loss of power to class 47 traction motors

[klordger1900]

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?

[ROUGH TOR]

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

[steam for ever]

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.

[klordger1900]

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.

[pre65]

Originally Posted by klordger1900

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.

[klordger1900]

Thks Philip. Correct on the loco no. too.

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

Sorry to say its not my loco!!!

[chuffchuff]

Control air Isolating cock shut.
Stops the reversers working

[klordger1900]

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!

[pre65]

Originally Posted by klordger1900

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.

[klordger1900]

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.