Another PM1340GT Lathe VFD Control System Build with a Twist

[ptrotter]

Thanks Jay. I found that McMaster has what I need. I have ordered from them numerous times but didn't think about them for wire.

Paul

 

[Kiwi Canuck]

Mark, I am about to embark on a VFD installation on my new PM 1340GT and PM 935TS Mill, both ordered with 3 phase motors.

I have single phase available and I converted a dryer plug that was to be for a Welder to a sub panel and installed (2) 30 Amp breakers, fed from a 40 Amp breaker in the main panel on 4C 6AWG Alum wire.

I will run 4C (3 plus Ground) 10AWG copper in conduit to each VFD Enclosure Cabinet, I'll have one 120VAC circuit at each machine for DRO and what ever else I might need.

I have read most of your threads on here about VFD installs relating to the PM 1340GT and mostly understand the wiring concepts and can follow the schematics so I'm about 90% comfortable with tackling this on my own.

Before I jump right in to the deep end I wanted to ask a question that I was asked but didn't know the answer to, why can't I just install the VFD and hook the power cable up that came with the lathe to the VFD output and call it done?

I'm thinking about doing a similar setup to what you have outlined here, I will add the proximity stop and an air assisted coolant system later, but I want to plan for them.

I need a little guidance on what can be salvaged from the existing setup on the lathe, my setup looks a little different than some I've seen on here. (Probably to do with the CSA requirements for Canada)

I've ordered a few parts from Automation Direct to get started but now that I checked what I have, it looks like I could use or re-purpose some of these parts.

Here are a few photos,

I have ordered the following and received it already (or it's at the border awaiting pickup)
(1) Hitachi WJ200-015 from QMT
(1) Hitachi WJ200-022 from QMT
(2) Wiegmann 12"x 14" x 8" hinged cabinets from Amazon
(2) Weigmann Back Plates
(1) Breaking resistor 500 Watt 50 ohms, ebay
(1) Breaking resistor 500 Watt 35 ohms, ebay

The rest from Automation Direct and is on the way.
(1) ECX1510 Joystick Selector Switch 2-position, momentary, 2 N.O. contact(s)
(1) GCX1320-22 Selector Switch 3-position, maintained, 2 N.C./2 N.O. cont
(2) ECX2300-5K Potentiometer 5K
(2) ECX2640 Legend Plate for Potentiometer.
(1) GCX1226-24L Twist-to-release, LED illuminated, 1 N.C. contact.
(1) AD-ASMM-24 MOV pack
(1) AD-BSMD-250 Diodes pack.
(1) 783-3C-24D Relay 3 Pole 24VDC
(1) 783-3C-SKT Base for 3 Pole Relay
(1) 782-2C-24D Relay 2 Pole 24VDC
(1) 782-2C-SKT Base for 2 Pole Relay

I figure I'm still missing a bit of stuff to complete the job but thought I better check in with you for some guidance before I move on.

Edit, I also have
(2) Tachometers ebay China
(1) Easson ES-8A 2 Axis DRO
(1) Easson ES-8A 3 Axis DRO

Thanks in advance,

David

 

[mksj]

Hi David,
I would send me a PM with your email so I can help you in more detail. You cannot connect the VFD directly to the input power of your machine, the output of the VFDs must remain connected directly to the motor and should not have contactors between the motor and the VFD, nor any other control systems. Also the transformer would not operate correctly along with a number of other controls. There is a previous post on VFD enclosures and recommended setup in the Precision-Matthews machine forum.

The control box and HV wiring is different in your machine then what I have previously seen, as the 1340GT models I have seen do not have fusing nor a power disconnect switch. So I am not sure if yours is a regional requirement and the 1340GT is a special order, or this is a new machine build configuration. Up front to get things rolling I suggest you do a basic VFD install on the 1340GT and use the contactors to switch VFD inputs for F/R, then delve into a complete control system replacement. When you get ready to do a full build, I would retain the stock control board, stock power disconnect and the fuse holder. Power would come to the disconnect switch on the machine and then too you VFD enclosure. On the control board you would remove the stock transformer, contactors and relay and add a DIN rail. If you retain the stock fuse holder then the 24VDC power supply would nee to be moved to the VFD enclosure or visa versa. You will need a total of 3 two pole relays for the 4 relay control system design, see attached file. A proximity sensor can be added at a later date, the coolant relay can either be wired for 24VDC for a air solenoid or 240VAC for single phase coolant pump. On the mill I have been recommending a 3 wire VFD control which is very easy to implement.
Mark

 

[Kiwi Canuck]

Thanks for the schematics Mark, absolutely top notch.

I printed out the lathe schematics and studied them previously but had not seen the ones for the mill which looks like a breeze compared to the lathe, I think I'll tackle that one first.

PM sent.

David.

 

[wrmiller]

Thanks for the schematics Mark, absolutely top notch.

I printed out the lathe schematics and studied them previously but had not seen the ones for the mill which looks like a breeze compared to the lathe, I think I'll tackle that one first.

PM sent.

David.

I had never done a VFD install, and did the lathe first. You're right, the mill is much easier...

 

[Ramblerman68]

Hey all, just a quick note and testament to Marks impressive engineering and great workmanship. The assembly, soldering and general fabrication of his 1340gt VFD "kit" is spectacular. Very well thought out instructions helped me and a much-smarter-with-electrical buddy get it all done in a matter of hours and not days. All this adds up to a very nice machine being that much more flexible and potentially useful. My goal was to not have to call Mark for "tech support" and we succeeded. Not a testament to my or my buddies abilities, but an attestation to the quality of Marks work. Truly impressive stuff and a big thanks to Mark for a great system!

SF,

Kevin

 

[Kamloopsendo]

Hi David,
I would send me a PM with your email so I can help you in more detail. You cannot connect the VFD directly to the input power of your machine, the output of the VFDs must remain connected directly to the motor and should not have contactors between the motor and the VFD, nor any other control systems. Also the transformer would not operate correctly along with a number of other controls. There is a previous post on VFD enclosures and recommended setup in the Precision-Matthews machine forum.

The control box and HV wiring is different in your machine then what I have previously seen, as the 1340GT models I have seen do not have fusing nor a power disconnect switch. So I am not sure if yours is a regional requirement and the 1340GT is a special order, or this is a new machine build configuration. Up front to get things rolling I suggest you do a basic VFD install on the 1340GT and use the contactors to switch VFD inputs for F/R, then delve into a complete control system replacement. When you get ready to do a full build, I would retain the stock control board, stock power disconnect and the fuse holder. Power would come to the disconnect switch on the machine and then too you VFD enclosure. On the control board you would remove the stock transformer, contactors and relay and add a DIN rail. If you retain the stock fuse holder then the 24VDC power supply would nee to be moved to the VFD enclosure or visa versa. You will need a total of 3 two pole relays for the 4 relay control system design, see attached file. A proximity sensor can be added at a later date, the coolant relay can either be wired for 24VDC for a air solenoid or 240VAC for single phase coolant pump. On the mill I have been recommending a 3 wire VFD control which is very easy to implement.
Mark

Thanks from me too Mark: I'm using you wiring diagram (I hope correctly) to plan the install of the VFD on the 935 I just ordered from Matt. Does look a bit simpler than the lathe!
alex

 

[wildo]

mksj- thanks for all the posts on this forum about VFD conversion. Can you please let me know what this device is with the arrow pointing to it? And I think the two long black bars on the grey holders is the fuse holders, right? Thanks!

 

[mksj]

Older system vertically mounted 24VDC to 12 VDC step down converter needed to run tach and other 12V lighting (stock LED lamp is 24V AC or DC). That is an older style board where the power supply was in the control box, newer versions I moved the power supply to the VFD enclosure, but the step down converter is still in the control cabinet. It is rated for 55W maximum. The fuse holders were for the power supply when placed in the control box, I now use a 15A dual breaker (power supply is 230VAC input) in the VFD enclosure.

Current systems w/o the power supply mounted on the control board, I use the step down converter in the lower right, also plug/socket connections for the front controls and P-sensor.

 

[Kiwi Canuck]

If you need one of those 24VDC to 12VDC step down converters, here they are.

https://www.amazon.com/Daygreen-Converter-Voltage-Regulator-Reducer/dp/B07JJ21GKP

Edit, here is the 5 amp model.
https://www.amazon.com/Daygreen-Converter-Voltage-Regulator-Reducer/dp/B07HFTSWB8?th=1
We use them at work by the dozen and they work well, never had a failure.

David.