Why are Class 90s used in pairs?

[Class15]

Why are Class 90s used in pairs on Intermodals? Can one not manage the load?

 

[Ayrshire Roy]

One could handle the load but two give better acceleration and more importantly can run at a higher speed up Shap and Beattock.

 

[Class15]

One could handle the load but two give better acceleration and more importantly can run at a higher speed up Shap and Beattock.

Thanks! So 1 could be used if necessary?

 

[Ayrshire Roy]

Thanks! So 1 could be used if necessary?

I think so but they run the risk of holding up the pendolinos.

 

[Andy Pacer]

I seem to recall reading somewhere a while ago they were also used in pairs in case one failed!

 

[zwk500]

Another reason is it gives better brake force.

 

[Snow1964]

Why are Class 90s used in pairs on Intermodals? Can one not manage the load?

The can usually manage the load, but can’t be guaranteed to accelerate quickly in bad weather when rails are wet or icy.

If they can’t maintain schedule then will delay passenger trains behind them

Class 90s are mixed traffic locos, not heavy haul freight locos

 

[Iskra]

I seem to recall reading somewhere a while ago they were also used in pairs in case one failed!

Wasn’t that a reference to the old 86’s?

(What’s happened to those loco’s now?)

 

[zwk500]

Wasn’t that a reference to the old 86’s?

(What’s happened to those loco’s now?)

Some were exported to Bulgaria, a couple have been preserved, but most have been scrapped as they were replaced by the Class 90s to give Freightliner a common fleet.

 

[DarloRich]

Wasn’t that a reference to the old 86’s?

(What’s happened to those loco’s now?)

Some were exported to Bulgaria, a couple have been preserved, but most have been scrapped as they were replaced by the Class 90s to give Freightliner a common fleet.

There was a line of them on crewe basford hall last time i passed

 

[306024]

I seem to recall reading somewhere a while ago they were also used in pairs in case one failed!

Well I’d suggest stop reading where that came from

Someone more knowledgable will confirm or correct me but when the class 90s left GA, weren’t they down rated for freightliner, so that effectively it was like having one and a half class 90s on the front.

Not unknown for a single class 90 to slip to a stand climbing Brentwood bank, never mind Shap or Beattock.

 

[Andy Pacer]

Wasn’t that a reference to the old 86’s?

(What’s happened to those loco’s now?)

Aah yes could be now I think about it. Thanks!

 

[Ken H]

Cos heavy haul needs Co-Co locos with serious grunt. Not hand me down passenger locos.

 

[Iskra]

Cos heavy haul needs Co-Co locos with serious grunt. Not hand me down passenger locos.

These services have operated with hand me down passenger loco’s quite successfully for decades…

 

[D365]

Some were exported to Bulgaria, a couple have been preserved, but most have been scrapped as they were replaced by the Class 90s to give Freightliner a common fleet.

Has it been confirmed that Freightliner scrapped their Class 86s? I was under the impression that they are to remain in situ (Crewe) for the foreseeable.

Someone more knowledgable will confirm or correct me but when the class 90s left GA, weren’t they down rated for freightliner, so that effectively it was like having one and a half class 90s on the front.

Sort of - one motor per loco is isolated when operating in a pair.

 

[306024]

Sort of - one motor per loco is isolated when operating in a pair.

Thanks, knew there had been a trial some time ago but didn’t know what became of it.

 

[zwk500]

Has it been confirmed that Freightliner scrapped their Class 86s? I was under the impression that they are to remain in situ (Crewe) for the foreseeable.

I dont have confirmation no, and I'm not really up to date so they may well be in olong term storage rather than scrapped.

 

[Ken H]

Has it been confirmed that Freightliner scrapped their Class 86s? I was under the impression that they are to remain in situ (Crewe) for the foreseeable.

Sort of - one motor per loco is isolated when operating in a pair.

I thought rotating DC electric motors when isolated damaged them. Glazing of the commutator. If I remember correctly, thats why the HST power cars were actually giving power when operating as surrogate DVT for the early running with Cl 91

 

[LNW-GW Joint]

Cos heavy haul needs Co-Co locos with serious grunt. Not hand me down passenger locos.

On the Brenner line last week (Italy-Austria-Germany), most of the many heavy freights were in the hands of 2xclass 1216 Siemens Taurus Bo-Bos.
Trains were mostly intermodal, or car-carriers, or TOFC (road trailers on flat cars).
2xTaurus (dual voltage) seems to be the standard equipment on trans-alpine routes.
2xclass 90s come close to that model, though they are nothing like as powerful as the Taurus class.

 

[hwl]

Sort of - one motor per loco is isolated when operating in a pair.

Not quite, that was the old arrangement. The new arrangement is software based current limiting to avoid drawing more than the permitted max current. So 4 motors are fully available most of the time with slightly reduced max power per motor at some intermediate speeds, which is much better than isolating 1 motor (the simple quick and easy solution).

One could handle the load but two give better acceleration and more importantly can run at a higher speed up Shap and Beattock.

Exactly, the max permitted train length and weight would have top be reduced for just 1 loco in order to keep to time/path.

Thanks! So 1 could be used if necessary?

But resulting in fewer wagons per train inorder to keep to time...

Thanks, knew there had been a trial some time ago but didn’t know what became of it.

That was the old operating arrangement not the trial /new operating arrangement.

 

[ac6000cw]

On the Brenner line last week (Italy-Austria-Germany), most of the many heavy freights were in the hands of 2xclass 1216 Siemens Taurus Bo-Bos.
Trains were mostly intermodal, or car-carriers, or TOFC (road trailers on flat cars).
2xTaurus (dual voltage) seems to be the standard equipment on trans-alpine routes.
2xclass 90s come close to that model, though they are nothing like as powerful as the Taurus class.

Yes - use one modern high-power Bo-Bo for trains on relatively flat/modestly graded routes, and add another one when you get into the more serious gradients in the mountains. I think OBB only has 4-axle electric locos. Last time I was in Switzerland, pairs of modern Bo-Bo's were pretty common on freights in the mountains, particularly on 'run through' trains to/from other countries.

Is Stadler the only major European supplier who offers a high-power Co-Co electric? (albeit in the form of a diesel/OHLE bimode, where part of the reason for having six axles is to carry the extra weight of the diesel engine, cooling system and fuel)

 

[156444]

I dont have confirmation no, and I'm not really up to date so they may well be in olong term storage rather than scrapped.

The Freightliner 86s are all in Basford Hall yard except 86622, which is at Crewe Heritage Centre. Unless they've been moved recently, there's a line of 8 near the road bridge and a line of 7 closer to the depot.

 

[ac6000cw]

What was reported on this forum at the time the 86's were taken out service, was that FL was storing them in case of possible further use or rebuilding.

Given that they are over 55 years old, personally it feels unlikely anyone would spend a lot of money on a serious rebuild. Pure speculation, but I think a bit more likely is that FL might eventually follow GBRf's lead and buy/lease some class 99 Co-Co bi-modes or an OHLE+battery version of it (and use one in place of a pair of 90's).

 

[delticdave]

Yes - use one modern high-power Bo-Bo for trains on relatively flat/modestly graded routes, and add another one when you get into the more serious gradients in the mountains. I think OBB only has 4-axle electric locos. Last time I was in Switzerland, pairs of modern Bo-Bo's were pretty common on freights in the mountains, particularly on 'run through' trains to/from other countries.

Is Stadler the only major European supplier who offers a high-power Co-Co electric? (albeit in the form of a diesel/OHLE bimode, where part of the reason for having six axles is to carry the extra weight of the diesel engine, cooling system and fuel)

Siemens / Krauss-Maffei built a batch of 13 6-axle E-Loks for freight service between Germany & Denmark / Sweden. They are bi-voltage loks, 15 & 25 kV, numbered EG 3101 to 3113. Allowed to run at 140 k/mh max & rated at 6500 kW, (to cope with the gradients in/on the Great Belt's tunnels & bridges).

 

[ac6000cw]

Siemens / Krauss-Maffei built a batch of 13 6-axle E-Loks for freight service between Germany & Denmark / Sweden. They are bi-voltage loks, 15 & 25 kV, numbered EG 3101 to 3113. Allowed to run at 140 k/mh max & rated at 6500 kW, (to cope with the gradients in/on the Great Belt's tunnels & bridges).

Built 20+ years ago though.

There are also the 34 IORE Co-Co's from Adtranz/Bombardier (built 2000 - 2014) used on the iron ore trains in northern Sweden & Norway.

But compared to the thousands of EuroSprinter/Vectron/TRAXX/Prima series Bo-Bo's built over the last 25 years or so, the Co-Co's built over the same period are a drop in ocean really.

 

[D365]

Not quite, that was the old arrangement. The new arrangement is software based current limiting to avoid drawing more than the permitted max current. So 4 motors are fully available most of the time with slightly reduced max power per motor at some intermediate speeds, which is much better than isolating 1 motor (the simple quick and easy solution).

That was the old operating arrangement not the trial /new operating arrangement.

Ah, so they did find a way to modify the microprocessor code...

 

[43096]

Is Stadler the only major European supplier who offers a high-power Co-Co electric? (albeit in the form of a diesel/OHLE bimode, where part of the reason for having six axles is to carry the extra weight of the diesel engine, cooling system and fuel)

Stadler offer the Euro6000, which is a straight electric 6MW electric loco Co-Co. There’s also the Euro9000 which is a 9MW Co-Co, but which also has two smaller diesels for last mile work (and power boost under DC catenary).

 

[ac6000cw]

Stadler offer the Euro6000, which is a straight electric 6MW electric loco Co-Co.

So basically a Euro Dual without the diesel part.

There’s also the Euro9000 which is a 9MW Co-Co, but which also has two smaller diesels for last mile work (and power boost under DC catenary).

That looks quite a beast - for the European Loc Pool version: up to 9MW (about 12,000hp) on electric, multi-system 25 kV AC / 15 kV AC / 3 kV DC / 1.5 kV DC, and 1900 kW (about 2500hp) on diesel.

 

[spookywestie]

Ah, so they did find a way to modify the microprocessor code...

Not quite, that was the old arrangement. The new arrangement is software based current limiting to avoid drawing more than the permitted max current. So 4 motors are fully available most of the time with slightly reduced max power per motor at some intermediate speeds, which is much better than isolating 1 motor (the simple quick and easy solution).

The mod is not software based, it is all physical hardware added on. In each cab there are some new resistors connected to the encoder board, connected/disconnected via a new relay under the power controller. To ensure it's only active when in multi there is an existing relay utilised, TNR I think. TNR is only energised when configured with another vehicle. The new relays in the cabs are fed 110v dc via that existing relay and an isolation switch.
The net result is a lower capped voltage output from the cab controller to the electronics rack.

I helped fit the mods, but it was over 2 years since the last one so my memory is a bit fuzzy.

 

[Efini92]

Another reason is it gives better brake force.

Would an extra loco give much extra brake force?