Power Flex 753 current limting

Hello all, I have a 250hp PF 753 driving a water pump. New installation and doing the start up and programming. Everything looking good, but I am getting an overvoltage fault with current limiting fault in the fault list. I noticed this when I saw the amp indication drop for a short time and the HZ decreased to 52 from 60. What parameters should I be looking into for this problem? thanks

I don't have a PF 753 manual in front of me, but it seems you have two different issues. Over voltage is usually when you decelerate too quickly and it dumps power back to the line. Over current is when you're drawing more current than the drive is set up for. The drive limits the current by decreasing the Hz. Are you drawing more current than the drive is set for?

These faults are usually eliminated by increasing the acceleration (over current) time and the deceleration time (over voltage). This type of problem is common with any kind of high inertia rotating load.

You may also look at the current limiting function. This is used to "clamp" or reduce the speed when the load draws more than a set current, preventing trips and overloads.

First off, see if you have the "DC Bus Regulation Mode" enabled or not, it is P372. For a water pump, you should probably not have that enabled (setting "0").

The factory default value is "1" which enables it and adjusts the frequency output to try to avoid a DC bus over voltage condition, overriding a commanded frequency or accel/decel profile. You usually do NOT want that with a centrifugal pump. People often don't understand what it is and leave it enabled without learning first, leading to odd things happening that they can't understand. If it is disabled already, post back and we can go from there.