The MB4102 / MB4104 Power station will not charge from mains

Symptoms of this issue

The MB4102 2000W / MB4104 2500W power stations will not charge from mains. You may find the display will light up only briefly when you press the power button to turn the unit on. It may also display a message E024.

Cause

These power stations have a battery protection mode that will activate if you drain them too far. Units that are stored away with low state of charge, or run until completely discharged, may enter this protection mode to prevent damage to the battery. As with any Lithium battery, it's best not to discharge them below 10%.

How to fix

Reset the circuit breaker - disconnect all cables, and press the button below the mains input socket.

If this does not help, apply at least 50v DC to the DC Input (red/black ports on the side above the mains input) from a solar panel or connected series of solar panels for a while (make sure it receives no more than 80v DC). A lab power supply capable of 50v DC or four 12v batteries in series can also do this. Red plug is positive, black plug is negative.

This should only need to be applied for a minute or two, then plug in the mains cable. This will reset the protection mode and the unit can then be charged from mains power. 

If you plan on storing the units away for some time, please make sure they have at least 60% charge, and are checked and recharged every six months.