M

Magnetic Amplifier     Sometimes abbreviated "Mag Amp," a saturating inductor which is placed in series with a power supply output for regulation purposes.

Margining     Adjusting a power supply output voltage up or down from its minimal setting in order to verify system performance margin with respect to supply voltage. This is usually done electrically by a system-generated control signal.

Maximum Load     The load specified for continuous operation. This will be the load used for safety applications.

Minimum Load     The minimum load current/power that must be drawn from the power supply in order for the supply to meet its performance specifications. Less frequently, a minimum load is required to prevent the power from failing.

MTBF - Mean Time Between Failure     A measurement of the relative reliability of a power supply based upon actual operating data or calculated according to MIL-HDBK-217.