Dear sir,

I am using MM440 for pipe rotator purpose and we want to run it at 2.5Hz but i think due to heavy weight rotator is not rotating.When i increase Hz to 6 then it start rotating.

I tried to run it with continue voltage boost but problem not resolve i also tried to control it on SLVC control method but my problem is same.

Can any one suggest me any idea about it.

Regards,

Pankaj Tiwari 

pankaj_054

Dear sir,

I am using MM440 for pipe rotator purpose and we want to run it at 2.5Hz but i think due to heavy weight rotator is not rotating.When i increase Hz to 6 then it start rotating.

I tried to run it with continue voltage boost but problem not resolve i also tried to control it on SLVC control method but my problem is same.

Can any one suggest me any idea about it.

Regards,

Pankaj Tiwari 

We do not work with drives from Siemens, so I do not know them. I have seen a specification from a manufacturer, where its newest generation of drives put out driving torque at 0.5Hz. Previous generations could only achieve that above 8.0Hz or 6Hz.

The MM440 is not the newest generation of drives. So I doubt you will be able to achieve your goal. Driving at so low frequency does not make sense to me. I would imagine having a gear ratio (and motor power) that would bring the required speed within 30Hz to 80Hz when using a asynchronise motor. Running asynchronise motors at low frequency will also need active cooling.

What is your situation? What type and size of motor are you using? 

Dear sir,

Thank you for quick reply...

I am using a rotator with two motor each of 3.7kw induction motor it run with mm440.

My application is to rotate a steel pipe of large diameter at low frequency to do plasma cutting on pipe.As per operator requirement he wants to run motor very slow say 2.5hz ,but due to heavy weight of pipe rotator does not rotate.Also it is not continuous process so cooling of motor is not a trouble.

How can I drive rotator on low frequency????

Regards,

Pankaj Tiwari

pankaj_054

Dear sir,

Thank you for quick reply...

I am using a rotator with two motor each of 3.7kw induction motor it run with mm440.

My application is to rotate a steel pipe of large diameter at low frequency to do plasma cutting on pipe.As per operator requirement he wants to run motor very slow say 2.5hz ,but due to heavy weight of pipe rotator does not rotate.Also it is not continuous process so cooling of motor is not a trouble.

How can I drive rotator on low frequency????

Regards,

Pankaj Tiwari

Operating with two motors from a single drive, Sensorless Vector Control should not be used, SLVC will be unstable.

The frequency 2.5 Hz, with a MM440 is low, torque will be low and risks damage to the IGBT. The IGBT 'ON' time will be long, which may damage the output stage.

The only effective solution would be to modify the drive gear ratio to enable a higher, and more stable frequency.

Tractor

Dear sir,

Thank you so much for explanation.

Regards,

Pankaj Tiwari