POTD was reading the electrical cabinet wiring schematic for my Tormach 1100 Series 3 mill. As you can guess, if I'm reading the electrical schematic, I must of had a problem. . . .
Was setting up to run a part; locked it in the vise, probed a corner and top surface to set the coordinates, pulled the probe and hit CYCLE START. The auto tool changer grabbed the right tool, routine was about to start then everything went dark. . . All of my 115V "stuff" was dead. E-stopped the machine, shut everything off and fired it back up to no avail.
The computer controller, monitor and coolant pump all get power from the mill's electrical cabinet. I could fire up the stepper motors, but read nothing at the 115V outlets. I plugged the monitor and PathPilot controller into an extension cord plugged to a wall socket and they did fire up. I could also control the table/column/spindle from the jog shuttle/keyboard and touch-screen. That told me the controller wasn't fried, and it was communicating properly to the electrical panel and the machine control board.
Minor kludging to get back up and running. I plugged my coolant pump into a wireless outlet as it would have to be manually turned on/off until I figured out the real problem. Easy to hit an ON/OFF switch on the FOB to run the pump. Well, the pump wouldn't run. When I bought the mill, the previous owner used a 1/2 HP sump pump for coolant. Motor was very hot to the touch also.
Looking at the electrical schematic, the most likely suspect was a 6A fuse which protects the 115V circuits for the pump, monitor and controller. Sure enough, it was blown. I suspect the pump had frozen up and popped the fuse when the routine called for coolant to come on.
A look inside the Tormach 1100 electrical panel. The red LED lit up on the RH side indicates that fuse FU6 is blown. Guess I now know if the LED is on, that's a bad thing.
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I ended up replacing the 1/2 HP pump with a 1/4 HP pump and did some changes to the coolant system plumbing. The 1/2 HP pump was rated at a peak of 3000 gph, 1/4 HP is 1200 gph. I typically run coolant at less than 60 gph, so no issue with less max delivery.
The previous owner had plumbed the output of the pump to a house water filter, then a ball valve to control outlet flow. I questioned this at the time but didn't take any action as the ball valve was nearly choked off to get the flow at the outlet of the LOC LINEs to a reasonable level. I suspect the pump may have nuked from only getting 2% of its rated flow through the ball valve.
Green hose is the inlet. Coolant runs through a house water filter, then a 'T' to a wash down hose (blue hose) and then a ball valve to control flow at the mill's coolant lines. The valve handle at vertical is shut off, this is the position I'd normally run it in. If I ran high flow through the valve, it was really tough to regulate the coolant flow at the Loc Line valves. I even blew a Loc Line apart in the past leaving it at high flow.
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My original plan was to plump the output through a shower mixer with one line running to the mill's coolant lines and the other to a line back into the coolant tank. That way the pump isn't getting dead-headed as I choke down the outlet at the mill. Was digging through our garden hose fittings and found a better/cheaper mixer: a simple garden hose "Y". The pump outlet now runs into the "Y" with a hose going right back into the tank and the other to the original set up. The pump should run much happier now, though I believe some pumps can handle being dead-headed.
New coolant pump and the shower mixing valve for the original plumbing plan.
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Ended up running the pump outlet through a "Y" with one line going directly back into the coolant tank and the other up to the mill.
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No issues with coolant now. If I open the Loc Line valves completely open, it'll shoot coolant 6' away.
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Had to fab up an 'anchor' to hold the diverted line in the tank. Yeah, fired up the pump and shot the hose out of the tank
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Alas, no extra 6A fuses to get everything back to normal, but my work around is at least functional. Amazon says 3 days for replacements.
Thanks for looking,
Bruce
