I could not find anything on disabling the sleep mode on the device, I could only find how to modify it which it sounds like you already know how to do.
I have a Xerox WC 7855 Machine which sadly not waking up from Sleep Mode. It waking up from Power Saver mode without any issue but once the machine goes to Sleep mode (which the max time out I can give is 30 min after power saver mode) the machine refuse to wake. Even pressing the physical button or pressing power button does nothing. I have to remove the plug and then plug back in to use the machine. Is there any way to disable the sleep mode or time it like 240-300 min after powersaver mode.??
Any NVM Data that can help??