I changed my CNC from the spindle that came with it to a DeWalt DWP611 router to have a beefier device. So far, so good. I wanted to be able to switch it with gcode commands like I did with the DC spindle, so I built a control box with an SSR-25 DA solid state relay. I use 12VDC from my CNC electronics box as the control signal for the SSR, switching it with an isolation relay in the CNC box. It works just fine - mostly. Actually, the process works great but I doubt I would have noticed an issue if the DWP611 didn't have LEDs on it. The router switches off as commanded but the LEDs remain illuminated at a low level. Making some voltage measurements, I see about 30VAC at the output of the relay when it is "OFF". The input control voltage measures 0VDC. I know SSRs have some leakage. Apparently, the internal resistance of the output side of the relay is such that some voltage is passed but at a very low current. Is there a simple way to defeat the leakage?
Edit: The switch box I built is for the purpose of turning on the router and shop vac when the CNC cut starts.