One batch was wired as per Thumpers, the other batch as per EMUs.Wasn't it the case that the first batch of 73s (JA) couldn't multi with the second batch (JB)? Though I think that was the situation from new rather than a result of a later modification.
Eh? What's the assumption based on, and why would it be a fudge if true?Another one that's a bit of a fudge, I'd assume that class 230s probably can't multi with class 484s despite both starting life as London Underground D78s.
Ah, that makes sense I guess. Do you know if that was planned, or if it was simply a change in standards?One batch was wired as per Thumpers, the other batch as per EMUs.
The assumption was that they may well have different specifications as they're being used by different operators with no benefit to them being able to multi, what with being on a different landmass.Eh? What's the assumption based on, and why would it be a fudge if true?
Wasn't it the case that in testing, they found out that the wires did the opposite to what they wanted to when in multiple? Or am I just creating false memories?One batch was wired as per Thumpers, the other batch as per EMUs.
Oh gotcha, I thought you were implying that a lack of 230 <> 484 compatibility would have been a disaster!It's a "fudge" on my part in terms of the topic at hand- not a fudge on the part of the railway itself!
I don't know if it counts, but the 8 x 158s brought up to ScotRail from England over 10 years ago (all now with Northern) weren't compatible with the automatic PIS when coupled to one of the core ScotRail 158s, so announcements had to be done by a guard for passengers on one of these units to hear. The ex-Wessex units still had their station departure announcements built in which would be a safety message that would be rattled out after every second station stop.Are there any trains that have been modified so much from their original form, or from the rest of their class that they don't work properly with them?
A mix of both iircAh, that makes sense I guess. Do you know if that was planned, or if it was simply a change in standards?
You know I can't recall, but that does sound familiar. I'll go and check something later which explained about the different wiring.Wasn't it the case that in testing, they found out that the wires did the opposite to what they wanted to when in multiple? Or am I just creating false memories?
I've found out what it was.Wasn't it the case that in testing, they found out that the wires did the opposite to what they wanted to when in multiple? Or am I just creating false memories?
Surely that speaks to their versatility?class 47.
BRs standard type 4, yet there is nothing standard about the class except maybe the engine.....
its 40 years ago since i trained on edls and there is many differences between ja and jbsI've found out what it was.
So the first batch was intended to be fully compatible will all post-1951 SR MUs both EMU and DEMU which were at least nominally supposed to be able to multi with each other.
During testing it was found that the EMU and DEMU fleets had been wired slightly differently and if a DEMU was to be multied with an EMU they would try and pull off in opposite directions to each other.
Through no fault of the Class 73 design it was thus found they could only work with the DEMUs, having been wired as per them.
When they went to build the second batch, now knowing of the wiring issues with the MU fleet it was decided to specifically make sure they were wired as per the EMU fleet as it was considered they would be more likely to operate with them than the DEMUs and it would be more flexible to do so.
Therefore the two batches cannot multi with each through no fault of the Class design but rather a fault of the pre-existing fleets which should've been able to work together but couldn't.
No, I don't think they can. The control wiring differs.its 40 years ago since i trained on edls and there is many differences between ja and jbs
jas have an additional demu jumper on the front but both have 27way high level and blue star low level
can a ja and jb work together ?? you got me thinking i would have said yes but some doubt now as i simply cant remember ??
That would be okay I think because that's a seperate system which uses control air for engine speed control, it was more multi-ing on electric power that wouldn't work due to the wiring differencesI've been on a train double-headed by a JA and JB, working the "Kenny Belle", on that day worked with a pair of Mark 1s. As I understand it, they could work together using the "blue star" jumpers but the JAs could not work in push-pull mode with TC stock because of the wiring issue on the 27-way connectors.
Which has come up for discussion in this thread: https://railforums.co.uk/threads/the-87-2-a-new-loco-given-same-class-number.215411/87101 was built with an experimental thryistor control system
I've read this before (on the Wikipedia page for the class 73 IIRC) but my recollection from seeing the connector pinouts (which used to be online, though I'm not sure they are now) is that the EMU and DEMU differ by a lot more than just a couple of pins. Can anyone with access to the pinout diagrams confirm?I've found out what it was.
So the first batch was intended to be fully compatible will all post-1951 SR MUs both EMU and DEMU which were at least nominally supposed to be able to multi with each other.
During testing it was found that the EMU and DEMU fleets had been wired slightly differently and if a DEMU was to be multied with an EMU they would try and pull off in opposite directions to each other.
Through no fault of the Class 73 design it was thus found they could only work with the DEMUs, having been wired as per them.
When they went to build the second batch, now knowing of the wiring issues with the MU fleet it was decided to specifically make sure they were wired as per the EMU fleet as it was considered they would be more likely to operate with them than the DEMUs and it would be more flexible to do so.
Therefore the two batches cannot multi with each through no fault of the Class design but rather a fault of the pre-existing fleets which should've been able to work together but couldn't.
They're on the RSSB website, document reference GMGN2590. But as I have a copy downloaded....I've read this before (on the Wikipedia page for the class 73 IIRC) but my recollection from seeing the connector pinouts (which used to be online, though I'm not sure they are now) is that the EMU and DEMU differ by a lot more than just a couple of pins. Can anyone with access to the pinout diagrams confirm?
Thanks -- that matches my recollection. So it doesn't look as if there's any truth in the story about them being the same except for two swapped wires.They're on the RSSB website, document reference GMGN2590. But as I have a copy downloaded....
This is what it says for Classes 205/207:
View attachment 93052
And for the EMUs:
View attachment 93053
Wires 22/23/24/27 were allocated for those purposes on Classes 421-423, but never used, obviously!
Yep! looking at it, the only thing that would work would be... the starting bell!So it doesn't look as if there's any truth in the story about them being the same except for two swapped wires.
Can a VP185 HST power car work with an MTU fitted example?
Yes of course, any engined power cars can multi with each other.Can a VP185 HST power car work with an MTU fitted example?