Thread: VSD power tests

Originally Posted by BobL

That sounds pretty much like what I saw, except at a higher frequency but if the load required to feed power is high enough that will happen at lower frequencies.

You are suggesting that the VFD is reaching full power? The max input amps I have seen is around 8A. The VFD is rated at 23A max input. The EBay ammeter could be inaccurate?

As the VFD is not rated equal to the motor I did not expect to get full power and speed, but that does not mean that I should not push it to see what it is capable of.

Dean

Dean,
have you tried it yet with 29Hz as the base frequency setting? I was amazed at the results Bob got with that setting compared to 50Hz. That's why I thought it would be such a great finding for Aaron's big old Deckel motor. I'd forgoten about your 2-speed motor....
I would not expect you to get higher speed - but better torque at design speed and a little below and above. To get your motor to run faster (than 85Hz), you clearly need 415V to saturate the coils.

Originally Posted by jhovel

Dean,
have you tried it yet with 29Hz as the base frequency setting? I was amazed at the results Bob got with that setting compared to 50Hz. That's why I thought it would be such a great finding for Aaron's big old Deckel motor. I'd forgoten about your 2-speed motor....
I would not expect you to get higher speed - but better torque at design speed and a little below and above. To get your motor to run faster (than 85Hz), you clearly need 415V to saturate the coils.

No, I haven't Joe. I will give it a try shortly. As the lathe is essentially working perfectly except for that, I have not given it a lot of thought.

Dean

Originally Posted by jhovel

Dean,
have you tried it yet with 29Hz as the base frequency setting? I was amazed at the results Bob got with that setting compared to 50Hz. That's why I thought it would be such a great finding for Aaron's big old Deckel motor. I'd forgoten about your 2-speed motor....
I would not expect you to get higher speed - but better torque at design speed and a little below and above. To get your motor to run faster (than 85Hz), you clearly need 415V to saturate the coils.

me to Joe ive been looking at all this. I really need to get or make a mt4 boring head arbor and get the collet sleeve out of the mill spindle

I set tha base frequency to 29Hz today. It did not make much difference. The 85Hz max was raised to about 90Hz. This was in a lower gear by the way. 65% of max speed (ratio). In top gear I was lucky to get to 80Hz. Another gear lever drops the speed right down. With this setting I was able to run the lathe at 120Hz which is the set max. The issue seems to be related to amps only. I cannot get it over about 8.0A. This may be due to a setting, or a fault with the unit. I cannot say. I don't recall seeing any setting that refers to current limiting, although I was under the impression this was available.

Dean

Dean,
do you mean your VFD wont let you set that parameter higher than 8.0A? Or do you mean your motor won't draw more than 8A?
What size and make is your VFD?
One of my Huanyang 3kW ones goes to 11A, the olther to 13A..... a bit of cheating or spin going on there I fear....

Originally Posted by jhovel

Dean,
do you mean your VFD wont let you set that parameter higher than 8.0A? Or do you mean your motor won't draw more than 8A?
What size and make is your VFD?
One of my Huanyang 3kW ones goes to 11A, the olther to 13A..... a bit of cheating or spin going on there I fear....

I mean I have yet to find a setting that says to me it is for limiting amperage. It is a 7.5hp motor so it has plenty to go. I haven't worried too much up til now as it has not been a problem, yet.

The VFD is a 4.5kw Huanyang.

Dean

Hi Dean,

Originally Posted by Oldneweng

I set tha base frequency to 29Hz today.

Base freq shouldn't make any difference above 50Hz. If it does there is something else going on that I don't understand.

Stuart

Originally Posted by Stustoys

Hi Dean,



Base freq shouldn't make any difference above 50Hz. If it does there is something else going on that I don't understand.

Stuart

Well that makes at least 2 of us. I can no longer read stuff like this in little tid bits over a long period of time and retain it all. I would have to read thru all of it while following up references to understand. Somehow I just never get the time to do that. After largely neglecting the property for some months I have been forcibly redirected. Patching a stuffed fence at the moment, but that is just the tip of the iceberg. What I need is to find things I have to make, in the shed. I do want to make a post driver.

Dean

Dean, good luck with the chores!
Setting the current limit would be PD142 (rated motor current) and the rated maximum of the inverter would be readable in PD174....

Originally Posted by jhovel

Dean, good luck with the chores!
Setting the current limit would be PD142 (rated motor current) and the rated maximum of the inverter would be readable in PD174....

Thanks Joe. I remember now. PD174 gives 17 and I had set PD142 to 12 as I did not want to overload the standard circuit that the VFD is connected to at the moment. At this rate I am not going to need a new heavy circuit. I changed PD142 to 17 today, but it did not change anything. I am beginning to wonder if this VFD has a fault.

Dean

How are you measuring the current, Dean? Are you just relying on the VFD option to display the current?
I think BobL in his tests found that to be inaccurate to say the least....

Hi Dean,

Just to be sure. You are running a 240V VSD on a 415V 2 speed motor?
If so there its unlikely there is anything wrong with your VSD or motor. You just arent going to get full power and above 50Hz the power goes down fast, as shown by the black lines in this graph.

https://www.woodworkforums.com/182106...ml#post1789120

Have you kept the "two speed" wiring on your motor?

Stuart

Originally Posted by jhovel

How are you measuring the current, Dean? Are you just relying on the VFD option to display the current?
I think BobL in his tests found that to be inaccurate to say the least....

That's one thing I haven't checked, VSD display current versus the reading from a current clamp on the output of the VSD.