Pm1440gt Ordered

Hi Everyone,
New guy here. After months of thought and staring at stuff online, I jumped in with both feet and ordered a PM1440GT to be my first lathe. I talked with Matt for a bit, and ordered it with a 3ph motor, and the Hitachi VFD. The lathe is currently expected in my driveway sometime around the 1st of Dec. I have already received the VFD.
Upon unboxing the VFD, and attempting to comprehend the instruction book, I read through JBolt's process with the same equipment. I have to admit that the gut & re-wire process has me a bit intimidated. I haven't done anything like this before. Household wiring, yes. Motor control systems, no. Still undecided as to whether I want to attempt the re-wire on my own, or hire it out. I'd like to do it myself, but I would definitely need some help interpreting the diagrams MKSJ provided & JBolt posted.
This forum is awesome, I'm spending an irresponsible amount of time here.

Don't forget to post pictures when your new toy arrives. We all want to see it.

Tom S.

New guy old guy no difference, I will bet if you want to tackle the wiring yourself if you ask for help you will get it. As to the irresponsible amount of time issue, well that will only get worse.

dpd,

If you are comfortable with household wiring you should have no problem taking this on. The wiring is not all that difficult once you get into it. I still don't fully understand how all the low volt relay wiring works I just followed the schematic from mksj. At some point I will look at the relay sheet to fully understand it. The rest is really straight forward.

You need to decide is if you want the extra options the VFD provides or just use the VFD for power. I think it is worth it to do the extras. I went a little over the top compared to what most do but that's just the way I am. It is certainly possible to do a minimal foot print install and keep the electronics in the factory location. The VFD would need to be mounted in or on the base or remotely on a wall.

Look at all the various configurations that mksj has done for the 1340gt. They are all very similar. The main difference with the 1440gt is keeping the mechanical brake that requires a new double pole switch to replace the factory single pole. The switch is used to send a power off and freewheel commands to the VFD so the electronic braking does not interfere with the mechanical brake.

Don't hesitate to ask for help. It's a fun process to go through and you will know your machine better in the end.

Given my current (low) level of experience, I believe I would like to keep the controls in the factory configuration. I'll use the mechanical braking function of the existing foot brake, and I'll need power for the factory coolant pump, factory light, and DRO.
Things may become somewhat clearer once the machine is sitting in front of me.

Forgot the tach. Definitely want a tachometer with the VFD.

A number of individuals using a VFD on the PM1340 and 1440 laths have disconnected the high voltage wiring going to the forward and reverse contactors, leaving all the other wiring intact. They then use one set of contacts on each contactor to connect the common/P24 of the VFD to the VFD input 1 for forward and input 2 for reverse. This will function just like the stock machine controls, you would add a speed pot. The motor is directly wired to the VFD. The tricky portion is how the coolant is connected. In some machines (1440GT) there are jumpers from the motor contactors to the coolant contactor, so the coolant needs to be directly wired to the switched mains voltage. As far as I am aware, the coolant pumps on the PM1340 and 1440 machines are single phase. Single phase power going to the machine is usually connected to L1 and L3, but can also be R and S (i.e. the two high voltage terminals that connect power to the system transformer. If you have a schematic or manual, I can provide some assistance in suggestions. Also some pictures of control system board when you get the machine.
Example on the PM1340GT which is very basic. http://www.hobby-machinist.com/thre...control-board-and-switches.49022/#post-413995

A complete system rebuild is doable, but you need to trace out all the wire connections to the different safety switches, these are usually serially wired with the E-Stop. You need to build a new control board and add relay logic controls. A bit more complicated if you want to do a complete control system such as Jbolt did, it takes some planning and understanding of wiring. I can provide you with recommended programming parameters for the WJ200 depending on the build approach you want to take. I do not recommend directly connecting the VFD to the spindle direction controls and bypassing the safety interlocks, there are some work arounds to make this work, but it represents a safety issue in my book.

On the tach, I would recommend a basic eBay Hall sensor tachs or the MachTach 1/2 half size (requires building), either can be mounted in a Hammond 1590B diecast box. I went with a MacTach, but I have done a number of subsequent builds using the eBay ones in a Hammond box, and they where accurate, worked well and are inexpensive. If you do not need the additional features of the MachTach, I recommend the eBay ones with a Hall sensor and a single magnet.
http://www.ebay.com/itm/Hammond-159...x-Diy-Motley-Mods-fast-shipping-/172377067384
http://www.ebay.com/itm/Digital-Red...all-Proximity-Switch-Sensor-NPN-/171385171075
http://www.machtach.com

The coolant pump is single phase and there is no wiring schematic in the manual.

I went with the ebay tach and it works fine.

Ordered the Ebay tach, and the Hammond box. Any suggestions for the pot?

I used this one. https://www.automationdirect.com/ad...icators/22mm_Metal/Potentiometers/ECX2300-10K