Hello,

I'll attach the 1902 MK III manual. It is stating " The 1902 requires approximately 220mA on the +5V, 75mA on the +15V and 20mA on the –15V power rails" - which are the same voltages as the MK IV. And there are some hints about power supply compatibility.

Regarding safety you should use a power supply that is fully isolated according to the needs for medical instruments with direct body connection, but this should be doable. I did not yet find a connector drawing, but I only cursorily read the manual.

Regards