3 replies to this topic

[Dribble]

Greetings all. First time poster here.

I'm hoping I might get anyone's opinion on the particulars of setting up a Drive (SEW) to detect output overcurrents (load), and what responses are possible.

I'm using the Drive in a hoisting application, and need to invoke some type of Fault output, or Disable, if the load weight increases by a certain amount (say 10%).
I'm assuming the load increase does actually register as an output current increase within the drive.

There is a Parameter 303 'Current Limit', but I'm not sure how to apply it properly, or how fine and accurate it's detection is.

Ideally I'd like to trip the Fault relay, or put the Drive into 'Rapid Stop/Fault' mode if an overcurrent is detected.

Hoping to get anyone's views on how they might have achieved this in other applications, or if there are better ways to do this WITHIN the drive.

Thanks.

[Carl]

Hello Dribble
Welcome ton the forum. Most of the drives I've worked on have had some type of potentialy free fault relay that can be set for a fault ...overcurrent, over voltage, over temp etc etc
Current limit limits the current look for something like OCT over current trip.

If the drive has none of these features you could alway buy a dedicated bit of hardware. The measurement of physical load on a motor is a bit more involved than measuring the current.

[fintanlawlor]

Hi Dribble

If you email SEW Eurodrive in the UK & pose your questions to Bob Phillips, he will be able to point you in the right direction.

Regards

Fintan Lawlor

[bob]

The idea to current limit as a sort of overload is wrong. You ought to use an overload limiter, strain gauge type, to limit your hoist to a certain particular weight. The current limit on the drive will try to limit the current taken by the drive to prevent overcurrent.
Hope this helps.

Bob