Dapol A4 blowing decoders

[mikecu]

Has anyone had any problems with the Dapol A4 blowing decoders.

I have fitted two DCC23 decoders to the Dapol A4 N gauge loco and both failed after programming the loco number. The first I removed from a running Farish loco and fitted it to the Dapol A4 it moved the loco about 1/2" and smoked. the second tried to run but my ECoS buzzed and  tripped the overload protection. 

I have no problems on any of my other locos running on my layout.

[John ks]

Are the motor brushes isolated  from the track wires

 

if for example the right rail (red wire) is bridged to the motor + (orange wire NMRA standard) the loco will work on DC but when the DC plug is removed & a DCC chip is fitted there is a short between the rail & the output of the decoder & the magic smoke escapes

Ask me how I know

 

There may be solder bridging tracks on the circuit board or the uninsulated end of a wire touching somewhere it shouldn't

 

John

[doug22150]

Are the motor brushes isolated  from the track wires

 

if for example the right rail (red wire) is bridged to the motor + (orange wire NMRA standard) the loco will work on DC but when the DC plug is removed & a DCC chip is fitted there is a short between the rail & the output of the decoder & the magic smoke escapes

Ask me how I know

 

There may be solder bridging tracks on the circuit board or the uninsulated end of a wire touching somewhere it shouldn't

 

John

I recently has problems with a Dapol A4 which ran perfectly on DC power but which, after conversion to DCC, shorted-out on curves whenever run backwards! I found that the motor brush wires were shorting-out to the 3rd set of tender wheels because the brush-capacitor wires were too close to the wheels.  Once I had spotted this, I carefully bent the wires well clear of the wheels and the problem was completely solved!

 

Doug

[mikecu]

I returned the loco twice and they eventually found the problem, but didn't tell me what the cause was, justrepaired it and sent it back to me.