Is this a 3 Phase Static Converter?

Can I run 4 wire twist locks and still have "thermals"? I've got a large box full of 3phase and 1phase twist lock plugs.
A) you will only need a single phase plug for input power to the converter box, the twist lock will not interfere with heater selection or use.

Is a "thermal" a fuse?
A)NO,Daryl. a thermal is a device that breaks electrical contact when the circuit is pullin
g too much current. they are also called heaters.

Is a "fused disconnect" a small sub panel with a circuit breaker?
A)Fused disconnect by definition uses fuses to disconnect an overloaded circuit. a breaker provides the same function but rather than have a replaceable overload it has a manually reset one.

I've got an Ohm Meter, a gift from an electronics guy many years ago, supposedly a good one. No idea how to use it, other than for continuity checks.
I'd like to get the Gisholt electrical problem resolved. Up until May I could run it all day without any interruptions.
A) Daryl you may want to take a look and an amp draw on the Gisholt motor, the thermal overload may be tripping if the motor gets too hot. Remember that as a motor heats up the windings inside are less efficient at carrying electricity, the more resistance the less performance is possible.

- - - Updated - - -

Wired her up.
After the dust cloud cleared from the motor vents (hmm... doesn't smell like smoke), she purrs like a kitten.

Thanks for your help!!

Daryl
MN

Glad to hear she's up and running
how does she sound???
Have you attempted an amp draw test??
mike
 
Bob and Ulma Doc,
Thank you for your considered response.
I believe I actually understood it (that is not to suggest that I could do it). With the exception of the above.

Can I run 4 wire twist locks and still have "thermals"? I've got a large box full of 3phase and 1phase twist lock plugs.
Is a "thermal" a fuse?
Is a "fused disconnect" a small sub panel with a circuit breaker?

I've got an Ohm Meter, a gift from an electronics guy many years ago, supposedly a good one. No idea how to use it, other than for continuity checks.
I'd like to get the Gisholt electrical problem resolved. Up until May I could run it all day without any interruptions.


Thank you,
Daryl
MN

Daryl,

I think we can help you but we need more info here, I am asuming the Gisholt is also a 3 phase machine with a converter, if so what type of converter? or is it single phase? Does it start again on it's own after it quits, with you doing nothing other than restarting it with the switch? IE: Do you have to push a reset button to get it going again?

Bob in Oregon
 
Could you provide the information stamped into the label on the motor?

That should provide the Frame size, voltage, amperage, horsepower, and phase.

In my humble experience from what I see in the picture is a contactor, a plastic cased STARTING capacitor and a metal cased RUNNING capacitor, and nothing else. This indicates a single phase unit. This is why we need nameplate information as some units made to supply third leg power use the same components. I paid almost $200 for one to operate a 1/2hp drill press, nothing but a pain in the a$$. Would stall out, would not start, just rattle and buzz sometimes and when I talked to the maker he said I could not return it as they did not accept "USED" electrical devices. How is that for a kicker? I then spent $235 for a 1ph to 3ph VFD and the world is great. Plus I now have infinite speed control, overload protection, and reversing at the tip of my fingers.

What all did you do to get it to run?
 
Could you provide the information stamped into the label on the motor?

That should provide the Frame size, voltage, amperage, horsepower, and phase.

In my humble experience from what I see in the picture is a contactor, a plastic cased STARTING capacitor and a metal cased RUNNING capacitor, and nothing else. This indicates a single phase unit. This is why we need nameplate information as some units made to supply third leg power use the same components. I paid almost $200 for one to operate a 1/2hp drill press, nothing but a pain in the a$$. Would stall out, would not start, just rattle and buzz sometimes and when I talked to the maker he said I could not return it as they did not accept "USED" electrical devices. How is that for a kicker? I then spent $235 for a 1ph to 3ph VFD and the world is great. Plus I now have infinite speed control, overload protection, and reversing at the tip of my fingers.

What all did you do to get it to run?

Blew large dust clouds out of the motor vents (more came out when the motor started), made sure she was grounded, attached a 220v 20amp 1ph plug to the line (green is ground), got the fire extinguisher ready, plugged her in and flipped the switch.
 
Could you provide the information stamped into the label on the motor?

That should provide the Frame size, voltage, amperage, horsepower, and phase.

In my humble experience from what I see in the picture is a contactor, a plastic cased STARTING capacitor and a metal cased RUNNING capacitor, and nothing else. This indicates a single phase unit. This is why we need nameplate information as some units made to supply third leg power use the same components. I paid almost $200 for one to operate a 1/2hp drill press, nothing but a pain in the a$$. Would stall out, would not start, just rattle and buzz sometimes and when I talked to the maker he said I could not return it as they did not accept "USED" electrical devices. How is that for a kicker? I then spent $235 for a 1ph to 3ph VFD and the world is great. Plus I now have infinite speed control, overload protection, and reversing at the tip of my fingers.

What all did you do to get it to run?

If I may ask what brand VFD are you running? Are you happy with it then? Easy to program? I want to get a good one the first time, I have been considering the TECO brand?

Bob in Oregon
 
I have used many brands. Probably my favorites are Allan Bradley and Telemequnec, (new name for Square D). I have never used a TECO but from what I hear and read they are a pretty good unit. Lets face it, any brand is only as good as the man you buy it from. If they back their product one hundred percent then you will be happy because the outcome will be positive. TECO I believe is a Westinghouse product. I am a retired electrical contractor who primarily dealt with industrial accounts. The customer usually supplied the VFD and we merely installed and programmed them. Yes Sir. Installer of many, Master of none.

My shop has both the AB and Tele units and I can not brag one over the other. The AB does have a few little features that make them more user friendly to non professionals. I use five, Rockwell band saw, Bridgeport mill, home made wood lathe from a junky Craftsman, Walker Turner radial drill, and Delta drill press. I used some for the speed control such as the wood lathe and mostly the others to get three phase from single.

Jump in and try the water, you will love it and if you have problems I would be glad to help. If I don't know how to fix the problem I can usually ask the right question the right way to get the answer. I have never given up yet! Send me a personal message if you wish as I don't always check back to all the same places.

Good luck and good machining!
 
Found what is labeled a "thermal" in the Gisholt's electrical panel next to the magnetic switch. There are two thermals.
One of them has little bubbles/blisters on the sides. Similar to what you would expect from paint that has gotten hot.
I expect this is a problem.

Next question:
What causes a thermal to go bad?
Do they age out?
Will a new one burn out due to the real problem?
How do I best learn the real problem?

From this thread it could be the incoming power, my phase converter, or the motor.

Guess I'm also going to need to learn about reading an ohm meter.

Drat, more stuff to learn! More shop time!

Thank you,
Daryl
MN
 
Found what is labeled a "thermal" in the Gisholt's electrical panel next to the magnetic switch. There are two thermals.
One of them has little bubbles/blisters on the sides. Similar to what you would expect from paint that has gotten hot.
I expect this is a problem.

Next question:
What causes a thermal to go bad?
Do they age out?
Will a new one burn out due to the real problem?
How do I best learn the real problem?

From this thread it could be the incoming power, my phase converter, or the motor.

Guess I'm also going to need to learn about reading an ohm meter.

Drat, more stuff to learn! More shop time!

Thank you,
Daryl
MN

Daryl,

Here's what I know about this, the thermal is actually a wire wound resistor, they are rated by a chart from the heater manufacturer, if the amps get too high they heat up more than normal (hot!), and in the thermal disconnect there are various devices used to detect the heat and disconnect the power from the motor to protect it, (usually a bi-metal piece similar to a old car choke coil). So it has been my experience these thermals don't go bad very often, just like a wire wound resistor for it to fail, it would normally burn open and nothing would work!

Remember these heaters are matched to a exact, motor amp specs; IE Did anyone change the motor on this machine? and it is not the same amps, effiency, power factor? You said it just started doing this, so I assume you had it running before? Remember these thermals protect the motor from overload, is there anything mechanical going on here? Bearings, something binding etc. Remember the overload could be either be electrical or mechanical? Need to eliminate the mechanical just to be sure, if something happened to be too tight somewhere it may trip the thermal also.
Maybe I missed it, but I asked you once before what type of motor are we dealing with? With 2 thermals it sounds like a single phase motor? The three phase always have 3 heater’s in there, single phase, three phase of a static converter or?
 
Thanks Bob in Oregon
 
Daryl,

Here's what I know about this, the thermal is actually a wire wound resistor, they are rated by a chart from the heater manufacturer, if the amps get too high they heat up more than normal (hot!), and in the thermal disconnect there are various devices used to detect the heat and disconnect the power from the motor to protect it, (usually a bi-metal piece similar to a old car choke coil). So it has been my experience these thermals don't go bad very often, just like a wire wound resistor for it to fail, it would normally burn open and nothing would work!

Remember these heaters are matched to a exact, motor amp specs; IE Did anyone change the motor on this machine? and it is not the same amps, effiency, power factor? You said it just started doing this, so I assume you had it running before? Remember these thermals protect the motor from overload, is there anything mechanical going on here? Bearings, something binding etc. Remember the overload could be either be electrical or mechanical? Need to eliminate the mechanical just to be sure, if something happened to be too tight somewhere it may trip the thermal also.
Maybe I missed it, but I asked you once before what type of motor are we dealing with? With 2 thermals it sounds like a single phase motor? The three phase always have 3 heater’s in there, single phase, three phase of a static converter or?
 
Thanks Bob in Oregon

Sorry that I missed your the motor question. I believe it's the factory motor 10hp 3ph, I can't see the spec plate based on the tight fit under the headstock of this 5000lb 1936 Turret Lathe. I picked up a 20hp rotary converter. A couple days before I first noticed it was cutting out, I had a short in the factory switch which blew a circuit breaker in the main panel. It's now repaired. Could that have done it?
 
Sorry that I missed your the motor question. I believe it's the factory motor 10hp 3ph, I can't see the spec plate based on the tight fit under the headstock of this 5000lb 1936 Turret Lathe. I picked up a 20hp rotary converter. A couple days before I first noticed it was cutting out, I had a short in the factory switch which blew a circuit breaker in the main panel. It's now repaired. Could that have done it?

Daryl,

That's great glad you got a rotary converter! The static one for you saw, will probably be fine, due to the fact that it is a lot lighter use than a lathe. Tha converter cutting out could have been the problem, depending on what was going on with the rotary converter, these 3 phase motors do not running on 2 legs, so if your contactors etc get carbon built up on them, and it looses one leg, it will almost always blow the line fuses or trip thermals, especially on start up! Might want to lock the power out, and inspect and clean the contactor, I use some diamond files, and some electric cleaner. CAUTION: Make sure the electric motor fumes are totally aired out of the contactor box before you turn it on!! I Watched a guy due that once, without it aired out, on a huge metal roll, at my buddies shop, there was machine oil in there, and it caught fire and burnt up 60% of the wiring in the box, as soon as it turned on and the contactor sparked!
Bob in Oregon
 
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