VFD Fault : Thermal Overload on Volts/Hertz Set to High Starting Toque

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Saturn_Europa

Saturn_Europa

Senior Member
Location
Fishing Industry
Occupation
Electrician Limited License NC
I work on a fishing boat. There are 3 twenty horse power motors that drive high pressure pumps into a common header. The header is connected to pressure washer wands thru out the factory.

I installed a new motor: https://www.radwell.com/en-US/Buy/TOSHIBA/TOSHIBA/0204XDSB42A-P/ its a 256T frame.

The motors are supplied by 3 identical drives. Durapulse GS3-4020 . I did not change any settings when I installed a the new motor. The voltage, HP, RPM matched the old motor that was removed.

The motor will not start with the Volts/Herts setting (2.00) on 01 High Starting Torque. The plc is giving a command of 34 hertz, the output hertz is 0.5 and the amps are 55. The motor is shaft is barely turning and the drive faults out. I disconnected the lovejoy from the pump and tried to run the motor unloaded. Same thing. I thought the motor was singling phasing at first. But everything is correct.

When I set 2.00 to 00 General Purpose the motor starts right up and follows the commanded hertz.

The other 2 motors are set to High Starting Torque and have not been giving me a problem.

Any ideas on why the new motor does not like the High Starting Torque.



The pump is similar to this:

5 Frame Plunger Pump - 310 Alternate Spec | Cat Pumps

www.catpumps.com www.catpumps.com
 
Saturn_Europa

Saturn_Europa

Senior Member
Location
Fishing Industry
Occupation
Electrician Limited License NC
I only skimmed over that page. Setting P 2.10 is 00 = V/Hz without encoder feed back.

from 3-14

"Autotuning is required only if using Sensorless Vector Control Modes P 2.10 = 02, 03, 05"

I may need to change the control method of the drive.
 
Saturn_Europa

Saturn_Europa

Senior Member
Location
Fishing Industry
Occupation
Electrician Limited License NC
Luckily the two other pumps are running fine.

That might be an idea. The pumps are all together and the leads are long enough to change around.
 
Jraef

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
The drive is acting as if it is immediately going into Current Limit, which it might do if there is a high resistance fault inside. Might be a bad connection, might be a bad motor. It happens... Do you have a megger?
 
A

alexfox1986

Member
Location
Manchester
Occupation
Electrical Engineer
Saturn_Europa said:
I work on a fishing boat. There are 3 twenty horse power motors that drive high pressure pumps into a common header. The header is connected to pressure washer wands thru out the factory.

I installed a new motor: https://www.radwell.com/en-US/Buy/TOSHIBA/TOSHIBA/0204XDSB42A-P/ its a 256T frame.

The motors are supplied by 3 identical drives. Durapulse GS3-4020 . I did not change any settings when I installed a the new motor. The voltage, HP, RPM matched the old motor that was removed.

The motor will not start with the Volts/Herts setting (2.00) on 01 High Starting Torque. The plc is giving a command of 34 hertz, the output hertz is 0.5 and the amps are 55. The motor is shaft is barely turning and the drive faults out. I disconnected the lovejoy from the pump and tried to run the motor unloaded. Same thing. I thought the motor was singling phasing at first. But everything is correct.

When I set 2.00 to 00 General Purpose the motor starts right up and follows the commanded hertz.

The other 2 motors are set to High Starting Torque and have not been giving me a problem.

Any ideas on why the new motor does not like the High Starting Torque.



The pump is similar to this:

5 Frame Plunger Pump - 310 Alternate Spec | Cat Pumps

www.catpumps.com www.catpumps.com
Click to expand...
It's possible that the new motor may have a different internal winding configuration, which could cause it to behave differently when using the High Starting Torque setting on the drive. It's also possible that the motor may have a higher or lower starting torque than the previous motor, which could affect its ability to start under certain settings.

One thing to check is the motor's nameplate data, which should include information such as rated voltage, current, power, and speed. Make sure that the nameplate data matches the information entered into the drive, and that the drive is configured to operate within the motor's rated specifications.

Another possibility is that the drive may need to be adjusted to better match the characteristics of the new motor. You may want to consult the drive's manual or contact the manufacturer for guidance on how to configure the drive for best performance with the new motor.
 
Saturn_Europa

Saturn_Europa

Senior Member
Location
Fishing Industry
Occupation
Electrician Limited License NC
Up date to the update. The drives started acting up again. Command from PLC was 34 hertz. Drive out put was 0.5 hertz followed by a current overload alarm in a few seconds.

I changed the setting from high started torque to general purpose. Everything seems to be working.

The old drives were probably fine.
 
Saturn_Europa

Saturn_Europa

Senior Member
Location
Fishing Industry
Occupation
Electrician Limited License NC
Its a little odd because the drive settings havent been changed since install about 5 years ago. Its been an off and on problem according to some of the guys and just got worse this season.
 
G

garbo

Senior Member
Saturn_Europa said:
I work on a fishing boat. There are 3 twenty horse power motors that drive high pressure pumps into a common header. The header is connected to pressure washer wands thru out the factory.

I installed a new motor: https://www.radwell.com/en-US/Buy/TOSHIBA/TOSHIBA/0204XDSB42A-P/ its a 256T frame.

The motors are supplied by 3 identical drives. Durapulse GS3-4020 . I did not change any settings when I installed a the new motor. The voltage, HP, RPM matched the old motor that was removed.

The motor will not start with the Volts/Herts setting (2.00) on 01 High Starting Torque. The plc is giving a command of 34 hertz, the output hertz is 0.5 and the amps are 55. The motor is shaft is barely turning and the drive faults out. I disconnected the lovejoy from the pump and tried to run the motor unloaded. Same thing. I thought the motor was singling phasing at first. But everything is correct.

When I set 2.00 to 00 General Purpose the motor starts right up and follows the commanded hertz.

The other 2 motors are set to High Starting Torque and have not been giving me a problem.

Any ideas on why the new motor does not like the High Starting Torque.



The pump is similar to this:

5 Frame Plunger Pump - 310 Alternate Spec | Cat Pumps

www.catpumps.com www.catpumps.com
Click to expand...
 
G

garbo

Senior Member
Don't know if this works for you but when we replaced or installed VFD'S our great local company that sold us the drives only charged around $150 to 225 to perform start ups and gave extended warranty ( free parts & labor ) to three years on the 5 to 200 HP drives we purchased. I would P touch the experation date on drive. Several times the drive tech had to replace an expensive board that more then paid for start up fee. We would keep some drives in bench stock and in an emergency install & start them up ( after punching in motor info ) then have tech check our work and give us extended warranty. Our genius drive tech only worked on drives for over 20 years and with over 500 drives could never stump him. A few times he had to get his thick programming Manuel out to make a parameter change.
 
Jraef

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
“High starting torque” (aka “Torque Boost”) when using V/Hz is accomplished by purposely increasing the V/Hz pattern to provide more volts in the beginning. Doing so increases the risk of saturating the windings, but the issues is that it is only sone briefly during the first few seconds to accelerate a high friction or high inertia load. I can imagine that the possible need for that is because you are pumping into a common header, with no check valves on the individual pumps, so starting any one of them could mean having to start against a higher static head, requiring more starting torque from the motor. Back in the days when vector control was unheard of yet or required a much more expensive drive, we used the Torque Boost feature, even though it was kind of a craps shoot as to how effective it would be. That’s because different motors have different saturation patterns, so one motor may not act the same as another.

After most commonly available drives began coming with Sensorless Vector Control as standard, the V/Hz Torque Boost feature kind of got sidelined, because once properly set up, SVC was MUCH better at providing all the torque you need for most applications. If this were my equipment, I would change to using SVC and doing a Static Autotune.
 
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