MSD043A1XXV Panasonic AC Servo Driver 400w - MB3 connection help

[Doddy]

Hi, just managed to get back to this...

Still having a problem with where the 24v Power should come from for the servos. My problem is that the the Y316 input will only sink 70mA. Could someone please explain what would be the safe way to do this without me damaging the servo and/or MB3.

thanks

https://industrial.panasonic.com/con...s_manual_e.pdf is my "source of truth" here - please confirm yourself that it's applicable to your servo drive.

From that link, page 11, fig 6-1-1 shows the intent of the 24V supply - though in that link it's referred to as COM+ and COM-, and specified as 12-24V. This is the feed to the isolated inputs to the servo driver, and the purpose is entirely to manage that interface. For this, use the same 24V supply as you use on the MB3 for the servo COM+/COM- pins. If you look at the schematic in 6-1-1, you'll note the series resistor on the opto-isolator inputs - 4k7, a quick bit of Ohms law resolves that as you need a sink capacity of around 5mA per input, so with your schematic with the MB3, Y316 needs to be able to sink 5mA - it's rated at 70mA, and will be fine. (I'll not bore people with the maths here, by all means IM me if you need that explaining, Nemo.... oh, looking up, I think I did in the earlier post).