faulty motors

[Curly 52]

polarity is the same on all parts of the track . both locos working fine this morning ..

while on the forum how ofton would you recommend lubricating the locos , the paperwork suggests 100hrs or 6 months, many thanks

[Brew Man]

Six months sounds reasonable to me.

[ntpntpntp]

Lubrication really does depend on how much work the model does. There is no need to stick to a schedule. Over-lubricating causes as many problems as a lack of lube: over-oiling was often the problem with models when I used to do a "loco doctor" desk at my club's exhibition. Lubricate only when the model needs it (for example when high speed bearings start to "scream"). Make sure you use appropriate plastic-safe thin oil or grease, and then only the tiniest amount on the tip of a pin. If you can see the oil it's too much.

Generally I'd say my locos get a service and lube check once every year or so, but then I'm not running them daily. Some probably go for 3 years or more without a service unless a problem arises.

[Brew Man]

I can concur regarding over-oiling. I bought an Adams Radial once from Oxford Rail's eBay outlet. When I took the lid off I saw to my horror that the whole chassis was swimming in oil. Still haven't got round to cleaning it up. I'm sure it will be fine when I do.

[Rallymatt]

My experience of Hornby TT:120 locos is they are on the very well to excessively lubricated side at the factory. Lubrication requires the right one for the job and tiny amounts, applying it with a pin is a great way to prevent over doing it.

[Fishmanoz]

polarity is the same on all parts of the track . both locos working fine this morning ..

 

 

I second Curly’s conclusion on track polarity.

Take another look at his power connecting clips. They connect to the same side of each loop and clearly connect inner loop track A to outer loop track A (and B to B). The fact that the single controller power feed comes from the other side of the track is completely irrelevant. Changing the crossover points from straight ahead to crossing will not cause a short.

Happy to be proven wrong on this but don’t think so?

[Hobby11]

With such issues it's best, as I suggested, to go back to basics and do a process of elimination, hence I said to remove the inner circuit altogether. Rule One of Fault Finding. Then run the locos and controllers and see what happens. If nothing then it's a fault with the wiring or faulty points.

However it seems people just want to overcomplicate things. I give up.

[Rallymatt]

@Fishy, it’s not great to establish from photo but the two linked clips appear to have the wires transposed. The clip to the outer loop has a black wire feeding to the left terminal (short prong) where as on the clip on the inner loop appears to have the black in the right terminal (long prong) As I said, it’s hard to 100% from photo and I am assuming it’s a straight jumper wire between the two loops.

I do agree with Hobby that in light of so many failures it would good to strip right back and test from a basic oval and move forwards.

[Fishmanoz]

I’m not convinced of that RM. For a start, the part in the shop shows it with a cable fitted so, if it is as you suggest, factory fit on each clip is different.

But … the clip on the outer loop has the cable emerging with a clockwise twist while on the inner loop, the twist is anticlockwise. This may be giving a wrong impression.

Maybe someone who has the clips can confirm? And see questions I’ve asked Curly 13 hrs ago in his other thread.

[moawkwrd]

My digital power clip has black and white cables, with white being on the right hand side. I assume the analogue one is the same (with a small capacitor added like the power track)?

But there is room to twist them such that it could appear the other way around.

[Brew Man]

I believe this faulty wiring theory is a complete red herring that will lead nowhere. If there is a short, any current will bypass the motor. If there is an open circuit, then, er nothing will happen. My money remains on the controller being faulty

[Fishmanoz]

Both controllers faulty?

And despite all Curly’s track voltage readings being normal? Although if an intermittent spike big enough to burn out a motor, maybe he hasn’t measured during it.

But again, both?

[Brew Man]

I suppose it would depend on how old the controllers are. But two faulty controllers sounds more feasible than umpteen faulty motors. I agree though, it is a strange one.

[Rallymatt]

It’s one of those frustrating situations where you would really just want to be in front of the layout and work it out.

AFAIK, one controller was the Easterner Set ones, so not old.

Another consideration is, have motors ‘actually’ failed electrically? Or has it been an associated part failure and Hornby replaced motor as a precaution. I know on both occasions for me, the thing as seized solid, ie no backlash in the drive at all, which would kill a motor ultimately.

[Simon-372339]

Possible but is it likely or is my thinking rubbish?

With both ovals connected to the controller

Oval 1 with train running at moderate speed draws 0.3A

Oval 2 no train wiring fault/track issue draws 0.3A

So total 0.6A wont register on the controller as short circuit etc

Oval 2 fault is intermittent, vibration from running train resolves it.

Controller is outputting 0.6A the full load which now goes to the train.

Amp values plucked out of thin air for example purposes.

[Curly 52]

new controller GM 100M is only 1 month old

[SMR248]

Simon, to quote someone else on here "That's not how electricity works".

All things being equal, the loco will only draw 0.3A (Ohm's law) regardless of what's happening on the other track.

Assume that the voltage, governed by the controller setting, is 9V. Assume that the resistance of the loco is 30 ohms. Resistance is a constant(ish). I=V/R so the current is 9÷30 = 0.3A. If the voltage changes due to moving the knob, then so will the current.

[Simon-372339]

I'll rephrase my previous post to hopefully make it clearer.

If we have a train on oval 1 and one on oval 2, would the train on oval 1 speed up if train on oval 2 was removed, assuming the controller knob wasn't changed and both ovals wired to same controller?

[Fishmanoz]

Simon, short answer is no. Loco responds to volts.

Remember, Curly has been running only one loco at a time with the other parked in a siding. And if I read him correctly, he has only 3 - Easterner plus 2 x 08s, one with Hornby under warranty, the other recently burnt out.

[Daedalus]

Electric motors DO NOT obey Ohm's Law. The most likely cause of a burnt out motor is a mechanical failure of some sort preventing the armature rotating and drawing excessive current.

[SMR248]

Assuming that all things are equal they DO!

My post was in response to Simon's question.

I agree with your second point though. If you put a spanner in the works then the motor will rapidly overheat, insulation will break down, the resistance will reduce, etc...

[SMR248]

Simon, I understood your question the first time round and was trying to be polite by not giving the obvious response...

Sorry that you didn't understand my response...

[Curly 52]

up date, Easterner still running ok on outer track no problems. repaired shunter coming back today will run that for the next few days, inner track disconected electrically

[Daedalus]

Electric motors DO NOT obey Ohm's Law they are not resistors. A back-emf is generated that varies with rotation speed, load and various things like the fluctuation of magnetic field caused by the commutator, strength of the magnet etc. Good luck calculating that with Ohm's Law.

[John-L]

I just noticed the description mentions the track is screwed to the board? It’s a bit of a left-field idea but were the screws applied using a power screwdriver? Is it possible there is some metal swarf from the screws polluting the track?

If some tiny pieces of metal from those screws were to get into the wheels of the loco and then short out the motor?

Or if the screws are large enough to touch both wheels, or to hit the chassis of the loco they could cause a short?