loss of power to class 47 traction motors
 

Does any techno-wiz know why a class 47 should start and not send power to the traction motors? Is it a common problem for any diesel or peculiar to Brush locos?

My best guess would be a generator fault.
If no power is reaching the traction motors then the loco is going nowhere.

A while ago in Heritage railway magazine there was a warning of fire to 47's.
This is due to parts becoming worn.
I think it is something to do with generators.
Maybe a wire burnt out.

There is talk about a diode being the problem but that wont carry the kind of voltage going from the generator to the traction motors! But thks for your input.

If the generator is an alternator (AC) then you need something to rectify the AC to DC for the traction motors and diodes could be used for that.

According to my reference most 47s were fitted with generators, not alternators depending on the loco number.

Is yours 47793 ? Should have had the Brush TG160-60 or TG172-50 generator.

http://myweb.tiscali.co.uk/roysrailp...etails/47.html





Philip.

Thks Philip. Correct on the loco no. too.

http://mikepiddington.fotopic.net/c1754241.html

Sorry to say its not my loco!!!

Control air Isolating cock shut.
Stops the reversers working

what kind of voltage is going through these electronic control boards??
I know a good source of components but am worried about the loading on board the 47!

When you talk about "components" are you meaning things like resistors and capacitors ?

Most capacitors will be marked with the working voltage and normal resistors are quite safe up to about 600V.

I build valve amps for a hobby and once the HT gets above 600v the component choice becomes more specialised, and expensive !

Can you photo those control boards ?


Philip.

Thanks for that comment Chuff Chuff - but where do we find that component and test it?

On the pre65 front I see that you are in the same era as my grandad who used to make radios and televisions with valves and bits. My brother is the electronics wiz in our family and he has been helping me test capacitors and diodes and resistors and relays from front to back, inside some pretty dark and cold cabinets and they all seem to check out OK.

Aaah Good question

I'll have to find me manuals

As Mr Oates said " I may be gone some time "

Trouble with 47's never put anything in the same place

I'm not actually in any hurry to climb back inside it just at the moment so you have plenty of time! Anyway the beast has been drained of coolant for the winter so we cant run it up and check for air or current until it warms up a bit. Thanks and happy hunting.

Knew there was something odd about them :D

There's 3 cocks on them

1) Ingoing
found in the Boiler Compartment No 2 End on the
Secondmans side just inside the engine room door on the left
by the CO2 bott

2) Outgoing
continue into Engine Comp and turn right and should be just before the
Battery Isol Switch

3) Equipment
Stand by B.I.S and look towards No2 cab, and it's in the Elec cupboard
in front of you, usually low down and against the cupboard front side

Hope this will help

Thanks Chuff Chuff. I have just imagined banging my head a couple of times but I am getting there. Could get a chance to look at this next weekend. Will keep you posted.