Which Spindle and VFD... again

[mactec54]

Just for clarity of the products that I have and for my sanity... I have 220v at my home and I'm using both a 220v VFD and 220v spindle so nothing I have will be 3 phase unless the VFD is converting to 3 phase which I don't believe is the case.

Given that information, if my spindle is 15amp and should draw no more than 1.5 it's amperage (thanks Al) then doesn't that work out to (15*1.5 = 22.5amp max) ?

You should read more carefully AL's post is incorrect for your Single Phase there is a big difference between using 3 phase power and Single Phase power supply

Your Power supply is 240v Single Phase for NA not 220v

Your VFD Drive is using 240v Single Phase Power input and 220v 3 Phase Power output All VFD Drives output 3 Phase power to the 3 Phase AC motor they are driving

Just look at the VFD Drive spec's you posted it tells you what the input and output Amps are for Single Phase

[adam_m]

You should read more carefully AL's post is incorrect for your Single Phase there is a big difference between using 3 phase power and Single Phase power supply

Your Power supply is 240v Single Phase for NA not 220v

Your VFD Drive is using 240v Single Phase Power input and 220v 3 Phase Power output All VFD Drives output 3 Phase power to the 3 Phase AC motor they are driving

Just look at the VFD Drive spec's you posted it tells you what the input and output Amps are for Single Phase

OK, thanks for clearing that up - the VFD is converting 240v to 3 phase...

So, back to my original question(s)... since the motor is 3 phase 15amp I think the calculation was correct (15*1.5 = 22.5amp max)?

[ger21]

That's output current, not input.

If you look at your manual, it shows a 2.2Kw VFD with 10 amp spindle requires 23 amps on the input side. Since your spindle is 15 amps, than it would need 1.5 * 23. or 34.5 amps. With the other size VFD's, the input current is roughly double the output. So somewhere between 30-35 amps.
So you would want between 1.2x and 1.5x the 30-35 amps. A 40 amp filter would probably be fine.

[adam_m]

That's output current, not input.

If you look at your manual, it shows a 2.2Kw VFD with 10 amp spindle requires 23 amps on the input side. Since your spindle is 15 amps, than it would need 1.5 * 23. or 34.5 amps. With the other size VFD's, the input current is roughly double the output. So somewhere between 30-35 amps.
So you would want between 1.2x and 1.5x the 30-35 amps. A 40 amp filter would probably be fine.

Thanks Gerry for that, I think I understand your math.

Of the 4 VFD units in the 220v section does the rated power column depend on the motor it's driving not the potential of the VFD?



So, if a GT-4R0G-2 unit were driving a 1.5KW spindle the rated input would be 14.2a and would require something like 1.5*14.2 = 30a breaker on the input side of the VFD?

I picked up a 25amp relay to use for powering the VFD via my G540 and now I'm thinking that's not going to be large enough based on this discussion.

[ger21]

"Rated Power" would be the max for the VFD, but yes, the actual power consumed would depend on the motor used.

When you say "power the G540", do you mean the stepper motor power supply?

But yes, it looks like your VFD could potentially draw 30 amps or more, so you'd probably want a 40 amp relay.

Personally, i prefer to just have the VFD powered directly, and turn on and off with the main disconnect.

[adam_m]

"Rated Power" would be the max for the VFD, but yes, the actual power consumed would depend on the motor used.

When you say "power the G540", do you mean the stepper motor power supply?

But yes, it looks like your VFD could potentially draw 30 amps or more, so you'd probably want a 40 amp relay.

Personally, i prefer to just have the VFD powered directly, and turn on and off with the main disconnect.

OK, so I'm on board with the math then thanks for clarifying.

I was attempting to use pin 5,6 on the G540 to remote turn on the VFD... the main reason behind that is that the VFD when plugged in is always on. If the VFD actually had an on/off switch it would be a non-issue...

The only other on/off would be at the breaker box which is highly inconvenient or to plug/unplug the unit from the wall plate.

[Al_The_Man]

If the VFD actually had an on/off switch it would be a non-issue...

The only other on/off would be at the breaker box which is highly inconvenient or to plug/unplug the unit from the wall plate.

It is customary to fit a contactor on the input side just for E-stop reasons or at power up/shut down, this conforms to NEC/CEC which I have always had to do due to only doing industrial installations.
Also recommended by most VFD manuf.
Al.

[mactec54]

Thanks Gerry for that, I think I understand your math.

Of the 4 VFD units in the 220v section does the rated power column depend on the motor it's driving not the potential of the VFD?



So, if a GT-4R0G-2 unit were driving a 1.5KW spindle the rated input would be 14.2a and would require something like 1.5*14.2 = 30a breaker on the input side of the VFD?

No you are getting confused again with where the numbers come from, you would need a max of 20A breaker and only because a 15A breaker would be border line for a 1.5Kw spindle motor

I picked up a 25amp relay to use for powering the VFD via my G540 and now I'm thinking that's not going to be large enough based on this discussion.

25A Way to low a rating I guess I just waste my time posting I said you would need a 40A solid state relay, and this would be the minimum in this case a larger Amp rating the better even 60A would not be out of place when using a solid state relay

[adam_m]

Yes, the SSR was a mistake on my behalf... I'm assuming a relay installation is figured differently than a breaker hence the need for a 60amp and not a 40amp?

So I think I've been educated and should choose a 60amp relay (if using) and a 40amp breaker on the input side which incidentally matches the breaker at the mains, and 40amp EMI filter.

I might just eliminate the relay altogether and just go with a disconnect switch as Mactec54 suggested.

[ericks]

I have a relay for e/stop for my VFD....it's 30A and it will be no problem(1.5Kw spindle). The circuit breaker is rated to protect my drive not my motor, the settings on the drive when done correctly will protect the motor. I won't ever use a ssr to "supply" drive power...
Usually i go one size up in drive Kw re motor size, just in case i decide to upgrade the motor later.

[Al_The_Man]

. I won't ever use a ssr to "supply" drive power...
.

Heartily Agree!
Al.

[adam_m]

Can I ask a quick question about the disconnect switch.... if purchasing a 40amp switch what would happen if there was a short in the circuit?

Does the switch have a reset/breaker function or would that be handled at he main panel 40amp breaker? is that the difference between a fused and non-fused type switch?

[mactec54]

Can I ask a quick question about the disconnect switch.... if purchasing a 40amp switch what would happen if there was a short in the circuit?

Does the switch have a reset/breaker function or would that be handled at he main panel 40amp breaker? is that the difference between a fused and non-fused type switch?

The main panel Breaker would be your only protection, the disconnect is just an On/Off switch, ideal you would have a breaker in your cabinet for each item that is connected to the main input supply power

[mactec54]

I have a relay for e/stop for my VFD....it's 30A and it will be no problem(1.5Kw spindle). The circuit breaker is rated to protect my drive not my motor, the settings on the drive when done correctly will protect the motor. I won't ever use a ssr to "supply" drive power...
Usually i go one size up in drive Kw re motor size, just in case i decide to upgrade the motor later.

He don't have a 1.5Kw spindle he is using a 3.5Kw spindle

[Al_The_Man]

Can I ask a quick question about the disconnect switch.... if purchasing a 40amp switch what would happen if there was a short in the circuit?

Does the switch have a reset/breaker function or would that be handled at he main panel 40amp breaker? is that the difference between a fused and non-fused type switch?

The choices are a main disconnect, (non-fused switch) which is just that, a switch, and must be used in conjunction with a fuse block or NFB
A Fused disconnect that has both, there is also a stand-alone NFB (non-fused breaker), which trips in the event of an overload, you can also get a NFB that has a remote shut off feature that has an activating coil for E-stop circuit etc.
Al.