The following blinking light patterns/codes are typical codes appearing on the MM or MMS inverters or the MM-RC remote. Always refer to your full owner's manual for complete information.
| Fault Code | Cause | Possible Solution |
|---|---|---|
| 1 blink Once every four seconds |
The inverter has detected a battery voltage below the Low Battery Cut Out (LBCO) setpoint. | 1. Connect AC source (grid or generator) to inverter/charger's AC input to charge the batteries. Fault will automatically clear when the battery voltage increases to 12.5V (12V system), 25.0V (24V system), 50.0V (48V system). 2. If the battery voltage is above critical low battery (9V on a 12V system, 18V on a 24V system, 36V on a 48V system), the fault can be cleared by performing a soft reset. Press the inverter on/off pushbutton to turn the inverter back on. |
| 2 blinks Twice every four seconds |
The inverter has detected battery voltage greater than the High Battery Cut Out set point (>16.0 V on 12-volt ME/RD models, >16.9V on 12-volt MS models, >32.0V on 24-volt ME/RD models, >33.8V on 24-volt MS models, >67.6V on 48V models) | 1. Check battery wiring to make sure it is properly wired for the inverter (12V/24V/48V nominal). 2. Disconnect external charging sources that could be causing battery voltage to increase higher than it should. |
| 3 blinks Three times every four seconds |
The inverter has detected that the FETs (Field Effect Transistor) and/or transformer inside have exceeded their operating temperature (Transformer > 117C/243F, FETs > 90C/194F). | 1. Reduce loads on the AC output if inverting, or lower charge rate if charging the batteries. Once temperature is reduced, the unit will automatically restart. 2. Ensure the inverter is not in a hot area and has proper ventilation. Once temperature is reduced, the unit will automatically restart. 3. Check that the internal fans are running. If the Tfmer/Xfm (transformer) or FET temperatures are above 60°C/140°F and the fans are not running, contact an authorized service center for repair. 4. If internal reading shows 151°C/303°F, this indicates a thermistor has shorted and the unit will need to be repaired. Contact an authorized service center for repair. |
| 4 blinks Four times every four seconds |
The inverter has detected a load on the AC output that is larger than its capacity. | 1. Remove excessive AC loads from the inverter output. Perform a soft reset and press the inverter on/off pushbutton to turn the inverter back on. 2. Check for wiring shorts on the AC output by disconnecting all loads. Perform a soft reset and press the inverter on/off pushbutton to turn the inverter back on. 3. Check if the AC output wires are incorrectly wired. Correct wiring as needed. Perform a soft reset and press the inverter on/off pushbutton to turn the inverter back on. |
| 5 blinks Five times every four seconds |
Internal Fault - The inverter has detected a problem that is not one of the other four faults described above. | Perform a hard reset of the inverter. If the internal fault remains or returns, the inverter will require repair at an authorized service center. |