What's new
What's new

3ph POWERMATIC 1150 (How to wire vfd with mag starter)

Grnmtntri11

Plastic
Joined
Feb 16, 2020
How do I wire In a vfd (haven’t gotten it yet in the mail). I have single phase power in my shop.
It’s a 3 phase drill press Motor with the furnas magnetic starter. where do i put the VFD? Do i completely remove the mag starter and wire straight from my single Phase power to the vfd and then to the motor? Or put the vfd between the mag starter and motor?

If I keep The Mag starter where do i wire the incoming 220 power? do I bring Power into the starter and connect to the L2 L3? Neutral goes?

Thanks in advance
 
You'd use the contactor to power up the VFD. Nothing goes between the VFD and motor except cabling.

So, single phase power to the magnetic starter (does this change how the wiring is laid out inside the starter?)
Then single phase power leaving the starter to the VFD and then to the motor?

I guess I just need help with details. Where do the two input hot lines from my 220v attach into the starter? And where will the outgoing power to the VFD leave the starter? And is the starter setup for both 3phase and single phase?
 
Take the magnetic starter or contactor out of the equation. Have a machine disconnect at the machine. From that go to the VFD, then to the motor. Hook up a start stop button to the VFD. If the start stop button on the saw stays in the on or off position, use it, if not wire in a on-off toggle switch to the VFD.
 
The mag starter is mostly useless and undesirable but my above comment is predicated on your wanting to use it. If you do, you would need to run single phase into it, then run its output to the VFD. But, chances are your mag starter (if made in the last 20 years) will sense a current imbalance as it is missing a leg and will trip or otherwise be unhappy. There are ways to fool it...you can Google that.

Better would be to use a magnetic contactor (or an old-school throw switch) to power up the VFD. Once the VFD is running, you would then use the VFD controls to start/stop the motor. You never want to break the circuit between the VFD and motor. You also don't want to shut the VFD off when the motor is running. The VFD is first to be powered on and last to be powered off, in other words.

I just did my lathe. In the photo you can see the wall mounted VFD and below it is the box holding the magnetic contactor. The mag contactor allows me to power up the VFD remotely, i.e. from a switch. In my case, I am operating the VFD remotely by using the lathe's original Forward/Reverse switch.HL460 finished.jpg


The mag contactor, unlike a mag starter, is fine with you using only two of its three poles. I'd suggest looking on Ebay for one based on your amperage need. The one I used is a WEG brand, CWB series. Below is an example good ro 32 amps but I am guessing you need less than 32 amps? Note that these contactors have coils that can be triggered by DC or AC current in a variety of voltages so be sure to buy what you need. The 'D15' designation is what most people want - a 120 volt AC coil - but there are others as well.

WEG CWB32-11-30D15 Contactor | eBay
 
Thanks for the information Greg and others
I’ll most likely try and mount the vfd to my drill press and use it as the on/off switch and. It worry about a remote option.
 
I'm with removing any magnetic device (contactor, motor starter, mag switch) if you are going to a VFD.

Just for reasons of simplicity, if you kept the contactor to power up the VFD now you need 2 sets of controls, start/stop the VFD via an AC seal-circuit AND start/stop the spindle via control wiring to the VFD.

Depending on how the existing start/stop switches are setup (could be mechanically interlocked rocker switches or momentary contact versions which are independent). Once you figure out that you can choose 2-wire or 3-wire start-stop in your VFD and wire accordingly on the low voltage I/O terminal strip. Then you program the VFD via parameter selection.

THe power side is simple....L1, L2 to the VFDs input terminals and T1,T2, T3 to the motor. That part is a 10 minute job. The rest of it takes significantly more time but its all in the manual. You might have to read and re-read it 3-4 times to understand or post back here.
 
So while he's asking these questions and you guys are on the subject, what about heaters? Are those always taken out of the equation also since the VFDs have over-current protection? Do they need to be? What if one had a VFD sized large enough to accommodate all possible combinations of combined running amperage and LRA of all motors on a machine tool? Could the VFD output then be left in "Run" and the machine operated from its original controls? I've always wondered about this.
 
"I'm with removing any magnetic device (contactor, motor starter, mag switch) if you are going to a VFD.

Just for reasons of simplicity, if you kept the contactor to power up the VFD now you need 2 sets of controls, start/stop the VFD via an AC seal-circuit AND start/stop the spindle via control wiring to the VFD".


You're always gonna need to have two sets of controls when you use a VFD. That's because when you use a VFD, essentially, you are creating your own power source that is fed by the grid but otherwise separate from the grid. So you need a way to turn the spindle ON/OFF - the VFD provides this - and you need a way to turn the VFD itself ON/OFF.

So even if the VFD On/Off is only a knife switch, you have to have a way to make and break the power to it.

A contactor is simply an 'easier' way to do that if you are not physically near the VFD. It's the same reason we use light switches near the door instead of climbing a ladder and turning the light bulb on by screwing it in to the base.

The last thing you wanna do is leave the VFD powered up all the time.

A modern contactor also provides the most 'safe' way to start the VFD in terms of voltage surges. It reliably opens and closes the feed, and (in my case) I put some fast blow fuses in line as per the VFD maker's recommendation.

If you are suggesting the VFD be powered up and powered down with the same controls as the spindle (not sure if that's what you mean), that's also a no-no for a lot of reasons.
 
I don't see why one couldn't use this, after all its just a NC contact that can be wired in series with your Stop pushbutton in a classic 3-wire start/stop circuit to cause a controlled stop. You might not know why at first though, the spindle would just stop without other notice or alarm from the VFD. In some cases it might be tough to separate the overload section from the contactors, but most have screw terminals in there somewhere.

But you are correct, usually the VFD has overcurrent protection built into it, and its adjustable by programming a number into a parameter.
 
Your point is valid, Greg. It will definitely work as you described.

But getting some cross section of the populous, inexperienced with VFDs, to wire up another AC-based 3-wire start/stop in addition to reconfiguring the normal spindle start/stop for low voltage operation would = Mind Blown. :eek:

The 2 or 3 pole lockable disconnect (fused or not) would be as simple as the power side wiring on the VFD.
 
Do i completely remove the mag starter and wire straight from my single Phase power to the vfd and then to the motor?

Yes. Remove the starter and mount the VFD on the same plate, if it fits there.
Keep the starter for another day. I also had to make a choice about this and decided to use a manual breaker switch between the power lines and the VFD.

You can add remote controls to the front of the drill press like a foot pedal switch.

I'm using a foot pedal switch on a single phase motored drill press. If the motor was 3 phase I would still use a foot pedal switch.

Your VFD manual is probably available on the internet and you can read about it before the VFD arrives.

What VFD is it?
 
Doesnt look like my last response posted.

My VFD is made by KB electronics, its the hybrid drive 1 to 3 phase. If my VFD has an on/off switch built in, I can go straight from the power supply plug to my vfd, correct? I dont need an additional switch between supply power and VFD, that would seem redundant.

I also just ordered a foot pedal switch but for my portaband saw stand. I think if the vfd is mounted to the press it will be just as easier or easier to use that switch instead of foot pedal. What if you wanted to grab something from the table next to you and keep the press running?

My big questoin is" will it work fine to run power from the supply outlet to the VFD if the VFD has its own On/OFF switch, and then from the vfd to the motor.
 
Yes it is. In the picture on the link it’s in the back right
Had the turn dial, on off toggle switch and optional forward and reverse toggle switch.
 
What if you wanted to grab something from the table next to you and keep the press running?

My big questoin is" will it work fine to run power from the supply outlet to the VFD if the VFD has its own On/OFF switch, and then from the vfd to the motor.

Next time I'm drilling and want to grab my sprout sandwich from the table I will think about that ...

You answered your question if you already have a power switch. If your mounting plate is facing the front side of the drill press then you have almost no work to do.
 
HAHA

If I have an ON/OFF switch on the front of the drill press already, can I keep the VFD toggle switch in the ON position and use the original on/off switch from drill press. Power to the originl switch, then to the vfd, then motor.
Or is it recommended to shutoff power at the vfd each time.
 








 
Back
Top