Thread: VFD install summaries

Just a short note to say the two Powtran VFDs I ordered on the 8th (see previous post) and shipped on the 11th arrived in Perth on the 20th so 9 days in total and 4 of those days were road transport from Sydney to Perth. If you live on the east coast of Oz I would expect them to be a bit quicker than this. Either way the two small PI160 VFDs cost me a total of $24 for delivery which I cannot complain about.

So similar to Steve Manos I recently purchased a compressor pump and 3 Phase motor cheaply.
The motor specs say 5HP, 415v, 1420RPM, 7.0A delta wired
Picture 1.jpg
On removing the terminal plate cover the motor is already, like the spec says, delta wired
100_1392.jpg

Under the cover though it appears that it can be wired in either delta or Y
100_1393.jpg

Does this mean that this motor once changed to run in Y can be used with a VFD? I presume that internal mods to the motor would be necessary - not just changing the jumpers.

Stewie

No, unfortunately, Stewie. It is 415 Delta. You need a motor that runs on 240 Delta as the VFD puts out 240V 3 phase.

Originally Posted by Stewie D

Does this mean that this motor once changed to run in Y can be used with a VFD? I presume that internal mods to the motor would be necessary - not just changing the jumpers.

I assume you wish to run it on 240V VFD that makes 240V 3P

If so you have it the wrong way around, It's a 415V 3P, wired in Y, that can usually be reconfigured to run as a ∆ (whether its inside or outside the motor is immaterial) Whereby it will run at full power on 240V 3P.

A 415V 3P, wired in ∆, can be configured to run in Y but then to develop fun power you beed to apply 690V 3P

So basically you are stuffed with that motor if you want to run it from a 240V 3P VFD.

I know this because I got caught out in the same way. You can leave it wired as a 415V 3P delta and it might even work but it won't work for long. Mine was a 4H motor and it worked for about 3 months before it cooked the motor. In the end I swapped it out for a 240V SP motor since you don't need speed control for a compressor.

Full power development is essential for a compressor since it works at close to full power during most of the charge cycle.

Bummer.
So if I found a 5HP 3Phase 415 wired in Y motor that can be changed to delta but at 240v, from what you are saying you would still get the full 5HP?
Sorry if my questions are pretty basic. I am but a humble carpenter...

Stewie

Originally Posted by Stewie D

Bummer.
So if I found a 5HP 3Phase 415 wired in Y motor that can be changed to delta but at 240v, from what you are saying you would still get the full 5HP?

Yep - make sure you match the RPMs as well.

This install is for 2 VFDs on a small Hercus metal working mill.
One VFD (Powtran 2HP PI160) controls the spindle and a PI130 (0.4kW, still waiting for it to arrive) will control the coolant/lube pump.

This is what the controls looked like when it arrived at my place
0.5 HP Y connected motor, with 3P electrical switching inside the lower cabinet behind the side door/panel.
Motor was convertible to ∆ in the motor connection box.
The coolant pump and reservoir are underneath behind the back door.
Sidebefore.jpg

Step one was to gut the electrical and fit a retractable shelf on drawer runners.
The two VFDs sit side by side on the shelf.
A 240V 92 mm fan has been added to vent the chamber - probably not needed but better safe than sorry as its kind of crowded in there.
FIlter was added to minimise dust ingress
dooropen.jpg EDoor2.jpg

The shelf can come right out to service the VFDs
drawerout.jpg

In addition the VFDs are on easily removable brackets so the can be laid down on their backs for easier wiring etc.
The spare bracket is where the PI130 for the 3P coolant pump will be mounted
VFDdown.jpg

Remote control of the VFDs is in teh process fo being move to a control panel on the Left hand side of the mill
Al bar mast "M" was fitted to lift the machine light up out of teh way.
Box B is a die case Al box I found in a skip and repurposed for this machine
SideHercus.jpg

Below shows the connections and as you can see it's pretty busy in there.
S1 powers up the VFDs and acts as a generalE-switch
S2 switches a light attached to the Mill on/off - it works even when the VFDs are off - ie during setting up etc.
10 way ribbon cable is for remote mounting of the VFD displays.
Blue ethernet (Cat 5) cabe is for pump control
Great Cat 6 cable is for spindle control

Panelguts.jpg

S on/off switches the spindle FWD/Off/Rev
P on/off power the coolant pump
F/C are the fine and coarse speed adjustments of the spindle.
The pump speed won't need to be changed all that often and when required will be performed via its own VFD display panel knob
Panel.jpg

When I first connected it up the VFDs fired up (beeped and fan ran) but there was no sign of life on teh display.
It took me some time to realize that the ribbon cables required a cross over cable somewhere in their path.
XoverCable.jpg

Its still not finished but it has been a fun project to shoehorn everything into the constrained spaces.

They're breeding.

vfds.jpg

Are those drives for upcoming projects?

Originally Posted by ericks2

Are those drives for upcoming projects?

The 0.4kW Powtran is for the coolant lube pump on my metal mill.

I am systematically replacing some of the 2HP HYs with equivalent Powtrans and I will be selling some 2HP HYs.

Just reporting I have completed the twin VFD install on the mill.
TwinVFDs.jpg

The VFD on the left is 2HP VFD for the motor and the slightly smaller one on the right is a 1/2HP VFD for the coolant lube pump.
It looks messy and it is, but that's the benefit of having the an electrical cabinet allows for all the cables to be tucked safely away.
tuckedawayVFDs.jpg

The coolant/lub pump motor is only 1/20th of a HP and was initially connected as a 415V Y.
The motor ran fine as is connected to a 240V VFD but it could only lift the coolant/lube to the required height at 45 Hz and flow was not much better at 50Hz.
IMG_3169.jpg
Running the pump at higher frequencies did not increase the flow suggesting the motor and pump impeller was right at the edge of its limit

Following conversion to ∆ this is now the flow rate at 60Hz and it will run at 70Hz.
Some details of the conversion of this motor to ∆ are sown here Tricky Y common point excavation
60Hz.jpg

I would have been ~$20 cheaper to purchase a new 240V singe phase coolant lube pump than a VFD, but the smallest pump and motor assembly would have been too large to fit into the space provided under the mill and it then would have meant locating the coolant tank and pump outside the mill.
An even cheaper alternative would be to use a 12 or 24V $50 water feature pump but most of these use magnets which can clog internally without significant filtration.

I like the possibility of controlling the flow with the pump speed - yes I know this can also be done with the small brass tap already on the mill. I will use that tap as the coarse control and the pump speed as the fine control.

Originally Posted by BobL

the benefit of having the an electrical cabinet allows for all the cables to be tucked safely away.

I think you mean 'hidden from view'
Nice work Bob. I like the slide out gear tray. Looks like a nice little mill too.

Originally Posted by NCArcher

I think you mean 'hidden from view'

Sure - on the weekend my BIL and nephew came over and I had the door open and slide out tray out. The nephew was magical attracted to all the coloured wires etc and even though I had the power off I didn't want him messing with any of it.

Nice work Bob. I like the slide out gear tray. Looks like a nice little mill too.

Thanks. Yes I can see a lot of fun, some heartache ,and lots of $ on tooling and accessories being spent.

I'd love to see any pics of remote panels that anyone has built for a mill - speed, direction, jog, etc.

Thanks!

Russ