Retrofit utilizing existing power supply for Mesa Field Power

I’m working on a ~1978 Wells Index 700 CNC utilizing the original stepper motors. I was going to use the existing power supply for stepper power 45vdc. The original supply also has a very steady 24v output from a regulator board. Would it be safe to use the old power and regulator board for field power in to my 7i76? If so do I need any additional protection?

How do I supply field power when the ramp up rate must be less then 10v/millisecond Without switch or relay? The 24v is active once the power toggle switch is turned On.

That should be fine for field power, as long as the DC side is not switched

thank you, so I should bypass the toggle so DC is always hot when AC In is activated?

Yes if the switch is on the DC side, if its on the AC side, its fine.