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By Rob1974
#1294409
Hi ive just bought a startrite ta300 and want to convert it to run off domestic 240v. Ive had a read through previous threads and understand 2 options are to change the motor to a single phase motor or get a vfd phase invertor. The saw ive bought has a motor brake fitted and i like the idea of a brake and soft start on the motor. So i am favouring getting a vfd. Ive no experience with this allthough understand a bit about wiring motors. My quetion is the motor in the saw says 240/415 v so i believe it can be converted allthough the wiring in the junction box will need to be changed. Will this affect how the brake works. Any advice or pointers would be greatly appreciated.
By Hornbeam
#1294439
Using a VFD, you have options within the set up to adjust the ramp rate up and down and in some there is also a braking resistor.
It is by using these parameters that you effectively brake teh motor not by DC injection.
I use VFDs on a couple of machines. Found on the bandsaw a slower ramp up rate puts less strain to get everything up to speed. If you set too fast a ramp rate the VFD can trip out
Ian
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By Ttrees
#1294444
Thanks to Hornbeam for clearing this up,
Just for folks interested, tripping out an inverter just means you hit reset or stop on the keypad
and your back in business again.
It doesn't mean it blows up or anything.
By delaney001
#1296399
Is the VFD route managable in a DIY sense? I am looking at a planer thicknesser and there are great 3 Phase machines to be had for reasonable money, but would need to be converted. I would consider myself reasonably handy, but electrics arent my strong point. Is it best avoided if not an electrician by trade?
By guineafowl21
#1305178
Ask the seller to take a pic of the motor nameplate and, if possible, the motor wiring connections. You’re looking for some mention of “dual voltage” or “240/415V” or similar. There should be six connections in the wiring box.

If you have the above, then it’s a case of converting from left to right:
https://qph.fs.quoracdn.net/main-qimg-d ... cad5b0787b

If not, you’ll have three connections and the motor is wired permanently in star, and needs proper 3ph 415V. If you’re lucky, you’ll have a motor rewinder nearby who’ll be willing to bring out the star point so you can convert to dual voltage as above, or have a go yourself of you’re reasonably handy. Alternatively, there are inverter drives that will put out 3ph 415V from 1ph 240V, but they are expensive. Look for “dual stage” types.
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By Ttrees
#1305181
delaney001 wrote:Is the VFD route managable in a DIY sense? I am looking at a planer thicknesser and there are great 3 Phase machines to be had for reasonable money, but would need to be converted. I would consider myself reasonably handy, but electrics arent my strong point. Is it best avoided if not an electrician by trade?


If it has two motors it complicates things, but some have mentioned that it is possible with a single VFD/inverter.
You should make a new thread about it and get these things up for us :)

Very easy to wire these things up for a complete novice that knows nothing beyond wiring a plug for a machine with a single motor.
It's more of a case of spending a day or two reading Robert/Bob Minchin's induction motor PDF over at the wood haven 2 underneath Bob AKA, 9fingers the mod's signature.
This will explain the terminology that will be entered into the VFD parameters,
like max frequency which is 50hz in Europe for induction motors, compared to 60 hertz in the USA.
Motor pole number, and RPM are two more important parameters.
The three of these parameters all relate to the speed of your motor.
There the most important things to know so you don't program your motor for warp speed.

Loads of Startrite 275 threads explaining all this for instance.
There seems to be VFD/ inverters got for an obtainable price, that will power high voltage 380v (star configuration) machines now, so you don't have to seek out a machine with a dual voltage motor that can be wired to low voltage 240v (delta configuration)

startrite-275-table-saw-conversion-3-phase-single-phase-t106896.html?hilit=inverter%20startrite&start=30

can-anyone-fit-a-3-phase-inverter-for-me-t109500.html?hilit=inverter%20startrite&start=15

3-phase-to-single-phase-startrite-275-conversion-from-3-ph-t91106.html

startrite-tilt-arbor-circular-saw-t88484.html

Beware folks
One ebay seller has Isacon/askpower drives pictureed, but is sending the mini VFD's!
I doubt they would hold up, as these things have cramped together parts already.
Ask for the dimentions of them if you are looking, so you can get a refund if they try anything sneaky.

Tom