Yaskawa V1000 overload oL1 Fault

[gzPLC]

Using Yaskawa V1000 to drive a 2ft conveyor with has 1HP motor and motor rated current at 1.83A.

I am running the conveyor the whole day, after it running for a couple of hours it will start giving ol1 fault. I try to monitor the current which stays lower than 1.83 the whole time and even at the time of the trip I saw the current was 1.51amps. I do not understand why it is giving me the overload fault.

I am running at 7.5Hz speed the whole time, at a very slow speed(is the application requirement)

And this conveyor is between two heating units, initially, I thought the motor is overheating because of the surroundings but even if that was the case I should have seen the current spike drawn by the motor, which I do not see.

And the motor does get heated up pretty bad too(but the current draw is normal).

There is a gearbox 30:1 to reduce torques/load.

Has anyone of you experienced the same thing and solution?



Thank you,

 

[rupej]

Some (most?) drives reduce the overload setting when running below 60hz due to the assumption that the motor is cooled by its own fan and is not getting adequate airflow at low speeds. It may be something you can disable if you feel the motor is not at risk.

 

[JTCat]

Have you replaced the motor? That low of a speed surely is cooking the windings.

 

[pturmel]

Your typical AC motor is only rated for 4:1 turn-down--so 15Hz would be the minimum safe frequency for extended lengths of time.



Get a new gearbox that lets you run closer to normal frequencies.

 

[gzPLC]

Motor and the drive both are new and this is a new setup.

 

[gzPLC]

Your typical AC motor is only rated for 4:1 turn-down--so 15Hz would be the minimum safe frequency for extended lengths of time.



Get a new gearbox that lets you run closer to normal frequencies.

In that case to run the same speed on the application side and at a higher frequency on the drive I will have to go even lower gearbox 50:1 i.e. 50 input rev to 1 output rev.


Do you think it will help? I also strongly feel it's all because of the very slow-speed application.

 

[pturmel]

Yes, if you need 7.5Hz with a 30:1 gearbox, you will need a 60:1 gearbox to run at 15Hz. That would be a minimum. Consider 200:1 or more to get close to 60Hz.


Do you ever need to run the conveyor faster? If so, pick the gearbox to allow that, but certainly no less than 60:1.

 

[jraef]

Some (most?) drives reduce the overload setting when running below 60hz due to the assumption that the motor is cooled by its own fan and is not getting adequate airflow at low speeds. It may be something you can disable if you feel the motor is not at risk.

Yes, the V1000 absolutely will adjust the OL protection based on the expected heating effects of reduced speed. You have to actually read the manual about how to program the OL setting, there are other settings that allow different actions based on the type of motor you have.

 

[gzPLC]

Do you think switching to a different drive might help? Such as powerflex 525 instead of V1000?(instead of changing the gearbox)

Will it handle the motor differently?

 

[gzPLC]

Yes, the V1000 absolutely will adjust the OL protection based on the expected heating effects of reduced speed. You have to actually read the manual about how to program the OL setting, there are other settings that allow different actions based on the type of motor you have.

Yes, I saw in the manual there is a parameter in the Motor protection Section called Motor protection selection L1-01.

If I set it to 2, I can continuously run full load at a speed from 6-60 Hz range. Condition: Considering the motor is designed to cool itself at 6Hz.


As my motor seems to not have a fan

So this will be my game plan, change L1-01 to 2 and use an external fan to cool the motor. And see if it trips.

We will find out Monday!

 

[GaryS]

You said you tried to monitor the current
how were you doing that my guess is that you uase a clamp on AC amp meter
they should never be used with vfd powered motor they are all designed for 50-60Hz syne wave they deffently don't read well at 7 hz
you should look at the vfd display for the motor load
it is possable that you are actuallly going into overload at low speed
the V1000 dose not do well below 6 hz under high load that could be higher
the A1000 would be a better choice and put an encoder on the motor to increase the proformance

 

[gzPLC]

You said you tried to monitor the current
how were you doing that my guess is that you uase a clamp on AC amp meter
they should never be used with vfd powered motor they are all designed for 50-60Hz syne wave they deffently don't read well at 7 hz
you should look at the vfd display for the motor load
it is possable that you are actuallly going into overload at low speed
the V1000 dose not do well below 6 hz under high load that could be higher
the A1000 would be a better choice and put an encoder on the motor to increase the proformance

Gary, I used the VFD display to monitor the live current draw, I saw it going from 1.48-1.51 Amps and it trips around 1.51Amps.

There is a monitoring parameter U1-03 which captures the amps at which the drive gave the overload fault. But in this case, as the current draw never reaches the motor rated current set in the vfd i.e.1.83Amps I guess due to this reason it shows me 0 Amps in this parameter.

I do not have an A1000 but I do have a spare Powerflex 525, if you have used it...do you think Powerflex 525 will perform better at 7.5Hz compared to Yaskawa V1000?

 

[rupej]

Do you think switching to a different drive might help? Such as powerflex 525 instead of V1000?(instead of changing the gearbox)

Will it handle the motor differently?

No. The issue is not the drive. You've been given the reason the drive is tripping and also multiple solutions.

 

[Gene Bond]

It sounds like you have a TENV (Totally Enclose, Non Ventilated) motor, so adjusting the overload so it is allowed to run FLA down to 0hz should be OK.

However, you stated, 'And the motor does get heated up pretty bad too(but the current draw is normal).'

Depends on how hot you consider hot... motors are hot, when run at full torque, or close to it.

Is there perhaps a thermal protector in the motor you could connect for further protection? Typically motors designed to run these low speeds (vector duty motors, typically), have thermal sensors for this purpose.

And to echo, the Rockwell drive will not solve your problem. It should be kicked back to the engineer who screwed up the gear ratio calculation.