[endgrainguy]

I'm trying to start/stop a spindle in Mach3 using relay board. I don't understand why it isn't working. When I do the "toggle spindle" routine on the diagnostics screen described in Mach3 set up manual I can get my wires to go from 0 to 3.9 volts, and the screen indicates "input 1 " as functioning, but it won't start the spindle. I've tried both active high and low settings. But when I hook up 5 volts, or even 3.3 volts, from a seperate source to the relay's 5 volt input (instead of the wires coming from my BOB), it works. Can anyone explain this or help me? Thanks!

[Ch_Irawan]

If you drive the relay directly from parallel port then probably there is not enough current from parallel port to actuate the relay.

-ichan

[endgrainguy]

The relay requirese "5 volts". I tested it with a seperate power supply, one of those switch adjustable ones. It started at both 5 volts and 3.3. My meter says the wires coming off my BOB carry 3.9 V when switched "on" , but it is not starting the relay. Are not all volts of the same quality? I don't understand why this isn't starting. I"m not using a charge pump. I don't even know what a charge pump is. Do I need to use one to start 12 amp router with Mach3? Somebody out there must have a greater understanding of this than I do. It wouldn't take much I'm afraid!

[endgrainguy]

Actually I tested voltage of wires coming of BOB again. They measure .09 low and 3.8 high. Could this be the problem, and how addressed?