Possible electrical issue with new G9972Z lathe

[Road_Clam]

So i'm observing an odd issue with my new lathe. When I power up the lathe pushing the green power button, I then attempt to rotate the spindle "L - R" switch to either rotation position and I see the spindle rotate a tiny bit and then nothing. I have to put the spindle switch in either L or R position FIRST then press the green power button for the spindle rotation to start. Seems like some type of internal circut breaker keeps tripping off when I try to use the spindle switch. Are you supposed to be able to flip the spindle switch back and fourth between L and R while the lathe is powered up ? If I continue to press and hold the green power button then I can switch back and fourth with spindle rotation and the spindle turns as it should. I'm confused as to what's going on. Sounds like by reading the manual you should be able to switch rotation direction under power via the spindle switch.

 

[Jim F]

Page 19 of the manual says to wait for spindle to stop before changing direction.....
Good practice with a threaded chuck.

 

[Mitch Alsup]

Only machines on 3-phase power can reverse while the major component is spinning.

 

[WobblyHand]

Have an earlier Grizzly. G0752Z. I push the green button to start. Wait a little and turn the F/R switch to either F or R, but not flipping one to the other. Spindle rotates in the correct direction. To stop, can push the STOP button, or turn the F/R switch in the middle. If turned to the middle (neutral?) the lathe spindle rotation can be started again by changing the F/R switch position.

My lathe will not start up if the F/R switch is not in neutral. Safety. This is a good thing. Read the manual, there is a lot of stuff hidden in there!

 

[Road_Clam]

OK, let me further clarify, i'm clear on the fact you need to wait until the spindle is completely stopped before reversing the switch direction. My issue is happening when the spindle is completely stopped.

 

[WobblyHand]

Ok. Let's' start over again. Lathe power is on. Switch is in neutral. You turn the switch to F(orward) normal rotation. What happens?
The spindle rotates a little then stops rotating? Or what? If it stops, is the power to the lathe still on, or do you have to turn it back on again? The more succinct your description, the easier it is to help.

By any chance does your lathe have a VFD? Are you plugged into a GFCI outlets? Might as well ask the question.

 

[Road_Clam]

Ok. Let's' start over again. Lathe power is on. Switch is in neutral. You turn the switch to F(orward) normal rotation. What happens?
The spindle rotates a little then stops rotating? Or what? If it stops, is the power to the lathe still on, or do you have to turn it back on again? The more succinct your description, the easier it is to help.

By any chance does your lathe have a VFD? Are you plugged into a GFCI outlets? Might as well ask the question.

The spindle won't power up and turn with this sequence of conditions. And if I keep the switch in the "F" position and push the green power button the spindle then starts as it should. It's becoming clear to me there is some type of internal circuit interrupt fault that keeps tripping and seems to be associated with the "on/off" main switch. Lastly no VFD and no GFCI outlet power supply. The circuit is adequate as I also run my air compressor off the same circuit. I'm going to give Grizz tech support a call and see what they say. I just want to make sure that i'm not incorrectly operating the power controls.

small world, we are practically neighbors...

 

[WobblyHand]

The spindle won't power up and turn with this sequence of conditions. And if I keep the switch in the "F" position and push the green power button the spindle then starts as it should.

Does the spindle stay on? You haven't explicitly stated that in this description. We aren't in the same room, so we need to make sure we understand. It starts then quits after a while?

It's becoming clear to me there is some type of internal circuit interrupt fault that keeps tripping and seems to be associated with the "on/off" main switch.

Lastly no VFD and no GFCI outlet power supply. The circuit is adequate as I also run my air compressor off the same circuit. I'm going to give Grizz tech support a call and see what they say. I just want to make sure that i'm not incorrectly operating the power controls.

I just downloaded the manual. It seems the operating procedure is different from my lathe.

You are quite correct that you turn the spindle direction first, then the power. Are you saying if you do this the motor stops after a second or so?

Schematic looks simple. Maybe a bad run capacitor or faulty switch? Don't see any interlocks.

 

[Bi11Hudson]

What he is asking about is the speed control vs power on circuit. It is common on small lathes and milling machines where they must start at lowest speed. That has to do with the design of the controller board. Presetting direction before starting is preferred even on three phase. Presetting speed before starting is akin to starting an auto. The speed control must be at the lower end to start. I have a mini-mill that is used as a drill press for small drills where speed must be below 60 RPM to prevent melting through plastic. I had given some thought to eliminating that start-speed function but realized that most of my work is at low speed anyway so why bother. It may have some relation to safety or making the board with a lower component count, I don't know. . . or care. I don't like it but can't create the gumption to do anything about it.

.

 

[WobblyHand]

What he is asking about is the speed control vs power on circuit. It is common on small lathes and milling machines where they must start at lowest speed. That has to do with the design of the controller board. Presetting direction before starting is preferred even on three phase. Presetting speed before starting is akin to starting an auto. The speed control must be at the lower end to start. I have a mini-mill that is used as a drill press for small drills where speed must be below 60 RPM to prevent melting through plastic. I had given some thought to eliminating that start-speed function but realized that most of my work is at low speed anyway so why bother. It may have some relation to safety or making the board with a lower component count, I don't know. . . or care. I don't like it but can't create the gumption to do anything about it.

.

This lathe doesn't have a speed control circuit. The speed is controlled only by the pulleys and the base 1725 rpm motor speed with internal centrifugal switch. There is no rheostat or pwm circuit to change speed. There are 6 spindle speeds, 150, 300, 560, 720, 1200, and 2400 RPM. Page 65 of the manual shows the wiring diagram. Has an on off switch, a spindle switch, a start capacitor and a run capacitor, that's it for electronics.