Class 68 and 88 working in multiple

[jonty14]

Good evening.
Can a class 68 work in multiple with an 88 in electric mode? Also how many class 66 locos can work powered in multiple together? Just wondering.

 

[BMIFlyer]

Yes the 68 and 88 can work in tandem / multiple.

 

[jonty14]

Thank you BMIFlyer

 

[Highlandspring]

Though “tandem working” and “multiple working” are not the same thing......... In any case 68s and 88s can work in multiple.

 

[gingertom]

Yes the 68 and 88 can work in tandem / multiple.

can they do top and tail, assuming appropriate wiring through the coaches? 100mph bi-mode HST.

 

[Roast Veg]

The class 68 does not (presumably) have the required controls to change the power mode of the 88.

The performance on diesel is such that you may as well be running the 68 on its own, and the performance on electric is such that you may as well be running the 88 on its own.

Can the class 88 change power mod at speed?

 

[James James]

The class 68 does not (presumably) have the required controls to change the power mode of the 88.

The performance on diesel is such that you may as well be running the 68 on its own, and the performance on electric is such that you may as well be running the 88 on its own.

How so? 3kW (class 68) vs 1/4kW (88 diesel/electric)? On diesel that's 25% more power, on electric 75% more, could be useful.

 

[Rail Blues]

How so? 3kW (class 68) vs 1/4kW (88 diesel/electric)? On diesel that's 25% more power, on electric 75% more, could be useful.

Useful for what and to whom?

 

[James James]

Useful for what and to whom?

That's for the user to decide.

 

[Rail Blues]

That's for the user to decide.

That's rather my point, who do you imagine the user would be?

If you chuck enough money and time at anything you could make it work, however whether something is sensible, practical or serves any earthly purpose whatsoever is a different question altogether. To which the answer is no, no and thrice no.

 

[James James]

That's rather my point, who do you imagine the user would be?

If you chuck enough money and time at anything you could make it work, however whether something is sensible, practical or serves any earthly purpose whatsoever is a different question altogether. To which the answer is no, no and thrice no.

The original poster claimed that the performance of the two locos was such that running both at the same time doesn't supply any more useable power. I was merely pointing out that, in fact, running both locos does add more useable power - 25 or 75% depending on configuration in fact. Whether or not that's practically useful for anyone is beyond the scope of my answer, I was merely correcting a factually incorrect statement.

 

[Rob F]

The original poster claimed that the performance of the two locos was such that running both at the same time doesn't supply any more useable power. I was merely pointing out that, in fact, running both locos does add more useable power - 25 or 75% depending on configuration in fact. Whether or not that's practically useful for anyone is beyond the scope of my answer, I was merely correcting a factually incorrect statement.

Has anyone confirmed that a 68 can work in multiple with an 88 when the 88 is in electric mode? I know they can when the 88 is on diesel.

 

[Rail Blues]

The original poster claimed that the performance of the two locos was such that running both at the same time doesn't supply any more useable power. I was merely pointing out that, in fact, running both locos does add more useable power - 25 or 75% depending on configuration in fact. Whether or not that's practically useful for anyone is beyond the scope of my answer, I was merely correcting a factually incorrect statement.

But to be useful it has to have a purpose...

 

[Highlandspring]

Has anyone confirmed that a 68 can work in multiple with an 88 when the 88 is in electric mode? I know they can when the 88 is on diesel.

I don’t have a publicly visible document to cite here but they can indeed work in multiple with the 88 in electric mode.

 

[Rob F]

I don’t have a publicly visible document to cite here but they can indeed work in multiple with the 88 in electric mode.

Thanks

 

[James James]

But to be useful it has to have a purpose...

Certainly.

 

[Roast Veg]

The original poster claimed that the performance of the two locos was such that running both at the same time doesn't supply any more useable power. I was merely pointing out that, in fact, running both locos does add more useable power - 25 or 75% depending on configuration in fact. Whether or not that's practically useful for anyone is beyond the scope of my answer, I was merely correcting a factually incorrect statement.

My phrasing was "you may as well" - in that I do not believe there to be an operational use for such an arrangement. Of course they supply a non zero amount of additional tractive effort, that much is obvious and wasn't what I wanted to infer.

 

[DelW]

Good evening.
Can a class 68 work in multiple with an 88 in electric mode? Also how many class 66 locos can work powered in multiple together? Just wondering.

No-one has answered the second question, and I don't know the answer either. But the 66s and their control systems were based on the SD40-2, and in the US those were regularly used with three or four locos working in multiple. Less often it was possible to see up to about eight locos at the head of a train, but not all of those would necessarily be working, some might be being relocated dead in tow.

 

[Highlandspring]

I didn’t notice the second question when posting my first answer... but it just so happens that I have a copy of the EMD JT42CWR (aka class 66) operating manual in front of me which covers the original EWS 66001 to 66250 batch. In the ‘General Description’ section it says -

While each JT42CWR locomotive is an independent power source, a number of similar units (2, maximum 3) may be combined in a multiple-unit to increase load capacity

I also have a manual for the EMD JT26CW-SS (aka class 59) which dates from 1995 and covers the former National Power locos 59202 to 59206. It contains a very similar paragraph but curiously it doesn’t mention a maximum number.

 

[Iskra]

But to be useful it has to have a purpose...

Dipping into the realms of fantasy...

...could it not theoretically be useful to have an 88 and a 68 at the head of the train if one could control the other, to create a better go-anywhere bi-mode arrangement without having to swap loco's at any point in a journey. It's niche. But it could offer an advantage.

However, I'm guessing track access charges would make dragging an unnecessary loco around uneconomic and you probably can't control one from the other so the point is moot.

 

[jonty14]

Thanks for the replies everyone. Most appreciated.

 

[DelW]

I didn’t notice the second question when posting my first answer... but it just so happens that I have a copy of the EMD JT42CWR (aka class 66) operating manual in front of me which covers the original EWS 66001 to 66250 batch. In the ‘General Description’ section it says -


I also have a manual for the EMD JT26CW-SS (aka class 59) which dates from 1995 and covers the former National Power locos 59202 to 59206. It contains a very similar paragraph but curiously it doesn’t mention a maximum number.

Thinking about it, I was wrong, it was the class 59 that was based on the SD40-2, not the class 66. I don't think the class 66 had a direct freight equivalent in the US, although there were 4-axle passenger locos that used the 12-710 engine.

 

[Highlandspring]

Good evening.
Can a class 68 work in multiple with an 88 in electric mode? Also how many class 66 locos can work powered in multiple together? Just wondering.

Sorry to drag this thread up again from the depths of the forum but I thought it was worth recording that 68004 and 88007 worked in multi this morning on 4Z43 0345 Carlisle NY to Mossend PD Stirling, the 88 in electric mode with pan up.

 

[themiller]

From a Facebook reply to a similar question about a year ago, class 68 & class 88 can work in multiple but the 68 cannot control the 88's pantograph. This means that if the 88 leads, all combinations of power are available but if the 68 leads, the 88 needs manual intervention to change mode.

 

[GrimShady]

Has anyone confirmed that a 68 can work in multiple with an 88 when the 88 is in electric mode? I know they can when the 88 is on diesel.

How would this work, obviously the 88 at any notch setting is far more powerful than the 68?

 

[Fincra5]

How would this work, obviously the 88 at any notch setting is far more powerful than the 68?

Surely like a 170 coupled with a 153 or similar.

 

[swaldman]

I think what the OP was getting at is that, based on the replies, if you have a 68 and 88 at opposite ends of a train, you have a train that you can drive at both ends that has a 100mph limit and at least as much power as an HST available on either diesel or electric. Albeit with some additional faff on electric if the 88 is at the back.

Whether there's any economic sense in actually doing that, and effectively lugging a dead loco around all the time (OK, technically the 88 could help a bit on diesel), I don't know!

 

[driver_m]

Would have thought the 88 can't be used in AC mode if it's not the lead Loco as you won't have a linelight to show a supply, the ability to drop the pan for emergency or for coasting purposes, and a way of monitoring for problems with the equipment. (Showing my age here but tapchanger AC's could be overloaded from a DVT without seeing the ammeter)

I could have sworn I saw a pair the other day on a nuke heading out of Crewe and the lead one having a pan. Obvious answer to all this would be a DRS driver being able to answer these questions.