problems with driver

[F2DVasek]

Good day!
That's the problem:
One of the drivers (M880) gave an error (red LED lit)
Power turns off, the error remains.

It all started with the fact that this driver, the machine is the steps the other axis are working properly.

First, the driver turned the engine, the engine lost a step and buzzed .....
Then he got up and did on the driver lit up red light ...
rearranged the engine to the other driver, the engine began to fall apart ... just did not experiment further (in order and this driver is not lit red).

And to put another driver predyvduschy engine light ... red and burning.
If the engine off, lights green.
Wire rang, what else can you do?
And that could burn?



Same garbage with another driver .... the engine revs at a very small cliff, when changing the direction of rotation of second driver passed out.

[F2DVasek]

Can someone help with my problem?
If you need more data, say, I will write.

motors without load, while testing only.
Voltage tested many times, 65 volts.
motors for high speed spinning normally, when tried on the small, the driver fails.
All wires are tested more than once, everything okay, and check the connection under the scheme.
The driver crashed it at low speeds.

[James Newton]

Your English is difficult to understand.

If stepper good at high speed, and bad at low speed, then the problem is mid band resonance. Reduce the power supply voltage. Add a resonance damper. Select microstepping mode.

[F2DVasek]

shorted contacts "+" power driver and terminal "A +".
How can I fix it?