Waiting on its arrival. Have been digging through the forums trying to get ideas for how to outfit it. I definitely want to use a VFD. I have seen alot of people use the Hitachi WJ200-022SF. Have also seen some people using the Teco 510. From what I understand the Teco cannot use a braking resistor but otherwise Im not clear on other differences--any suggestions? Id like to use an external pot speed control, forward/reverse/stop and a lighted E stop button. Are instructions for wiring these in the VFD manual? If not any suggestions for resources? Does the VFD need to have its own dedicated breaker? Thanks for any advice
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Soon to be PM 935 TS owner--Looking for advice
- Thread starter weejax
- Start date
Thanks, ill check it out
I used the WJ-200, as back then mksj was knowledgeable about it's workings and setup. Simple setup with a small box containing a fwd/off/rev switch, a pot for speed, and a e-stop mounted where the factory switch was mounted.
I didn't use a braking resistor and had the vfd braking disabled so I could just reach up and use the manual brake. It was a good setup.
I didn't use a braking resistor and had the vfd braking disabled so I could just reach up and use the manual brake. It was a good setup.
Hi @weejax
Several comments. You did not say which machine you purchased. There are 4 possible models and several possible additions you can add on.
I have the Hitachi WJ200-022SF in my PM1440GT lathe conversion. I am quite happy with it. You can down load my lathe conversion document and get a quick sense of how the WJ200 works. On the other hand the Hitachi manual is so complete its length is overwhelming.
Unless you purchased the 3PH motor and do not have 3PH power to run it do not bother with the VFD. If you purchased the 3 phase version but only have single phase power at your place you cannot run your motor without one. If you have purchased the single phase motor then you cannot use these VFDs.
You may find you do not need variable speed anyway. After all you have 8 step pull going from 80 to 2720RPM. That is plenty for most any work. Get to know your machine. Check it out and make sure it operates well. Check the alignments(important). Check the backlash (important). Make sure you have oils (way oil and cutting oil and later gear oil). On the other hand if you did purchase the 3PH and do not have 3PH power you will have to a phase converter or VFD just to check out the machine.
I purchased PM940M-CNC-VS when they were sold (not as large or as nice as your machine but was all that I could get into my shop room.). (3 Phase, 1.5KW motor). It looks/configures somewhat different from what PM calls a PM940M today. It has a Delta model VFD015E21AVFD and it works fine. It is a 2.2KW model. A little cheaper than the Hitachi. About all you do with a VFD on a mill is change the speed . To change directions you interchange a pair of the leads to the motor so the VFD effectively does this for you via the control inputs. Why would you need a braking resistor. Most VFDs have some what of a braking capability built in and an external breaking resistor is not really needed. It is not like a lathe where there can be a huge mass on the spindle so that there is a huge momentum that has to be stopped. Most of the momentum is due to the motor on the mill. (See my comments about the braking resistors in the write up listed above. It is impossible for me to see why one needs a several hundred watt braking resistor for a hobby machine. So why add this big bulky thing to your electronics?!)
"Id like to use an external pot speed control, forward/reverse/stop and a lighted E stop button." These are standard for most any VFD and wiring. Again see my write up for the general picture. The pot value is determined by the input parametes of the VFD. Typically a couple of KOhms. 3 to 5 turns pot is plenty. Anymore and it becomes a pain. A single turn pot might be a little hard to adjust if you want really fine resolution in speed.
"Does the VFD need to have its own dedicated breaker?" Probably, but it always depends upon what you have for wiring already. The Hitachi WJ200-022S converts from 220 single phase to 220 three phase to run the motor. I think I ran 10 gauge wire to the VFD and 12 gauge from the VFD to the 3HP motor.
"Have been digging through the forums trying to get ideas for how to outfit it." What did you order with the machine? You will need a vise. A varitiy of cutting tools, A DRO is really nice to have and if you have the money why not have PM install it. In fact if you do not have measurment instruments (vernier calipers, micromenters, dial gage, etc.) you will need them. I like these for the dial gauges and Clockwise has other gauges as well.
If you do not have any thing coming with the mill and do not have them you should at least buy a set of end mills from PM. Of course you will need a way to hold them, such as a chuck or collets. And you will need a way to hold your work down, vise and/or clamps. There is a list at the PM site of accessories for the mill. At least you know they fit.... I have the big swivel vise and it is nice, but heavy. As I have aged I can not just barely lift it (~95#) on to the machine table.
Lots of folks seem to add power feed to their machines.
Good luck.
Dave L.
Several comments. You did not say which machine you purchased. There are 4 possible models and several possible additions you can add on.
I have the Hitachi WJ200-022SF in my PM1440GT lathe conversion. I am quite happy with it. You can down load my lathe conversion document and get a quick sense of how the WJ200 works. On the other hand the Hitachi manual is so complete its length is overwhelming.
I posted several attachments and photos. Look at the pdf attachment "...Part 2 VFDDescription..." https://www.hobby-machinist.com/att...-vfddescript-links-dnl-l910_1440b-pdf.378083/
Unless you purchased the 3PH motor and do not have 3PH power to run it do not bother with the VFD. If you purchased the 3 phase version but only have single phase power at your place you cannot run your motor without one. If you have purchased the single phase motor then you cannot use these VFDs.
You may find you do not need variable speed anyway. After all you have 8 step pull going from 80 to 2720RPM. That is plenty for most any work. Get to know your machine. Check it out and make sure it operates well. Check the alignments(important). Check the backlash (important). Make sure you have oils (way oil and cutting oil and later gear oil). On the other hand if you did purchase the 3PH and do not have 3PH power you will have to a phase converter or VFD just to check out the machine.
I purchased PM940M-CNC-VS when they were sold (not as large or as nice as your machine but was all that I could get into my shop room.). (3 Phase, 1.5KW motor). It looks/configures somewhat different from what PM calls a PM940M today. It has a Delta model VFD015E21AVFD and it works fine. It is a 2.2KW model. A little cheaper than the Hitachi. About all you do with a VFD on a mill is change the speed . To change directions you interchange a pair of the leads to the motor so the VFD effectively does this for you via the control inputs. Why would you need a braking resistor. Most VFDs have some what of a braking capability built in and an external breaking resistor is not really needed. It is not like a lathe where there can be a huge mass on the spindle so that there is a huge momentum that has to be stopped. Most of the momentum is due to the motor on the mill. (See my comments about the braking resistors in the write up listed above. It is impossible for me to see why one needs a several hundred watt braking resistor for a hobby machine. So why add this big bulky thing to your electronics?!)
"Id like to use an external pot speed control, forward/reverse/stop and a lighted E stop button." These are standard for most any VFD and wiring. Again see my write up for the general picture. The pot value is determined by the input parametes of the VFD. Typically a couple of KOhms. 3 to 5 turns pot is plenty. Anymore and it becomes a pain. A single turn pot might be a little hard to adjust if you want really fine resolution in speed.
"Does the VFD need to have its own dedicated breaker?" Probably, but it always depends upon what you have for wiring already. The Hitachi WJ200-022S converts from 220 single phase to 220 three phase to run the motor. I think I ran 10 gauge wire to the VFD and 12 gauge from the VFD to the 3HP motor.
"Have been digging through the forums trying to get ideas for how to outfit it." What did you order with the machine? You will need a vise. A varitiy of cutting tools, A DRO is really nice to have and if you have the money why not have PM install it. In fact if you do not have measurment instruments (vernier calipers, micromenters, dial gage, etc.) you will need them. I like these for the dial gauges and Clockwise has other gauges as well.
If you do not have any thing coming with the mill and do not have them you should at least buy a set of end mills from PM. Of course you will need a way to hold them, such as a chuck or collets. And you will need a way to hold your work down, vise and/or clamps. There is a list at the PM site of accessories for the mill. At least you know they fit.... I have the big swivel vise and it is nice, but heavy. As I have aged I can not just barely lift it (~95#) on to the machine table.
Lots of folks seem to add power feed to their machines.
Good luck.
Dave L.
Did you buy it 3 phase? Just checking the basics.
Yep, 3 phase
Thanks for the very thorough comments and the pdf. The electronics schematics are beyond my abilities to make good sense of, but Im trying to learn. I only ordered the machine. will prob swap some of the DRO components from my RF-30 clone. as far why I need a braking resistor--I dunno, i saw alot of people on this board put one on. and they are like 18 bucks. but good to know its really not that necessary. thanks for the advice.
I don’t have the PM935, so can’t help you with particulars with that mill, but I use a Teco L510 on my mill, that one does not have provisions for a braking resistor, but the E510 does. If you look in the Teco manual, they have a page that shows how to wire the VFD, but it is a general arrangement and you may need to do things differently depending on what you want to do. That is on page 3-18 of the E510 manual. I wired mine with the three wire method, that uses a momentary push button for starting and stopping, that is shown on page 7-3. The three wire method is the preferred way to operate these since if you get a trip or power failure, it will not restart when power is restored like with constant contact switches.
I use coast to stop on my mill, doesn’t really need a braking resistor, but some people feel that is safer. It works just fine either way. Mine has a brake lever in case I want to stop quickly, I do that with the larger diameter cutters, but end mills only take a few seconds to stop.
I made a pendant that is wired into the VFD. I can move that to whichever side of the table I am working on, but it’s not necessary to have. If your mill has a panel with controls already, that should be fine, mine didn’t so I had to build something and the pendant was easier.
I use coast to stop on my mill, doesn’t really need a braking resistor, but some people feel that is safer. It works just fine either way. Mine has a brake lever in case I want to stop quickly, I do that with the larger diameter cutters, but end mills only take a few seconds to stop.
I made a pendant that is wired into the VFD. I can move that to whichever side of the table I am working on, but it’s not necessary to have. If your mill has a panel with controls already, that should be fine, mine didn’t so I had to build something and the pendant was easier.
I would recommend the GS21 over the Teco, cost less, a bit more flexible in programming. You can go 2 wire For-off-Rev or 3 wire with momentary on and off buttons and a forward/reverse switch. The latter is a bit safer and quicker to operate. It also has provisions for a fast emergency stop which would be a reason to have a braking resistor. I can provide you with suggestions for programming and wiring depending on the model and configuration you want. The VFD does not necessarily need to be on a dedicated breaker, but they recommend a 30A. Breaker protects the wiring, not the VFD, and at the price of these VFDs they are mostly not worth repairing. I have done numerous VFD mill installs on the 935, 949 and other mills, they are a simple install. I also have information on adding a tach/ring LED light ring which I recommend, as well as a back gear switch so the VFD motor rotation always remains the same.