Hey erick. Just updated my build thread. Not sure how to post link but look for steel/aluminum fixed gantry thread. Should be up the top somewhere.
Cheers.
Well...after some testing i would say it's not a 2.0 Kw/380V motor
More like a 1.1Kw/220V motor...will do a few more tests at home.
Hey erick. Just updated my build thread. Not sure how to post link but look for steel/aluminum fixed gantry thread. Should be up the top somewhere.
Cheers.
Thanks...just had a look, great job mate
How are you testing the torque?
You should be able to see how much power is being pulled from the vfd. Torque and power are two different things though. There is no reason why a 2.2kw spindle should automatically produce more torque than a 1.5kw one. It all depends on the base speed.
i.e. a Spindle that hits 1.5kw at 12000 rpm would produce more torque than a spindle that reaches 2.2kw at 24000.
If you find out the base speed of the motor then you can work out how much torque the spindle should have. You can then tell on the vfd if it is drawing 2.2kw at 240v at the base speed.
Been busy with other stuff....will re visit the motor. Like i said, i ordered two motors....1.5KW/18000rpm/220V and a 2.0Kw/18000rpm/220v. When they arrived the 2.0 KW motor plate indicated 380V/2.0Kw.
When i contacted them they asked me to open the terminal box so they can check if its a 220v or 380v motor. They said it was wrongly labelled 380v...its actually a 220v/2.0 Kw motor. I am not convinced that it's a 2.0 Kw motor....
The initial test i did on both motors indicated that the 1.5Kw motor had more torque....reason i though possibly the motor was a 380v motor....well i got motor heating when running it at 380V, more heating than i would like/expect. Best is to do proper load tests. I was doing my initial tests at the same speeds and loads....both motors run at the same speed through the freq range. So i can confirm that both are 18000rpm motors
The top speed and the base speed are two different things. You can have two 2.2kw spindles with a top speed of 24000 rpm but one could have a base speed of 12000 rpm and the other could be 24000 rpm. In that example, the 2.2kw spindle with the 12000 rpm base speed would have twice the torque of the other, even though they are both 2.2kw and both have top speeds of 24000 rpm.
Motors have constant torque up to the base speed and (in scenarios where the top speed is higher than the base speed) torque gradually declines as the speed rises above the base.
If both of your spindles have a base speed of 18000 rpm then the 2.2kw spindle will have slightly more torque than the 1.5kw if it is set up right (and not broken).
Torque is just horsepower at a given speed. 2.2kw at 18000 rpm is always 0.9 foot pounds. A motor hitting 2.2kw at 12000 rpm is always 1.3 foot pounds. See for yourself:
https://spicerparts.com/calculators/...que-calculator
If both spindles are reaching 18000 then it is unlikely that you have the wrong voltage. I have never tried it but my bet is that if you push 380v into a 240v spindle it would run too fast for a short time before burning out (if it worked at all). It sounds like Hertz make duel voltage spindles like mine. My spindle can be wired for 240v or 380v. You can look in the spindle terminal box to see which wire pattern your one has.
I suggest that you go back to the manufacturer to get a correct name plate. I can't see how you could set it up correctly (and safely) without this info.
Mate i know how motors work...
The speed of these motors has nothing to do with applied voltage....whether you apply 220 v or 380 volts....the speed will be the same if the poles are the same and the freq applied are the same. No these motors are internally connected, so you don't have the option to change between star and delta. If that were the case then i would not have to wonder what the true applied voltage should be. If you read correctly you will find that i did apply 380 volts to the motor. Many 220 volts motors will start and run on a too high voltage but not for long.....like i said there was some heating but not extreme, but enough to convince me that this is in fact a 220v motor. With regards to speed, they both 300HZ/18000rpm motors. I will not run them past this speed even though i could. Fact is i paid for a 1.5kw motor that i received but the supposedly 2.0kw motor is not that.
Going back to the manufacturer won't help...i tried that. Like i said i will do more tests when i get the time
That's not accurate. The VFDs vary speed by varying voltage. You can check the voltage being output on the vfd. My spindle is a 240v one. At 24000 rpm is shows 240v out, at 12000 is shows 110v.
If you are sending 2.2kw to the spindle and it is working properly, it's a 2.2kw spindle. If it hits 2.2kw at 18000, you have 0.9 ft pounds of torque.
How are you measuring torque?
DC motors (generally) vary speed by varying the motor supply voltage.
AC motors like the Hertz spindles require a VFD - Variable Frequency Drive to gain variable speed control. As the name suggests, the drive changes the supply frequency to the motor to change the speed. The voltage does not change.
Not sure what you are reading regarding the voltage output on your VFD unless you have a DC spindle.
Update. The Hertz spindle is still working great, i sold the spare unit and just bought another two units. One for myself and one for sale
220V_18000rpm_300Hz_2.0Kw....the heavier duty one that is suited for aluminium milling