Powerflex 525 Losing Parameters at Powerup

I have a system that has 4 Powerflex 525 VFD's 0.5HP, 480VAC, Version 2.002 Firmware. Using Ethernet IP to communicate to the drives from a 1769-L24ER-QB1B controller (V21 Firmware)

2 of the VFDs are being used to run conveyors, they do not do anything special, they have ADC configured, and I have no problems with them.

However, the other 2 PF525's are being used for positioning (Step-Logic) which requires that I write messages to the drive which allow me to change the motion profiles based on product recipes, etc. I am aware that writing too many messages to the drive can destroy the EEPROM, so I have taken the following steps: 1) Made sure that the messages that are being written only happen when a parameter has been changed. 2) Set the value of parameter C121 to '1' Ram Only so that messages that are written should not affect the EEPROM. Because this parameter is set to '1' - I do NOT have ADC turned on for these two drives.

The problem I am having is that intermittently (with greater frequency), the drives lose their parameters (IP Address and all) and go back to out-of-the-box default values when power is cycled on them (Showing an F100 Fault). This happens to both drives. The solution is to remove the Ethernet connection enter the IP address parameters, cycle power, enter all of the necessary parameters again, change C121 back to '1' and then reconnect Ethernet. This keeps the drives running until power is lost again.

I spoke to Rockwell Tech Support and they could not give me any answers and have replaced the two VFD's under warranty, but the problem started again right away with the new drives. I strongly feel that this has something to do with the messaging to this drive, but I can't find anything wrong. I am considering changing to a 1769-L24ERM controller so that I can replace these drives with Powerflex 755 drives that can handle CIP motion without using them in an unorthodox way.

Any ideas would be most helpful

Powerflex 525 seems to have couple of issues while on ethernet. Even with version 2.03 frn, i too face issues on the ethernet link, which drops off , after a power failure and estabilishes only after a power recylce of the drive. My system comprises of 4 pf525 on ethernet with adc

You may try to set the write mode to EEPROM set the IP address and power cycle. After the power cycle set the write mode back to ram. I have not encountered this problem but his is the only thing I could think to try on the 525.

You could also use a switch with a bootp server like the stratix 5700 or another that does dhcp by port, like an n-tron. You could then write the parameters after the comms come online.

Thanks califlash. In fact iam using stratix 6000 switch and the drives on bootp. What happens is after a power failure, many times the link to the drive does not get estabilished, the leds on the powerflex 525 display does not appear and this happens most of the time. But when the powersupply to the drives are recycled, then the link comes up and the 2 led spots on the powerflex 525 drives.

sreemanohar said:

Thanks califlash. In fact iam using stratix 6000 switch and the drives on bootp. What happens is after a power failure, many times the link to the drive does not get estabilished, the leds on the powerflex 525 display does not appear and this happens most of the time. But when the powersupply to the drives are recycled, then the link comes up and the 2 led spots on the powerflex 525 drives.

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Sounds like the drives might be booting back up faster than the switch. If your power failures are short term using a UPS to keep the switch powered might work. Longer term outages power up the switch before the drives.

Powerflex 525 Link not re-estabilishing after a powerfailure

Thanx Mill. Might be, as you said, the powerflex boots up faster, But when looking at the Stratix switch lights and also while accessing the switch on line, after a power failure, stratix gets on line before the Powerflex 525. Hope a solution will come with a new release of firmware from Rockwell automation.

I use Weidmuller managed ethernet switches and have never had issues with my 525 drives. I have probably installed 30 or so without issue.

sreemanohar

Try setting P053 to 4.

I'm having the same problem here in Inversores, could someone help me find the solution?