Siemens MJ-1 MJ-2A MJ-3 MJ-3A Repair

Siemens Regulator Controls. The MJ1 MJ2A MJ3 MJ3A were the first microprocessor based controls. They differ mainly in processor type and speed, although the MJ-3A has a few additional features. Linemen-friendly (they have knobs), they offered as an option a “DataPak” and other options such as external voltage reduction and High/Low Voltage overrides.

MJ-2A (MJ-1 and MJ-2 look identical in front)
MJ-3A