[Codythecreator]

Hey guys. I recently finished retrofitting my “new to me” hurco sm1 and have been playing around with it a bit, and decided it’s time to hook up the coolant pump back up. Problem is, I’m getting contradicting readings from my multimeter, as to which leads are which. Theres 6 leads, and 2 sets of leads read the same resistance, while the third set reads double the resistance of the other 2 sets. To me this means it’s single phase and the higher resistance windings are the start windings. But there’s no start capacitor or centrifugal clutch to support that theory. Plus it’s rated for 240v/480v ? So I was thinking it has to be 3 phase, but every 3 phase motor I’ve ever hooked up has 9 leads. So could it be a resistance start or split phase motor? Is it 3 phase, just with a bad winding causing the higher resistance ? (Even though it’s odd that it would be exactly double, much like how a start winding on single phase motor is) I’ve searched high and low to find this brand of pump and have found nothing, and also haven’t found any wiring diagrams to see if there’s a certain way it’s supposed to be wired. So if someone thinks they have the wisdom I don’t, I’d like to hear your thoughts. I attached a few pics of the nameplate and of the wiring Thanks in advance

[CitizenOfDreams]

It appears to be a single phase dual voltage motor. (The picture below shows a 115/230V example.)

[machinehop5]

...how waz the M8 controlling relay wired before ?
3ph coolant pumps was the standard some what back than and now for machining centers.

[Codythecreator]

The windings look correct, but im not seeing the capacitor in the circuit. Unless its a split phase or "resistance start" motor, but i thought those were more in ceiling fans and such? and this is definitely an induction motor.

[Codythecreator]

i couldnt tell you, when i bought the machine, the control panel looked as if it was wired by a kindergartener. and 1 panel was original componets (transformers, starting/reversing contactors, etc), and the other panel was someones attempt at a retrofit. So i had already decided i was going to pull everything and start new so i stupidly pulled everything from the panel with the original components so i could get the machine pushed up to the wall before i still had to return the lift. so long story short i rushed and didnt pay attention to how anything was wired in the bac panel since whoever tried rebuilding the machine before me had installed all the new components in the other cabinet. im leaning towards it being three phase since the machine was (and still is) 3 phase. i cant imagine hurco making the everything 3 phase except the coolant pump. the only thing thats throwing me off is the 3rd winding which is exactly double the resistance of the other 2, as if it is the start winding. As i commented above, the only single phase ac motor i know of that doesnt need a capacitor to start, is a split phase motor. but i thought they only pertained to things like ceiling fans and such

[CitizenOfDreams]

The windings look correct, but im not seeing the capacitor in the circuit.

I believe this is some sort of a split phase motor. Normally it would have a centrifugal switch, but I guess the start winding current is small enough to leave it connected permanently.