In the setup where the redundant power connections to a controller power supply are used, is there a diagnostic parameter that can be referenced to determine when one of the redundant sources of power to the controller power supply has dropped voltage? The CIOCs have this diagnostic, but I have not found one for the controllers?
I understand that there is a hardwired contact output on the controller power supply, but does this contact open when only one or both of the redundant power feeds drops voltage? This is only useful if you have a separate controller in a separate cabinet nearby to bring this contact in to.
Has anyone investigated these features at all?