Installation Manual

Operation

3.6 Protection Circuitry Operation

The inverter is protected against fault conditions, and in normal usage it will be rare to see any.

However, if a condition occurs that is outside the inverter’s normal operating parameters, it will

shut down and attempt to protect itself, the battery bank, and your AC loads. If there is a condition

that causes the inverter to shut down, it may be one of the following conditions [also refer to the

Troubleshooting section (Section 4.3) to help diagnose and clear the fault condition]:

• Low Battery – The inverter shuts off whenever the battery voltage falls to the LBCO (Low

Battery Cut Out) level—to protect the batteries from being over-discharged. After the inverter

has reached the LBCO level and turns off, it automatically restarts after one of the following

conditions are met:

1. AC Power is applied and the inverter begins operating as a battery charger.

2. Battery voltage rises to the LBCI (Low Battery Cut In) level.

Refer to Table 3-1 to determine the LBCO and LBCI levels for your inverter model.

• High Battery – In the event the battery voltage approaches the HBCO (High Battery Cut

Out) level, the inverter automatically shuts down to prevent it from supplying unregulated

AC output voltage. The inverter’s status LED turns off when a high battery fault condition

occurs. The inverter automatically restarts when the battery falls to the HBCI (High Battery

Cut In) level. Refer to Table 3-1 to determine the HBCO and HBCI levels for your inverter.

Info: High battery voltage may be caused by excessive or unregulated voltage from the

external charging sources.

• Overload – During inverter and standby operation, the inverter monitors the DC and AC

current levels. In the event of a short-circuit or an overload condition for more than a few

seconds, the inverter shuts down. To start operating after this fault, the inverter needs to be

restarted (turned back on) once the inverter’s AC loads are reduced/removed.

• Over-temperature – If internal power components begin to exceed their safe operating

temperature level, the inverter shuts down to protect itself from damage. The inverter’s status

LED turns off to indicate the over-temperature fault condition. The inverter automatically

restarts after the units cool down.

• Internal Fault – The inverter continually monitors several internal components and the

processor communications. If a condition occurs that does not allow proper internal operation,

the inverter shuts down to protect itself and the connected loads. The inverter needs to be

reset to start operating—refer to Section 4.4 for information on resetting the inverter.

Table 3-1, Inverter Battery Turn On/Off Levels

Inverter battery turn

ON/OFF Levels

Inverter Model

ME2000/ME2012 ME2512 ME3112

HBCO >15.8 VDC >15.8 VDC >15.8 VDC

HBCI 15.5 VDC 15.5 VDC 15.5 VDC

LBCI ≥12.5 VDC ≥12.5 VDC ≥12.5 VDC

LBCO

(1-minute delay)

10.0 VDC* 10.0 VDC* 10.0 VDC*

LBCO (immediate) 8.5 VDC 8.5 VDC 8.5 VDC

*adjustable from 9.0-12.2 VDC with a remote control