power conversion equipment (drives)

[ECE2001]

I have not been able to obtain a response from UL or the manufacturer of the drive so I'll take a stab at it in here.

I have a drive with an SCCR marking of 42 kA. The drive is UL listed as power conversion equipment and so the standard used to investigate products in that category is UL508C. I am not familiar with the specic testing procedures in that standard. Can anyone tell me how the drive manufacturer could achieve such a rating? I need to know the type, or class of fuse used in the test for this product that could give me the SCCR of 42 kA.

UL file

 

[George Stolz]

I'm not going to be much help, but I have a couple questions.

Why is it important, what's brought on your search?

Are there any visible OCPDs in the device? What type, model number, etc?

To be honest, I'm not sure how the UL arrives at the SCCR. Perhaps they just pound a piece of equipment with progressively stronger faults, until the device pops. Perhaps the manufacturer calls out for a certain value when they submit the device for testing, and then the UL tests with that in mind?

 

[boater bill]

UL508C is used by OEM's and panel shops when they provide a value added VFD product. Value added is the breakers, disconnects, bypass system etc. It requires the panel shop to use UL and UR components in their UL accepted applications and documentation to prove it.

If the Drive package is rated at 42KAIC, then that is the short circuit withstand rating of the input device.

 

[ECE2001]

I'm not going to be much help, but I have a couple questions.

Why is it important, what's brought on your search?

Are there any visible OCPDs in the device? What type, model number, etc?

To be honest, I'm not sure how the UL arrives at the SCCR. Perhaps they just pound a piece of equipment with progressively stronger faults, until the device pops. Perhaps the manufacturer calls out for a certain value when they submit the device for testing, and then the UL tests with that in mind?

George, there are no visible OCPDs in the device. The manufacturer has a max fuse rating listed in the installation instructions but no recommendation for type (Class J, Class R, etc.). That is what brought on my search. If the manufacturer does not recommend a specific type of fuse, how do I know what type of Branch OCPD to put upstream? If I can't get an answer from the mfg or UL, then I will have to use the fuse with the best current limit.

 

[davidr43229]

If you give us the manufacturer of VSD and model , we maybe able to help you. Or call your local Electrical Distributor that stocks that manufacturer, they maybe able to help you with any recommended amperages.
I suspect with your Class J or RK-5,RK-1, it is only to protect the wire and not the VSD.
Just my $.02

 

[ECE2001]

If you give us the manufacturer of VSD and model , we maybe able to help you. Or call your local Electrical Distributor that stocks that manufacturer, they maybe able to help you with any recommended amperages.
I suspect with your Class J or RK-5,RK-1, it is only to protect the wire and not the VSD.
Just my $.02

Bosch Rexroth (formerly Indramat)
Power supply HMV01.1R-W0045