Battery

The MSU has a built in battery that will power it for around 4-8 hours when the power is disconnected. The run time on battery depends on what is switched on (for instance, the floodlights use a lot of battery).

First generation MSUs have a crude battery charging circuit, where the battery is effectively 'float charged' permanently. The problem with this approach is that during sustained periods of heavy discharge (such as when the floodlights are on) the charging input power is not sufficient to keep up with the current draw requested from the battery, resulting in net-discharge.

Low Voltage Shutdown

The low voltage shutdown is a function of the embedded Edge Controller, and as such is subject to the same control logic, resulting in an automatic low voltage shutdown of 10.8V.