Power Flex 40 question

SW (software) overcurrent. I believe this means that the setting for software instantaneous current was exceeded where a normal overload may take longer to trip, I think the software overcurrent fault usually means you hit your setting for the related parameter(s) very quickly. If it accompanied a true jam or overload condition, then it did what it was intended to do, above and beyond (depending on how you set it up) the motor FLA limit.

This can be done to protect product, drive systems like chains or belts, conveyors, not to mention the stalled motor which is actually now a heater for the duration of the overload time... It is normally set a little above the max normal peak during full duty operation to save you a bunch of mechanical work or product if something snags. There should be a software current setting. I would study the drive readout for current while normally loaded and compare that with your software overcurrent limit.

thanks for the quick reply, the parameter is set the same as the overload current at 24 amps. Its a 10hp motor runing a collection line conveyor belt. I believe is was shut off for a jam and then this error came up. Should the software current trip be set the same?

By shut off, you mean powered down?

It might be possible that it powered up and was still jammed or in a bind somewhere. Or, it could be, that it was a one off event after powering up, a nuisance fault that may or may not happen again. I never worry too much until the 2nd occurrence...

Having it set the same probably means that you will see this software overcurrent fault in any overload condition before the normal motor ol fault you may expect.

It might be that the software current was set there intentionally. I don't remember what the book says about the default value.

You are basically setting the drive up to limit the motor to less than one second at FLA by having the value set the same. So it is a (kinda sorta) 9.9HP motor now...This can be a good thing, but it may have been a misunderstanding (easy one) by someone wanting to make sure they entered the FLA value where they thought it should be. I know by default, this feature is not enabled, you have to enter a value appropriate for instantaneous ( some short term average if I recall less than a half second).

When I used it, I always watched the amp reading under normal condition. I would trend it with drive explorer (or one of its older cousins) when I could, then make sure I set it well above the peak (like 150% or more). This was usually in reaction to a failure that ripped a belt or squished a bunch of goodies for a whole minute before faulting. So then, if something broke loose, it would fault first. We had it detect a split key in a long conveyor that was a really light load all except for about 5 degrees of its rotation when the mangled half key would snag the vacant groove in the pulley, they would reset it, the shaft would go one time around...spike at double my setting and shut down.

It was shut off by our control room....stop was hit. Thanks for the advice it will be followed. Might of been a nuisance trip.

icehube said:

thanks for the quick reply, the parameter is set the same as the overload current at 24 amps. Its a 10hp motor runing a collection line conveyor belt. I believe is was shut off for a jam and then this error came up. Should the software current trip be set the same?

Click to expand...

A098, where this is programmed, is meant to trip at the set level within 100msec, basically instantaneously. Think of it as an electronic shear pin. The overload current will trip if that setting level is maintained for 60 seconds. If you have them both set the same, it will ALWAYS trip the instant the current reaches that level, which in my opinion would be a nuisance. But without knowing the mind of who set it for that, you risk possible mechanical damage to something. It would not be the motor, but it might be based on something that the motor is driving. I can't imagine what that could be on a conveyor, but I can't see it either.

I will say that often times things like that happen because whomever programmed it had no clue, AND didn't bother to read (or couldn't understand) the manual.