Excessive arcing equals excessive current. What motor is causing the arcing? You should probably start there.

I was looking through the remainder of the alarms:

VERSPEED, MISSING PULSE, FIELD OVER I, Heatsink Over Temperature, Motor Over Temperature, OVER VOLTS (VA), Speed Feedback, Encoder Failed, Field Failed, Three Phase Failed, Phase Lock Loop, 5703 Receive Error, Stall Trip, Over Current Trip, Cal. Card, and ACCTS Failed

Many of these have somewhat easy fixes, not always cheap, but at least you have a chance at repair or getting your motor turning again.

Having to replace the power board or the main board probably won't be cheap.

Do you have more pictures? I'd like to see the rest of the machine.

I have used a few Parker DC590+ drives on my last job. I referenced some of my old literature and all the manual says is: Replace power board or chassis.

I know for sure that most troubleshooting and electronic component replacement at the board level is not recommended by Parker. The manual states that the control and power boards, as well as the control fuse F1 and SCR packs are replaceable. I don't see any other references to swapping components.

I guess that's why they would recommend a compete board replacement. You should check your specific manual to see if it's different.

I've had good experience with Ross valves even in dirty environments, but i don't think they are perfect. You may want to experiment with cheaper alternatives.

I just signed up too. I've got nearly 25 years electrical and electronic experience and I also have some time on my hands to share what I can.

Looking forward to solving some problems here. Most of my experience has been in the metals industry working with somewhat large pieces of equipment as well as smaller shop machines. I enjoy troubleshooting PLC's, drives, motors, and just about any kind of electrical automation.

My friends call me Cheller.