Ken wrote:

>You said 379s were still working to Ely. We've already established
>that I have no idea whether the panto mechanism is the same on 387s or
>any other Electrostar. And neither have you. Why can you not believe
>that the panto isolation noise is much louder on a 379 than on a 317,
>when it's coming from someone who has travelled on both types of unit
>hundreds of times?
>You, I think, described the 317 noise as a clunk. That's accurate. On
>a 379 it's a startling bang.

I have not travelled in either trains, but have a suggestion.

When the first VCB was developed (by what became Alstom),
initially at Preston, and continuing at Trafford Park, the
assembly comprised two vacuum bottles in the horizontal portion
of a "T" shape with air admitted between opposing pistons to
force the contacts together in the horizontal plane.

I signed off the production drawings. I believe this basic design
is fitted to the 317.

By Electrostar time, the design had changed, and a single vacuum
bottle could handle the duty. This now moves vertically to open
and close the contacts.

It is shown here:
<https://www.alstom.com/solutions/components/switchgear-wide-product-catalogue-answering-every-customer-need>

It may well be that the particular nature of the resonance of the
roof panels and differing shock patterns from the operation of
the two devices has unintended audible consequences .

Chris
--
Chris J Dixon Nottingham UK
chris@cdixon.me.uk @ChrisJDixon1

Plant amazing Acers.

In message <6m8t3ihp3oab8943lc29f0l9srk1rklstl@4ax.com>, at 15:06:54 on
Tue, 18 Apr 2023, Ken <ken@birchanger.com> remarked:
>On Tue, 18 Apr 2023 11:01:53 +0100, Roland Perry <roland@perry.uk>
>wrote:
>
>>In message <mnms3i1t0jqg9a6nbsooves7cgsqc2k7eb@4ax.com>, at 09:56:26 on
>>Tue, 18 Apr 2023, Ken <ken@birchanger.com> remarked:
>>>On Tue, 18 Apr 2023 06:43:36 +0100, Roland Perry <roland@perry.uk>
>>>wrote:
>>>
>>>>In message <ldvp3i1pkqnra9rhm1s37uldvue8kljm7d@4ax.com>, at 09:07:59 on
>>>>Mon, 17 Apr 2023, Ken <ken@birchanger.com> remarked:
>>>>>On Sun, 16 Apr 2023 12:22:18 +0100, Roland Perry <roland@perry.uk>
>>>>>wrote:
>>>>>
>>>>>>In message <aekn3iph59m9q6fh0qjmd3f880o1nre9qa@4ax.com>, at 11:45:48 on
>>>>>>Sun, 16 Apr 2023, Ken <ken@birchanger.com> remarked:
>>>>>>>On Sat, 15 Apr 2023 12:47:19 +0100, Roland Perry <roland@perry.uk>
>>>>>>>wrote:
>>>>>>>
>>>>>>>It was the 379s that had deafening clunks, not the 317s.
>>>>>>
>>>>>>Never noticed it on 379's (which still ply the Fen Line, if not from
>>>>>>Liverpool St). Got to love the somewhat out-of-date Gatex Branding
>>>>>>though.
>>>>>>
>>>>>You're thinking of 387s? All 379s are parked up.
>>>>
>>>>GA used to operate 379's, pre-FLIRTation.
>>>
>>>And pre-720. I know. You claimed that they were still to be found in
>>>Ely-land.
>>
>>Electrostars from Kings Cross are. Or is your theory they have a quite
>>different pantograph isolation mechanism?
>>
>You said 379s were still working to Ely.

I thought they were, but as it turns out it's visibly identical 387's.

>We've already established that I have no idea whether the panto
>mechanism is the same on 387s or any other Electrostar. And neither
>have you.

It seems to be very unlikely they'd differ much.

>Why can you not believe that the panto isolation noise is much louder
>on a 379 than on a 317, when it's coming from someone who has travelled
>on both types of unit hundreds of times?

As I've said, the noise on the 317's was deafening, if the 379's were
worse (and I've traveled on them and not noticed it) that surprises me.

>You, I think, described the 317 noise as a clunk. That's accurate. On
>a 379 it's a startling bang.
>
>>Not that any of this matters very much because 90% of my experience with
>>Electrostars in East Anglia has been pre-pandemic (and co-incidentally
>>pre-FLIRT).
>
>Well, then.

Indeed, the Kings Cross Electrostars only replaced the Networkers
quite recently, so most of my miles will have been done on the GA
Electrostars. But next time I'm out and about on an Electrostar (the
Cambridge beer festival beckons next month) I'll make a point of
travelling under the panto.
--
Roland Perry

On Tue, 18 Apr 2023 20:40:26 +0100, Chris J Dixon <chris@cdixon.me.uk>
wrote:

>Ken wrote:
>
>>You said 379s were still working to Ely. We've already established
>>that I have no idea whether the panto mechanism is the same on 387s or
>>any other Electrostar. And neither have you. Why can you not believe
>>that the panto isolation noise is much louder on a 379 than on a 317,
>>when it's coming from someone who has travelled on both types of unit
>>hundreds of times?
>>You, I think, described the 317 noise as a clunk. That's accurate. On
>>a 379 it's a startling bang.
>
>I have not travelled in either trains, but have a suggestion.
>
>When the first VCB was developed (by what became Alstom),
>initially at Preston, and continuing at Trafford Park, the
>assembly comprised two vacuum bottles in the horizontal portion
>of a "T" shape with air admitted between opposing pistons to
>force the contacts together in the horizontal plane.
>
>I signed off the production drawings. I believe this basic design
>is fitted to the 317.
>
>By Electrostar time, the design had changed, and a single vacuum
>bottle could handle the duty. This now moves vertically to open
>and close the contacts.
>
>It is shown here:
><https://www.alstom.com/solutions/components/switchgear-wide-product-catalogue-answering-every-customer-need>
>
>It may well be that the particular nature of the resonance of the
>roof panels and differing shock patterns from the operation of
>the two devices has unintended audible consequences .
>
>Chris

I don't know if this is the explanation or not, but thank you for an
interesting and informed post.

On Tue, 18 Apr 2023 06:43:36 +0100, Roland Perry <roland@perry.uk>
wrote:

>In message <ldvp3i1pkqnra9rhm1s37uldvue8kljm7d@4ax.com>, at 09:07:59 on
>Mon, 17 Apr 2023, Ken <ken@birchanger.com> remarked:

>
>Indeed so. But I don't recall that noise on the Electrostars, but
>endured it on their 317's, which used to make a patchy but routine
>appearance on the Fen Line in the evening rush hour.
>
>>>317's were ridiculously clunky.

I asked the following on ukrailforums:

"On another forum somebody suggested that class 317s made a
'deafening' clunk when entering a neutral section. I countered by
saying I'd never found it deafening and that the class 379s made a
much louder BANG that woke up and startled passengers. The other party
pointed out that he used class 387s and had never encountered such a
thing.
Is there a 387 user here who has travelled underneath the pantograph
well and can confirm or deny whether there's a bang so loud as to
temporarily stop conversation and make passengers look up in alarm, as
happens on a 379?"

I received just 3 replies, listed below. The final one seems unlikely,
but a good tip if true.

"Yes there is, and yes it has alarmed passengers on occasion.
Especially when they just recover from the first 'clunk!' when the VCB
opens, only for there to be another 'clunk!' when it closes."

"The bang certainly alarms me! I won't sit in the seats directly under
the pantograph on 387 units, nor did I on the 379s. I like a more
peaceful journey."

"The VCB can be loud, but on a warm day the air con is much better
under the pantograph well so it's often nicer to sit there. Best of
all perhaps if you're on DC!"

On Thu, 20 Apr 2023 09:32:30 +0100, Ken <ken@birchanger.com> wrote:

>On Tue, 18 Apr 2023 06:43:36 +0100, Roland Perry <roland@perry.uk>
>wrote:
>
>>In message <ldvp3i1pkqnra9rhm1s37uldvue8kljm7d@4ax.com>, at 09:07:59 on
>>Mon, 17 Apr 2023, Ken <ken@birchanger.com> remarked:
>
>>
>>Indeed so. But I don't recall that noise on the Electrostars, but
>>endured it on their 317's, which used to make a patchy but routine
>>appearance on the Fen Line in the evening rush hour.
>>
>>>>317's were ridiculously clunky.
>
>I asked the following on ukrailforums:
>
>"On another forum somebody suggested that class 317s made a
>'deafening' clunk when entering a neutral section. I countered by
>saying I'd never found it deafening and that the class 379s made a
>much louder BANG that woke up and startled passengers. The other party
>pointed out that he used class 387s and had never encountered such a
>thing.
>Is there a 387 user here who has travelled underneath the pantograph
>well and can confirm or deny whether there's a bang so loud as to
>temporarily stop conversation and make passengers look up in alarm, as
>happens on a 379?"
>
>I received just 3 replies, listed below. The final one seems unlikely,
>but a good tip if true.
>
>"Yes there is, and yes it has alarmed passengers on occasion.
>Especially when they just recover from the first 'clunk!' when the VCB
>opens, only for there to be another 'clunk!' when it closes."
>
>"The bang certainly alarms me! I won't sit in the seats directly under
>the pantograph on 387 units, nor did I on the 379s. I like a more
>peaceful journey."
>
>"The VCB can be loud, but on a warm day the air con is much better
>under the pantograph well so it's often nicer to sit there. Best of
>all perhaps if you're on DC!"
>
It definitely makes some passengers jump a bit when the Southern 387s
go through the neutral section at North Wembley and the AC/DC change
at North Pole.

Charles Ellson <charlesellson@btinternet.com> wrote:
> On Thu, 20 Apr 2023 09:32:30 +0100, Ken <ken@birchanger.com> wrote:
>
>> On Tue, 18 Apr 2023 06:43:36 +0100, Roland Perry <roland@perry.uk>
>> wrote:
>>
>>> In message <ldvp3i1pkqnra9rhm1s37uldvue8kljm7d@4ax.com>, at 09:07:59 on
>>> Mon, 17 Apr 2023, Ken <ken@birchanger.com> remarked:
>>
>>>
>>> Indeed so. But I don't recall that noise on the Electrostars, but
>>> endured it on their 317's, which used to make a patchy but routine
>>> appearance on the Fen Line in the evening rush hour.
>>>
>>>>> 317's were ridiculously clunky.
>>
>> I asked the following on ukrailforums:
>>
>> "On another forum somebody suggested that class 317s made a
>> 'deafening' clunk when entering a neutral section. I countered by
>> saying I'd never found it deafening and that the class 379s made a
>> much louder BANG that woke up and startled passengers. The other party
>> pointed out that he used class 387s and had never encountered such a
>> thing.
>> Is there a 387 user here who has travelled underneath the pantograph
>> well and can confirm or deny whether there's a bang so loud as to
>> temporarily stop conversation and make passengers look up in alarm, as
>> happens on a 379?"
>>
>> I received just 3 replies, listed below. The final one seems unlikely,
>> but a good tip if true.
>>
>> "Yes there is, and yes it has alarmed passengers on occasion.
>> Especially when they just recover from the first 'clunk!' when the VCB
>> opens, only for there to be another 'clunk!' when it closes."
>>
>> "The bang certainly alarms me! I won't sit in the seats directly under
>> the pantograph on 387 units, nor did I on the 379s. I like a more
>> peaceful journey."
>>
>> "The VCB can be loud, but on a warm day the air con is much better
>> under the pantograph well so it's often nicer to sit there. Best of
>> all perhaps if you're on DC!"
>>
> It definitely makes some passengers jump a bit when the Southern 387s
> go through the neutral section at North Wembley and the AC/DC change
> at North Pole.
>

Yes, I was wondering about that. I must try and sit near the pan next time
I take that route (not very often).

Do they still still stop near North Pole to change over?

On Wed, 26 Apr 2023 22:22:05 -0000 (UTC), Recliner
<recliner.usenet@gmail.com> wrote:

>Charles Ellson <charlesellson@btinternet.com> wrote:
>> On Thu, 20 Apr 2023 09:32:30 +0100, Ken <ken@birchanger.com> wrote:
>>
>>> On Tue, 18 Apr 2023 06:43:36 +0100, Roland Perry <roland@perry.uk>
>>> wrote:
>>>
>>>> In message <ldvp3i1pkqnra9rhm1s37uldvue8kljm7d@4ax.com>, at 09:07:59 on
>>>> Mon, 17 Apr 2023, Ken <ken@birchanger.com> remarked:
>>>
>>>>
>>>> Indeed so. But I don't recall that noise on the Electrostars, but
>>>> endured it on their 317's, which used to make a patchy but routine
>>>> appearance on the Fen Line in the evening rush hour.
>>>>
>>>>>> 317's were ridiculously clunky.
>>>
>>> I asked the following on ukrailforums:
>>>
>>> "On another forum somebody suggested that class 317s made a
>>> 'deafening' clunk when entering a neutral section. I countered by
>>> saying I'd never found it deafening and that the class 379s made a
>>> much louder BANG that woke up and startled passengers. The other party
>>> pointed out that he used class 387s and had never encountered such a
>>> thing.
>>> Is there a 387 user here who has travelled underneath the pantograph
>>> well and can confirm or deny whether there's a bang so loud as to
>>> temporarily stop conversation and make passengers look up in alarm, as
>>> happens on a 379?"
>>>
>>> I received just 3 replies, listed below. The final one seems unlikely,
>>> but a good tip if true.
>>>
>>> "Yes there is, and yes it has alarmed passengers on occasion.
>>> Especially when they just recover from the first 'clunk!' when the VCB
>>> opens, only for there to be another 'clunk!' when it closes."
>>>
>>> "The bang certainly alarms me! I won't sit in the seats directly under
>>> the pantograph on 387 units, nor did I on the 379s. I like a more
>>> peaceful journey."
>>>
>>> "The VCB can be loud, but on a warm day the air con is much better
>>> under the pantograph well so it's often nicer to sit there. Best of
>>> all perhaps if you're on DC!"
>>>
>> It definitely makes some passengers jump a bit when the Southern 387s
>> go through the neutral section at North Wembley and the AC/DC change
>> at North Pole.
>>
>
>Yes, I was wondering about that. I must try and sit near the pan next time
>I take that route (not very often).
>
>Do they still still stop near North Pole to change over?
>
Yes. They take noticeably longer (about 30sec v. 10sec ?) to change
over than a 378 which does it while coasting through.