Emerson Remote Monitoring Panel Manuale Utente

Inverter Asynchronous

This alarm is triggered by an inverter software routine when the inverter and bypass waveforms 

are misaligned by more than 6 degrees in phase. This alarm resets automatically once the 

condition is no longer true.

1. First check if the alarm “Bypass unable to trace” or “Bypass abnormal” occurs. If so, solve it 

first.

2. Verify the waveform of the bypass voltage. If it is too distorted, ask the customer to verify and 

seek any possible measurements.

Inverter Fault

Inverter output voltage beyond limits. Load transfers to bypass.

Inverter Overtemp.

The temperature of the inverter heat sink is too high to keep inverter running.

This alarm is triggered by the signal from a temperature monitoring thermostat on the inverter 

bridge heat sink.

The UPS will recover automatically after a 5 minute delay from the disappearance of the 

overtemperature signal.

If the overtemperature condition is true, then check for and verify:

1. high ambient air temperature.

2. blocked cooling airway.

3. any fan failure.

4. prolonged inverter overload

Fan Fault

At least one of the cooling fans has failed

Inverter STS Fail

At least one of the static switches of inverter side is open or short circuit. This fault is locked until 

power off.

Bypass STS Fail

At least one of the static switches of bypass side is open or short circuit. This fault is locked until 

power off

Operation Invalid

This record is registered following an incorrect operation:

Output Fuse Fail

At least one of the inverter output fuses is blown. Inverter shuts down. Load transfers to bypass.

Control Power 2 Fail

UPS operates but Redundant Control Power is not available.

Unit Over load

The UPS is confirmed to be overload when the load arises above 105% nominal rating.

The alarm automatically resets once the overload condition is removed.

1. Confirm that the alarm is true by checking the load percent indicated on the LCD panel to 

determine which phase is being overloaded.

2. If the alarm is true, measure the actual output current to verify that the indications are valid.

Disconnect unnecessary load and ensure the safety. In a parallel system, a severe load sharing 

error can also leads to the alarm.

System Over load

The UPS parallel system is confirmed to overload when the total load arises above 105% 

nominal rating for the set basic number of UPSs. The alarm automatically resets once the 

overload condition is removed.

1. Confirm that the alarm is true by checking the system load percent indicated on the LCD 

panel to determine which phase is being overloaded.

2. If the alarm is true, measure the actual output current to verify that the indications are valid.

Disconnect unnecessary load and ensure the safety. In a parallel system, a severe load sharing 

error can also leads to the alarm.

Unit Over load Timeout

The UPS is confirmed to overload and the overload times out.

Note 1: the highest loaded phase will indicate overload timing-out first.

Note 2: When the timer is active then alarm “unit overload” should also be active as the load is 

above nominal.

Note 3: When the timer has expired, the inverter Static Switch is opened and the load 

transferred to bypass. The inverter shutdown and will restart after 10 seconds.

Note 4: If the load decreases lower than 95% after 5 minutes, the system will transfer back to 

inverter mode.

Confirm that the alarm is genuine by checking the load percent indicated on the LCD. If an 

overload is indicated then check the load, and investigate any additional load connected prior to 

the alarm (if applicable).

Byp. Abnormal Shutdown

Both bypass and inverter voltages unavailable. Load interruption

Inverter Over Current

Inverter Pulse Width Modulation module overloaded.