A-B-A set, new problem

The problem is either in the trailing A unit, or it is in the tether between the units. They could have melted causing one wire to touch another inside the tether.

The fact that the trailing A unit acts badly when disconnected from the rest of teh set points to something inside the trailing A.

It sounds like the B unit can be eliminated as a source of problems.

RoyBoy:

Thanks for the reply.  I tried running the set conventionally.  At .5 to 1.0 volts the trailing "A" unit starting moving, while the lead "A" unit was not yet responding to track voltage. 

I tried yet another Factory Reset.  It reset, but as soon as I set 1smph in DCS, the trailing "A" unit went to full power.  It's like its lost its speed control.  The lights on the trailing "A" unit respond properly to the remote.

The slave board went bad in the trailing A unit. Only repair available is to replace the board. Sorry for the unpleasant news.

Chuck

Thanks for the reply.  As I suspected.  This is the second time that I've had a locomotive fail right out of the box.

Will contact MTH tomorrow for an RMA.

Rick

The cheapest fix (if you don't actually need the extra pulling power) is to turn it into a dummy and just drag it around. Save what electronics are good and the motors for later use. 

This is a brand new set (purchased Monday).  

I'm hoping that my dealer, who has another set, will swap the defective unit with a new one, then send the bad one back to MTH for repair.  

Otherwise I'll box her up and get an RMA, then see what MTH can do for me.

The derailment has damaged (shorted) the motor FET on the slave board most likely.  This is a common issue with PS-2 Slaves and the board can be repaired vice replaced.

I have not had a repair on a PS-3 slave yet, but it does have FETs so I hope it can be repaired vice replaced.

Warranty is the way to go on this.  G

GGG

Other than never having a derailment is there a way to protect the slave unit so this doesn't happen again after repair?  I'm hoping that lengthening the tether so that it no longer impinges on the drawbars will prevent the derailments from continuing.

The lead "A" and the "B" look fantastic pulling the passenger set.  I did repaint the truck side frames silver (they were painted gray when built) and the whole A-B-A sets looks much better.

Oops! I missed the part about it being brand new. You are correct, the whole A-B-A unit looks fantastic. I have an MTH Canadian Pacific unit which I use in front of a passenger consist.

Tried running this locomotive by itself under conventional control.  It moved one to two feet, then stopped.

I noticed sparking coming from the two wires attached to the top of the rear truck that are attached to the rear pick up roller.  Couldn't find a reason for the sparking.  Now the locomotive doesn' respond to,conventional track power at all.

Called MTH Service this afternoon, and was told they only take calls from customers on Tuesday, Wednesday, and Thursday from 12 to 5 pm.  Will have to wait until at least then for an RMA.

Purchased Tuesday, dead today.

I had a PS 2.0 slave board on an MTH E-8 trailing A unit fail twice due to bad wiring on the fixed male tether connector right out of the box on the included B unit and the additional B unit I purchased.  Both were covered under warranty.  The MTH repairman hot glued the 10 soldered wires in place and I have not had any problems in six years.

Good Luck!

Chas  

Over the weekend I posted this issue on the MTH service page using their "Contact Service" link, and received a response in the fom of an RMA. 

They also indicated that right their estimated repair time is 6 to 7 weeks.  Wow!  I'm guessing that either this is the post Christmas rush, or they are short-handed in the repair Department.

A half-hour of running in exchange for two months to ship, repair, and return is a poor exchange rate indeed.

Sorry for your misfortune. The best thing to do is ship it off and not think about it.

Have you thought about installing a set of TVS to protect these units?

 "transient voltage suppressor diode"

J Daddy:

Not until just now.  I did ask the question of MTH "How do you protect the engines from this problem?" but received no reply.

Where within the engine would they be installed?  Would I be correct in thinking that each engine would need one at each pick-up roller, or is there a central location (power feed to the control board, for example) where they would go?