# Is the GS1 series AC drive compatible with this three phase motor?

#### belae1ka

Joined Nov 20, 2016
16
My senior design adviser told me that the VFD must be the same brand as the motor that is being used, I'm not sure I believe this.

I plan on using a GS1 series AC drive, here is a link;

Here is a link to the motor;
https://www.mcmaster.com/#6136k671/=154ilst

What should I look for when looking for compatibility? HP, amps, single/three phase, input voltage?

Also, the amps at full load is rated at 0.8-0.8/0.4 Amps. I am confused with the formatting of this number, why is 0.8 divided by 0.4?

Thank you.

#### tcmtech

Joined Nov 4, 2013
2,867
You should be looking to make sure the VFD units output ratings are equal or higher than the motor power and amp ratings So if you have a 1/4 HP motor you need a VFD that rated for 1/4 or more HP motors.

As for the .8 divided by.4 your reading it wrong. In motor and power supply specs that means there are two ratings for two different operating voltages like .8 amps at 120 volts or .4 amps at 240 volts which on a nameplate would look like 120/240 VAC and .8/.4 Amps.

Joined Jul 18, 2013
28,759
Also, the amps at full load is rated at 0.8-0.8/0.4 Amps. I am confused with the formatting of this number, why is 0.8 divided by 0.4?
.
You will notice that is a dual voltage motor. 230/460v 3ph.
Hence the two current ratings.
It has to be a 3ph motor, for a 4 pole like that one, I usually go up to 120hz, if it is not a vector rated motor.
Using the 220v motor means you can run off of 1ph 240 residential supply if needed.
Max.

#### belae1ka

Joined Nov 20, 2016
16
You should be looking to make sure the VFD units output ratings are equal or higher than the motor power and amp ratings So if you have a 1/4 HP motor you need a VFD that rated for 1/4 or more HP motors.

As for the .8 divided by.4 your reading it wrong. In motor and power supply specs that means there are two ratings for two different operating voltages like .8 amps at 120 volts or .4 amps at 240 volts which on a nameplate would look like 120/240 VAC and .8/.4 Amps.
Thank you for the quick response. The motor is 208-230/460V AC. So does that mean that the full load amps is 0.8Amps for 208-230V AC and 0.4Amps for 460V AC? Also, does 208-230/460V AC mean that the motor can be wired to either 230V AC OR 460V AC?

Thank you.

Joined Jul 18, 2013
28,759
mean that the motor can be wired to either 230V AC OR 460V AC?

Thank you.
The VFD input voltage has to be compatible with the motor rated voltage you are using.
As already mentioned 240v 1ph can be used as a supply (3ph out), but there are very few 460v rated VFD's that can be used on 1ph, if any.
Max.

#### belae1ka

Joined Nov 20, 2016
16
You will notice that is a dual voltage motor. 230/460v 3ph.
Hence the two current ratings.
It has to be a 3ph motor, for a 4 pole like that one, I usually go up to 120hz, if it is not a vector rated motor.
Using the 220v motor means you can run off of 1ph 240 residential supply if needed.
Max.
When you mention 120hz are you talking about the VFD or the motor? The VFD's input voltage is rated at 50/60hz and the motor is rated at 60hz.

Also, how do I know if a motor is vector rated? There is not much detail included in the specs of this motor.

Thank you

#### belae1ka

Joined Nov 20, 2016
16
The VFD input voltage has to be compatible with the motor rated voltage you are using.
As already mentioned 240v 1ph can be used as a supply (3ph out), but there are very few 460v rated VFD's that can be used on 1ph, if any.
Max.
In the shop that the VFD will be powered, they have three phase power outlets. This should be fine as long as the VFD can take in a three phase input voltage right?

Joined Jul 18, 2013
28,759
Running a 4 pole motor at 120hz essentially doubles the rpm. Which I have found is no problem for non-vector rated motors, as the balance and bearings are usually rated the same as the 2 pole version.
Most VFD's under 5hp rating will operate on 240v 1ph.
If you have 3ph available the restriction does not apply.
But if the 3ph outlets are 460v however, you will need a 460v input rated VFD.
Max.

#### belae1ka

Joined Nov 20, 2016
16
Running a 4 pole motor at 120hz essentially doubles the rpm. Which I have found is no problem for non-vector rated motors, as the balance and bearings are usually rated the same as the 2 pole version.
Most VFD's under 5hp rating will operate on 240v 1ph.
If you have 3ph available the restriction does not apply.
But if the 3ph outlets are 460v however, you will need a 460v input rated VFD.
Max.

One last important question for ya if you would be so kind. The shops outlets are 250V, 50Amp. I am confused now on how this would work considering the VFD is 230V/460V AC. Does this mean that I have to find a different VFD? Or does this simply mean that the VFD will work considering that the shop outlet is able to provide the 230V? In other words, is the shops outlet too much voltage? would I need to step down the 250V voltage?

Joined Jul 18, 2013
28,759
I would not see 250vac a real problem, the input to the VFD is usually a Bridge rectifier and a capacitor bank, and I would not suspect that the components would be that tightly rated.
Generally current is the main issue to watch in a VFD.
Is this 3ph 250v as that is an usual value, what country of origin are you?
Those GS1 you mentioned are 230/120v not 460v.
Max.

#### belae1ka

Joined Nov 20, 2016
16
I would not see 250vac a real problem, the input to the VFD is usually a Bridge rectifier and a capacitor bank, and I would not suspect that the components would be that tightly rated.
Generally current is the main issue to watch in a VFD.
Is this 3ph 250v as that is an usual value, what country of origin are you?
Those GS1 you mentioned are 230/120v not 460v.
Max.
I am from the USA, I have decided to go with a DURApulse GS3 series AC drive. Considering current is the main issue to watch out for I am going to plan on buying fuses for the VFD.