Panasonic 3 phase driver running on 1 phase?

[gavztheouch]

Hi,

I have some panasonic servo drivers model number MSDA043A1A

I would like to wire them using a single phase supply, but from the model number I can tell these are meant for 3 phase supply. Panasonic tell me it is possible to use a single phase supply but will not tell me how to. I don't have the knowledge to work it out so I was interested to know if anyone has done this before and how do I go about it.

I am in the UK and I have a 230-240v single phase supply.

My servo has the connections L1, L2, L3 and ground.

Many thanks

Gav

Similar Threads:

• Newbie- 2 phase driver & 4 phase 6 wire stepper HELP!
• Newbie- ? about vm-16 or vm-17 running single phase?
• running off rotary phase converter
• Somewhat OT. running a three phase motor from DC?
• Running a VF-4 on a phase converter??

[keebler303]

If it is like most servo drives, the 3 phase is fed directly into a 3 phase bridge rectifier, where it gets turned into DC. If you simply connect your single phase to two of the wires, it should work fine. Some manufacturers recommend connecting one wire to L1 and the other wire to both L2 and L3. The paralleled paths lower losses a little bit so it will be a tad bit more efficient. Also on single phase you should reduce your max current a bit as single phase supply will have a much higher ripple voltage than three phase, with the same DC bus capacitance. I'd be surprised if the manual doesn't explain how to do it, most I have seen do.

Matt

[gavztheouch]

Thanks Matt thats great info.

How would I reduce the max current is this something I set within the drive (software)?

Cheers

Gav

[keebler303]

I'm not sure how familiar you are with electricity. The AC is a sine wave that gets rectified into dc. You need capacitors to store energy so that in between the peaks of the AC sine wave, you still have DC power. The larger the current is, the faster these capacitors will discharge between peaks of the sine wave. If the capacitors discharge too much, it could actually fault the drive due to undervoltage. This should not harm the drive but might spoil whatever you are working on at the time. I think the manufacturers recommend going up something like 50% on rated current if you plan to use single phase. Capacitors cost money so they only put in enough capacitance to keep everything in spec with 3 phase power. The higher current rated drive has more capacitance so it handles the single phase power better.

In reality I would say just use what you have and if you have no problems then smile. The drives I have used can monitor the DC bus voltage. If you can do this, you should be able to get a good idea of how you are doing.

To answer your question, you can probably set the current limit in the drive. If you set it too low, you will loose torque on your motor, which could make the position error exceed limits and fault the drive. If you set it too high, the motor can draw too much current, cause the DC bus voltage to sag, and fault the drive. So either way if you push it too hard, you will fault the drive.

What is the rated current of the motor and of the drive?

Matt

[mactec54]

gavztheouch

For main Power Supply only use L1 & L3 for single phase

You will have to wire the control power as well L1C & L2C

[Johns tool room]

so basically a 1 phase input should run a 10 amp motor with 15 amp rated driver?

[mactec54]

so basically a 1 phase input should run a 10 amp motor with 15 amp rated driver?

If the encoder plays niece that can work, if you have a phase lose alarm there is a way around that as well.

[servtech]

so basically a 1 phase input should run a 10 amp motor with 15 amp rated driver?

Possibly, but you need a big enough single phase supply and cable gauge size. The current draw may make the cable get hot or even fry supply wire insulation.

[Johns tool room]

Possibly, but you need a big enough single phase supply and cable gauge size. The current draw may make the cable get hot or even fry supply wire insulation.

3^.5 times bigger.

[Johns tool room]

If the encoder plays niece that can work, if you have a phase lose alarm there is a way around that as well.

what the relation between the encoder and power input to the driver? I'm not getting that. Please explain

[mactec54]

what the relation between the encoder and power input to the driver? I'm not getting that. Please explain

Some Servo Motor / Encoder has to recognize the drive they are being connected too, so if the motor size does not match the Servo Drive, they will not work, this is with most quality Servo Drives Motor combo, in your case it should work,

As for cable the size is related to the Amps being used only so if the max amps is 10A, the correct wire size would be rated at 12.5A this is what code would require.