I went to start work this morning and after hitting cycle start the coolant pump did not come on. Shut down and start investigating, I could hear the relay when I cycled the flood coolant. I found the F1 fuse blown. I replaced it and the pump still doesn’t start but I now get a humming from the pump. I was able to switch it over to the mist coolant outlet to finish the job but want to fix it correctly. I am looking at the Tormach troubleshooting which has you jump J5-1 to J5-2. I will go down that rabbit hole tomorrow.
Has anyone seen this before?
UPDATE: I was back in the shop last night for a couple voltage measurements and and somewhere in my poking around cleared the issue. So I believe it’s a connection issue which I will explore further today or tomorrow. I wasn’t clear in my OP that I’ve mostly ruled out a problem with the pump itself as it runs fine when connected to the mist coolant power source.
I had a pump fuse failure in the past week. Powered down. Replaced fuse. Powered back up. Activate coolant button in PP UI. Pump operates again. I know why mine blew (OE fuse was too small for the upgraded pump).
The question is why did your fuse blow…
Normal fuse failure due to age/expected failure from usage
Pump has chips in impeller (and it overloaded and is making that sound)
Motor has a problem not related to blockage
You would think #2 or #3 would blow the new fuse. The noise could be that the motor is just having trouble starting to rotate but that seems unlikely without there being some other problem present.
If you are getting humming from the pump then it’s likely a mechanical issue instead of a an electrical.
Check for blockage, make sure the pump is actually turning, disconnect the hose from the pump output and check for coolant flow.
Hi Ashraf, all great points. And I have the same questions. When it first happened I suspected the pump so I pulled the coolant tank out and tried to spin the motor by hand. I was suspicious a chip was stuck in it but it turned freely and as I said in my update works just fine on a different power source.
I misread that point on you swapping the outlets and the M codes to finish your job. I read it as you switched to MQL to finish the job (and not switching outlets for the flood).
Stupid question but did you change the fuse to the appropriate size for the plate on your upgraded 1/4 HP pump? There are fast (cheap) and slow blow (expensive) fuses for these industrial holders and the open the circuit at this amperage is different for each type of fuse.
You already did this but yeah, sadly, it seems like if it happens again you:
Disconnect power input to the circuit and ohm each point from source to target and wiggle/test connectors/wires
May have to do the same with voltage applied
The relay in theory should either work or it won’t. Going bad could be partial circuit and high resistance where the pump motor is straining to start. Same for any sort of high resistance from source to motor.
Yup have the right fuse. Did a wiggle test under load this morning with no adverse results. If it happens again I will have to ohm everything out as you said. I am a little suspicious of the relay contacts, the coil side worked fine the whole time. It’s always something!
