Problem with Boxford TCL lenze controller

[John11668]

Turns out that when I blew the cheap chinese controller I took out the Bob too, so when I installed the new driver strange things went on including motor running slow , pulsing on and off . When I checked volts at the relay and pot terminals the motor started and the circuit breaker in the machine blew. Alsofound that the the Bob relay was continually made . Replaced BoB and tried again and this time the controller does not work at all . I dont know whether it is duff or whether I have blown that too. They are unisolated units with a floating pot input like lenze so not suitable to connect the pwm direct from the computer . I hadnt been bothered as I hoped to use the DIYCNC board to overcome that but now when ordering a replacement and after some consideration I have decided to go for this .
https://inverterdrive.com/group/DC-T...0-Isolated-1Q/

A bit more pricey but will take the computer pwm output
Arriving tomorrow so will have another go then.

[John11668]

Amazingly the new driver arrived today ( Sunday lunchtime via Dpd) so installed and tested .
Works a treat.
It is neat, isolated so should work with pwm staight from BoB , and has lots of options for trimming ramp speed, max speed max current so all in all I am pleased with it .

Having some difficulty getting the spindle speed control working in Linux . (am sure we will get there) but going back to mach tomorrow just to prove to myself that The spindle index function is still working OK there , in which case it should be configurable in linux.

One thing which concerns me and am not sure if it is my mistake , but if I havent yet switched on my computer but have switched on the machine , the spindle relay is energised ,
This means that the spindle runs with no call for it to do so .
Is this a general problem or is it me ??
Why is the spindle relay energised when there is no demand for that.????