cut off the main lights ---
>> is it just to make it more immediately obvious that the emergency ones
>> are working?
>
>
> I wonder what testing regime they had? When one of my emergency lights
> came to the end of it life a quick couple of minutes check wouldn't have
> identified it. With mains removed the light came on but for only around
> 10/15 minutes and not the 3 hours when new.

The testing I saw very quick, probably less than a minute for each
keyed switch. Maybe they do longer tests then the building is mostly
unoccupied, but I don't know.

> The old unit had a fluorescent tube and I elected to replace it with a
> LED version rather than just replacing the battery.
>
>
> Note: the availability of fluorescent light products is likely to be
> somewhat limited now, or a bit later this year.
>
> https://www.watt24.com/en/guide/fluorescent-tubes-ban-2023-all-you-need-to-know/
>
> or
>
> https://tinyurl.com/2p96jrsd

On 24/03/2023 09:33, alan_m wrote:
> On 23/03/2023 12:34, Adam Funk wrote:
>> All the corridors and some of the rooms in my office building have
>> emergency lights with what I think is the usual switch arrangement: a
>> two-hole grid plate with a normal switch for the main lights beside a
>> key-operated switch for the emergency light.
>>
>> I recently saw someone going through the building testing the lights
>> and I noticed that each keyed switch cuts the power to the emergency
>> lights (so the little green charging indicator goes off and the
>> emergency light comes on) but also cuts the power to the main light (I
>> watched and the tester was not flipping the "normal" switch).
>>
>> So I'm just curious why the test switches cut off the main lights ---
>> is it just to make it more immediately obvious that the emergency ones
>> are working?
>
>
> I wonder what testing regime they had?

The regime in my factories was to check that the emergency lights came
on when the mains failed as part of the factory's monthly planned
maintenance, with a four hour test as part of a less frequent planned
maintenance. I think that was the annual one, when lamps were being
cleaned or replaced and production was stopped for other annual maintenance.

When one of my emergency lights
> came to the end of it life a quick couple of minutes check wouldn't have
> identified it. With mains removed the light came on but for only around
> 10/15 minutes and not the 3 hours when new.
> The old unit had a fluorescent tube and I elected to replace it with a
> LED version rather than just replacing the battery.
>
>
> Note: the availability of fluorescent light products is likely to be
> somewhat limited now, or a bit later this year.
>
> https://www.watt24.com/en/guide/fluorescent-tubes-ban-2023-all-you-need-to-know/
>
> or
>
> https://tinyurl.com/2p96jrsd
>

--
Colin Bignell

In message <k8593dFhu6tU1@mid.individual.net>, alan_m
<junk@admac.myzen.co.uk> writes
snip
>Note: the availability of fluorescent light products is likely to be
>somewhat limited now, or a bit later this year.

I have a flock of part used 5' and some 6' tubes if anyone has a need:-)
>
>https://www.watt24.com/en/guide/fluorescent-tubes-ban-2023-all-you-need-
>to-know/
>
>or
>
>https://tinyurl.com/2p96jrsd
>

--
Tim Lamb

On Friday, 24 March 2023 at 09:33:37 UTC, alan_m wrote:
> On 23/03/2023 12:34, Adam Funk wrote:
> > All the corridors and some of the rooms in my office building have
> > emergency lights with what I think is the usual switch arrangement: a
> > two-hole grid plate with a normal switch for the main lights beside a
> > key-operated switch for the emergency light.
> >
> > I recently saw someone going through the building testing the lights
> > and I noticed that each keyed switch cuts the power to the emergency
> > lights (so the little green charging indicator goes off and the
> > emergency light comes on) but also cuts the power to the main light (I
> > watched and the tester was not flipping the "normal" switch).
> >
> > So I'm just curious why the test switches cut off the main lights ---
> > is it just to make it more immediately obvious that the emergency ones
> > are working?
> I wonder what testing regime they had? When one of my emergency lights
> came to the end of it life a quick couple of minutes check wouldn't have
> identified it. With mains removed the light came on but for only around
> 10/15 minutes and not the 3 hours when new.
> The old unit had a fluorescent tube and I elected to replace it with a
> LED version rather than just replacing the battery.
>
>
> Note: the availability of fluorescent light products is likely to be
> somewhat limited now, or a bit later this year.
>
> https://www.watt24.com/en/guide/fluorescent-tubes-ban-2023-all-you-need-to-know/
>
> or
>
> https://tinyurl.com/2p96jrsd

Does thst mean no more halogen headlamp bulbs? Can LEDs be retrofitted into halogen designs & give suitable beam pattern?

On Fri, 24 Mar 2023 09:57:09 -0700 (PDT)
Animal <tabbypurr@gmail.com> wrote:

> On Friday, 24 March 2023 at 09:33:37 UTC, alan_m wrote:
> > https://tinyurl.com/2p96jrsd
>
> Does thst mean no more halogen headlamp bulbs? Can LEDs be
> retrofitted into halogen designs & give suitable beam pattern?

Why would legislation on mercury vapour lamps affect halogen lamps?

On Friday, 24 March 2023 at 20:02:38 UTC, Rob Morley wrote:
> On Fri, 24 Mar 2023 09:57:09 -0700 (PDT)
> Animal <tabb...@gmail.com> wrote:
>
> > On Friday, 24 March 2023 at 09:33:37 UTC, alan_m wrote:
> > > https://tinyurl.com/2p96jrsd
> >
> > Does thst mean no more halogen headlamp bulbs? Can LEDs be
> > retrofitted into halogen designs & give suitable beam pattern?
> Why would legislation on mercury vapour lamps affect halogen lamps?

I assume it covers both for the same reason, poor energy efficiency. Halogens aren't significantly toxic afaik.