Hi all,

I've purchased a China CNC 6040 with XHC mks v control board. I'm trying to setup a solenoid to control cooling but unfortunately so far despite lots of reading I've been unsuccessful.

I'm using Mach 3, which already has flood/ mist control assigned to output 4. This is ideal I thought, wire up the relay to the control boards 5V output then use output 4 to turn the relay on/off.

However when I use the M7 gcode to turn the mist coolant on nothing happens, I've measured the voltage and on it measures -0.5V and off 0V.

I'm completely lost as to why the voltage on output 4 is not high enough to activate a relay.

Does anyone have an idea as to what is wrong or anything else I should do to get coolant running?

Please see the attachment images

Many Thanks

Colin