Bridgeport Interact 1 MK2 - Input Voltage

[machintek]

Are you running on a phase converter?
If the artificial phase is attached to the control it will pull down when you try and start the spindle motor. The "wild" phase should only go to the spindle motor.
Have you put a meter on each phase as you engaged the motor?

George

[seki]

No phase converter - I have three-phase utility power. I'll try the meter on each phase.

Thanks, SK

[machintek]

I wonder if the motor is wired correctly. There are 9 wires that configure the motor for 230 or 460 volts. I would measure the resistance of how it is wired to make sure that all three wires going to the motor have the same resistance. This of course is done with the machine OFF.
The other item that comes to mind is wires too small so that the wall cannot supply the power the machine needs when the motor starts up and thus the voltage drops.
The air brake releases, right?

George

[seki]

Yes, the air brake releases, and I can turn the spindle by hand with the brake off. The connections at the motor are correct for the supply voltage. I'll check the wiring resistance - good idea. I am starting to think that this sounds like a motor starter problem. There is a bootlegged starter in there, wired up in parallel with the original equipment. I found a site that explains magnetic starter operation:

http://wiki.owwm.com/Default.aspx?Pa...ing%20Diagrams

so I'll be checking that, too.

Thanks for your advice. I'll let you know when I either get it fixed or run out of ideas.

SK

[machintek]

All of these machines have contactors that turn the motor on forward and reverse (swaps two phases to achieve this) and have a overload. I wonder if it is original and wired correctly. Typically there are piggy back switches on these to disable the opposite direction contactor to prevent a direct short which would happen if both came on at the same time.

George

[seki]

The piggyback switch on one of the contactors was bypassed to an added-on relay. The main motor contactors are made by Yaskawa, and almsot everything else in the wiring cabinet is German. I am looking for a wiring diagram so I can see if everything is at least hooked up properly, and to help me troubleshoot voltages and continuity. The reverse contactor has an overload device on it, and the bypassed contactor does not. Plenty of things to check, that's for sure.

[machintek]

Attached is a set of wiring for a INT2S2 with a TNC151. you will find it very similar.

George

[seki]

Thanks! I'll keep you informed of progress.

SK

[seki]

Here's the latest. I took both the forward and reverse starters out (one at a time), cleaned the contacts, and got rid of the piggyback relay which was probably there to bypass a nonfunctional set of contacts. The machine behaved no differently. I took the back off the computer pendant, and there was a voltage selector in there that was set to 140. Is that a European line voltage? I set it to 120, and voila, the motor started and ran and the computer didn't shut itself down. There are other problems, such as a not-working speed control, but progress has been made. Thanks again everyone for all your help.