It is not always the loco chassis that is at fault, several issues can make a loco stall on insulfrog points and crossings, the problems are made worse with DCC control:
1: Points need to be laid as level as possible, It is worth your time using
the edge of a steel ruler to make sure that the rails are level all the way across the point/crossing, if the point is not level, a small locomotive with limited electrical pickup such as an 0-4-0 or 0-6-0 can have 1 or more of its wheels slighly lifted off
the track causing loss of electrical contact.
2: Clean rail and loco wheel treads are a must.
3: Make sure the rail joiners are tight.
4: Check the wiper pickups on the loco chassis, even down to cleaning the back of the loco wheels (where
the wiper pickup bears on the wheel).
5: It it is a 'tender drive' model, make sure the loco runs freely, and that the wheels are quartered correctly and not causing the loco to lift 1 or more of its wheels off the track as they rotate (I had this problem
recently). Also make sure that the connections between loco and tender are sound.
6: Diamond crossings cause momentary shorting problems, which under DC control would not cause a problem, other than a spark, can cause a DCC unit to trip out.
