Pendolino trailing pans

[Pete the Elaner]

I have noticed recently that Pendolinos now run with their training pantographs up. They used to use their leading pans then change over as soon as they arrived at the terminus.

 

Does anyone know when & why this practice changed?

[StaffsOatcake]

I was shouted down on another forum about this issue as I was saying that the rear pan is the pan of choice, As for a period the leading pan has been used primarily until the recent number of incidents involving wires and pans

 

The reason for the rear pan is all do with all the expensive equipment of the top of the coaches that get smashed to bits when the knitting gets torn down by a stray pan. The rear pan generally causes less damage as the knitting has less coaches to come into contact with as it whips around.

 

When they were on test over at Old Dalby it was usual for the rear pan to be raised for the majority of the runs. I only know this from personal observation when working track side

[Fat Controller]

I was shouted down on another forum about this issue as I was saying that the rear pan is the pan of choice, As for a period the leading pan has been used primarily until the recent number of incidents involving wires and pans

 

The reason for the rear pan is all do with all the expensive equipment of the top of the coaches that get smashed to bits when the knitting gets torn down by a stray pan. The rear pan generally causes less damage as the knitting has less coaches to come into contact with as it whips around.

 

When they were on test over at Old Dalby it was usual for the rear pan to be raised for the majority of the runs. I only know this from personal observation when working track side

There is also the point that, should the rear pan cause limited damage to the OCS, the front pan could then be raised and used if the contact wire above it is usable. The converse would not work. Rear pan raised is normal mode for TGVs, I believe.

[NGT6 1315]

The reason for the rear pan is all do with all the expensive equipment of the top of the coaches that get smashed to bits when the knitting gets torn down by a stray pan. The rear pan generally causes less damage as the knitting has less coaches to come into contact with as it whips around.

 

 

That's pretty much how it is on the Continent as well, and also applies to locomotives which use the rear pan unless one of a number of specified exceptions applies - such as flammable goods immediately behind the engine. Locomotives which have only one pan for the OHLE system in question - such as several variants of the Siemens ES 64 F4 type, or indeed Bombardier's class 186, both of which have only one pan for Germany - obviously have to use that pantograph, regardless of which cab is in front and which kinds of goods are behind the engine. Apart from such issues, it does, strictly speaking, not matter whether the front or rear pan is being used, as long as it is compatible with the current OHLE.

[Guest jim s-w]

Hiya

 

I was of the understanding that the shape of a pendo's front causes too much upward air pressure on the leading pan resulting in the uplift being too strong and damaging the OLE. Thus they initially ran with the front pans up but when the problem came to light a switch was made to the rear pan. I have an email somewhere from a OLE engineer that has the figures, I will see if i can dig it out.

 

HTH

 

Jim

[StaffsOatcake]

Hiya

 

I was of the understanding that the shape of a pendo's front causes too much upward air pressure on the leading pan resulting in the uplift being too strong and damaging the OLE. Thus they initially ran with the front pans up but when the problem came to light a switch was made to the rear pan. I have an email somewhere from a OLE engineer that has the figures, I will see if i can dig it out.

 

HTH

 

Jim

 

I read this thread with great interest and listen with glee as many of you are raising the same reasons that I raised only to be decried by other enthusiasts as been 'nonsense'

[StaffsOatcake]

The order was issued by Network rail on December the 21st following a number of incidents at the south end of the WCML.

 

It should save both Network rail and Vermin a fortune

[The Stationmaster]

I read this thread with great interest and listen with glee as many of you are raising the same reasons that I raised only to be decried by other enthusiasts as been 'nonsense'

 

I don't know about the Pendolinos but pan uplift and aerodynamics can cause serious problems with ohle. If the up force is too strong it sets up bounce and whip, and all sorts of other unwanted behaviour, in the contact wire. So I wouldn't be surprised to hear that it can bring it down in some circumstances - especially if it is BR MkIII ohle (which is far less 'rigid' than the earlier BR 25kv designs).

[Guest D.J.K.]

Hi all,

 

Firstly Pendo pans aren't unidirectional.. If for any reason only one pan is available the set can run all day like that...

 

When the Pendos were being introduced, it was always the intention to run with the rear pan up....

 

IIRC during the commissioning process there were issues of some sort that required a change to front pan operation. Not sure, but it may have been related to electrical interference at certain locations across the network...

 

At about the same time, the secondary aerofoils near the pantograph knuckles were removed....

 

Recently an instruction was issued stating that any outstanding issues had been resolved and rear pan operation could resume.....

 

As for the "uplift" issues. Yes, there were quite a few Pan/OHL problems last year. It'd be interesting to know if those incidents were actually part of the reason for returning to rear pan operation......

[StaffsOatcake]

It was always my understanding that the Biggest knuckle should always point forward for the best contact with the knitting. Which is the way they are positioned on the rear of the pende's so it would appear that they were built the right way, just that it was thought better to run them with the leading pan up. Typical.

[298]

And I thought one was for 25kV and the other for 6.25kv....