24 Volt Signal Power

[I'mClueless]

Hello,

My CNC milling machine uses 24 Volts for the spindle run CW and CCW signal. I have added a Bijur cyclic lube system (electric motor drives a cam that operates the plunger) and I don't want the pump running when the mill is setting idle. The typical set up is to only provide power to the pump when the spindle is running. Thought it would be a simple matter of using a couple of diodes to prevent power feed back from the CW to the CCW signal and vice versa. Got that all wired in and without the Omron relay, MY2N-D2, coil connected everything works as it should. Connect the MY2N-D2 24 Volt coil and the spindle won't run. (yes I have the polarity correct on the coil) It is quite obvious that the coil causes a reduction in the signal voltage. Do I need to add some resistance in the 24 Volt power to the MY2N-D2 coil? If so then how much?

Yep, I'mClueLess

 

[carbonzit]

If the relay coil is causing a voltage drop (I ASS-U-ME that's what's happening, from your description), you might try a solid-state relay instead to run the pump, which won't load the circuit very much.

 

[bryan1]

There should be spare outputs on the cnc control board so I'd just use one of them then program when the spindle starts in either direction the lube pump turns on and turns off when the spindle stops. With my homemade cnc I made an option to turn on a vacuum pump by using a spare output and a simple command in the g-code will do it reliably everytime.

Cheers Bryan