3-ANNCPU Potential Power Issue

[ElCid2016]

I have an EST-3 system with 2 panels and 3 ANNCPUs.
Upon arrival main panel says Network Panel 3 Fault

2 annunciators were powered off of the main panel 3-PPS that has 4 SDDC cards. I was informed that the panel had stated that the panel had read Aux Pwr Ovld Ckt before they move the power to the power supply in Panel 2.

Investigation found 24VDC power into ANN (Panel 3) was reversed on the left side. Reversing the wiring did nothing. Moved them to the 24vdc to the right and the unit powered up.

Upon power up, Panel 1 panel displays
Network Panel 2 Fault
Network Panel 3 Fault
Network Panel 4 Fault
Network Panel 5 Fault

Went back and removed Panel 3 from the network. Same panels in trouble.

When power was removed from the other annunciators some of the annunciators would come up while others remained in trouble.

Anyone have any thoughts on this?

To top things off the SDU files are encrypted.

[old_tech]

putting 24v on the 485 terminals cooks the 485 circuits. when powered down, the data passes through ok. you'll need new hardware and programming to fix it.

[ElCid2016]

The 24VDC +/- was reversed on the first 24v connection. When I moved it to the other 24v terminal it powered up.

[Leo]

what do you mean "SDU files are encrypted"

[ElCid2016]

Leo,

The SDU file that was in the cabinet are named 01_00_00_6-SDU.axx.

Per this site the .axx indicates they are encrypted.

https://www.lifewire.com/axx-file-2619755

[old_tech]

It's probably fake encryption. your file has a hyphen as opposed to a period. rename it and it will probably import.