A question for the electrical wizards.

[chrispearce]

Hello.

Is it possible to power an overhead electric loco from a generator in a towed vehicle? I can't find an answer for this and am considering a layout which doesn't have any catenary but on which I would like to operate some of my overhead electric locos. I am just wondering if having a generator in a van/baggage vehicle behind the loco would, in real life, be able to provide the necessary power?

Many thanks in anticipation.

Chris.

[Bealman]

You have a model locomotive that will only operate from overhead power?

I didn't know there was such a thing! 

[railsquid]

I'm not an electrical wizard or a railway professional (so may be completely wrong), but my amateur take is that theoretically it would be possible, but generator vans presumably only provide enough power for heating/lighting/cooking etc. in passenger accommodation. For enough juice to power a locomotive you'd basically need much of the innards of a diesel-electric loco (leaving aside the question of how you get the power to the electric loco other than tying the lead to the pantograph).

In real life, if a electric locomotive needs to be moved somewhere where there are no wires, you'd just put a diesel loco in front.



Sunday WCML Drag At Blackrod 1985 by Noted HSG, on Flickr

[chrispearce]

You have a model locomotive that will only operate from overhead power?

I didn't know there was such a thing! 

No I don't have such a loco. I do have a couple of locos with dummy pantographs but don't wish to install catenary. I was merely wondering if it were possible to create a 'generator van' to 'power' them.

[chrispearce]

I'm not an electrical wizard or a railway professional (so may be completely wrong), but my amateur take is that theoretically it would be possible, but generator vans presumably only provide enough power for heating/lighting/cooking etc. in passenger accommodation. For enough juice to power a locomotive you'd basically need much of the innards of a diesel-electric loco (leaving aside the question of how you get the power to the electric loco other than tying the lead to the pantograph).

In real life, if a electric locomotive needs to be moved somewhere where there are no wires, you'd just put a diesel loco in front.

Thanks railsquid. That is helpful. Surely it must be possible to have a diesel generator that can be plugged into the loco to power it. I am sure those who preserve 3rd rail locos have done it.

[crewearpley40]

Generator vans in reality provided electric train heating, lighting. Ive only seen electric locos having failed or diversion drags over non electrified lines and pantograph down so would be unrealistic to have the pan up

[railsquid]

I'm not an electrical wizard or a railway professional (so may be completely wrong), but my amateur take is that theoretically it would be possible, but generator vans presumably only provide enough power for heating/lighting/cooking etc. in passenger accommodation. For enough juice to power a locomotive you'd basically need much of the innards of a diesel-electric loco (leaving aside the question of how you get the power to the electric loco other than tying the lead to the pantograph).

In real life, if a electric locomotive needs to be moved somewhere where there are no wires, you'd just put a diesel loco in front.

Thanks railsquid. That is helpful. Surely it must be possible to have a diesel generator that can be plugged into the loco to power it. I am sure those who preserve 3rd rail locos have done it.

The only operational 3rd rail loco I'm aware of (and again I might be wrong) is the Class 73, which has its own diesel generator on board (there's one in use on permanent way duty on the Gloucestershire/Warwickshire Railway).

[Intercity]

Are you looking for a situation where the electric is away from the wires but still at the head of the train?

Usually as stated above the diesel drag the electric and rake when there are no wires, I have seen a few times where the electric is used as the cab car/DVT surrogate, but am not sure if it took two drivers one in the electric controlling the brake and one in the diesel applying power.

A late night service to New York used to have a diesel drag in the normal way except when it got close to NY they would shut the diesel down, raise the pan on the AEM7 and control the electric from the P42 (only a few P42s had the mod to enable controlling the electric, that was an interesting ride with the diesel making no noise yet still being able to lead the train), only other time I've seen this was when 31524 rescued 87014 but the ped blew its coolant and crapped out between stafford and crewe, they raised the pan on the 87 and we limped to Crewe where a red 86 replaced everything.

A generator van or Ethel is for train heating/lights and AC, they don't provide power throughput to an engine on the train.

Ic

[chrispearce]

I may have to 'bend reality' and 'invent' one in my laboratory. Rule 1 plus wonder technology may have to be the answer.

[crewearpley40]

Your right there squiddy. The only thing i could think would be to have an on off switch on the loco roof to allow an electric loco to run pan up but that would look odd and silly without catenary

[chrispearce]

Ok. I get the impression that I could have a van behind the loco which contains a diesel generator which feeds power to the loco via a cable. The essence of the layout is a private/heritage railway where some o'head locos reside along with the more usual steam/diesel locos. I just wanted to see if it were reasonable to suggest that, although there was no catenary, the o'head locos still operated but did so by towing a generator van.

[Bealman]

You have a model locomotive that will only operate from overhead power?

I didn't know there was such a thing! 

No I don't have such a loco. I do have a couple of locos with dummy pantographs but don't wish to install catenary. I was merely wondering if it were possible to create a 'generator van' to 'power' them.

Oh, ok, sorry, I misunderstood the question. Personally I'd just use Rule 1... in fact I've done it on my layout.

I've ran an electric loco with the pantographs up, and ignored the fact there's no wires. I was the only one seeing it, and guess what, it didn't bother me at all!

[chrispearce]

You have a model locomotive that will only operate from overhead power?

I didn't know there was such a thing! 

No I don't have such a loco. I do have a couple of locos with dummy pantographs but don't wish to install catenary. I was merely wondering if it were possible to create a 'generator van' to 'power' them.

Oh, ok, sorry, I misunderstood the question. Personally I'd just use Rule 1... in fact I've done it on my layout.

I've ran an electric loco with the pantographs up, and ignored the fact there's no wires. I was the only one seeing it, and guess what, it didn't bother me at all!

Thanks. That was my genuine sentiment but I'm glad to know you've done it.

[Intercity]

You could always top and tail, electric one end-coaches-diesel on the other.

To look at that set up it would be feasible as it would be assumed the diesel provides power and the electric is just along for the ride.

[chrispearce]

You could always top and tail, electric one end-coaches-diesel on the other.

To look at that set up it would be feasible as it would be assumed the diesel provides power and the electric is just along for the ride.

A sensible idea. Thanks. BTW your 'location' is brilliant. Makes me giggle. Is Philly really a dirty place?