Nastec HMA Series, Operating Manual

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1. Introduction to HMA
HMA is an electronic device for switching between power sources that integrates multiple functions:

Automatic power source management: HMA, combined with any MultiPower “HMA ready” device, switches
between AC power (mains or generator) and DC power (photovoltaic panels) completely automatically, based on the
programmed logic.

Mechanical disconnection of the two power supplies: Two interlocked contactors guarantee the uniqueness of the
power supply and ensure separation in order to ensure maximum electrical safety.

Control of auxiliary generator: When the AC power is provided by a generator, HMA is able to start or stop it
according to need. HMA also monitors any signs of failure or running out of fuel.
Five programmable switching logics can meet any application requirement.