NewMar Power System Manual
M-CMDRII 063022
Page 21 of 43
Model: COMMANDER II AND COMMANDER II+
Version 1.0
Relay 3 Critical alarms
Red LED
Relay 4 Spare
Relay 5 Spare
Relay 6 Spare
Buzzer
Red LED
7.4.3
EM4x Main PCB Digital Input Alarm Mappings
General purpose inputs allow the Commander II & II+ system to monitor any external equipment that includes
relay or auxiliary outputs. The GPIP inputs are activated by connecting the system positive (common) to the
input terminal (configuration setup in the EM4x can allow activation by connecting to system live).
General purpose inputs can also be configured as analogue inputs for purposes such as battery midpoint
monitoring and voltage monitoring.
These inputs may be assigned to contribute to alarm states within the monitor. The state mapping is defined
in the configuration file. Alarm mapping should be completed using the EM4x software. Please refer to the
EM4x manual for detailed information.
The inputs are normally activated by connecting system positive (usually system common) to the input.
7.4.4
Circuit Breaker Fail Monitoring
Comment:
Main circuit breakers (MCBs) are monitored electronically via a diode to a digital input on the EM4x.
The digital input will trigger an alarm when it is pulled to the system common (positive) rail. The Breaker Fail
alarm will only operate if a load is connected to the output to provide a return circuit for the sense wire.
Therefore, for breakers that do not have a load connected, the breaker can remain in an OFF position without
causing a false alarm.
The battery circuit-breakers, however, use voltage sense to detect tripping or whether they are turned off. This
is because when a battery breaker is tripped, there may be very little voltage difference across the breaker,
making electronic fail detection problematic. Hence, if no battery is connected, the breaker must be ON to
clear the Battery Breaker Fail alarm.
8
LVD
OPERATION
The primary Low Voltage Disconnect contactor is located in the battery side of the DC distribution. A
secondary Load Low Voltage Disconnect can be optionally included in a section of the load side of the DC
distribution.
The LVD contactor is a bi-stable, magnetically latching contactor. This means that failure of power or removal
of the EM4x from a live system will not cause the contactor to change state. Periodic pulsing of the LVD
control signal allows the monitor to ensure the contactor remains in the correct state. The contactor is
monitored by the EM4xto allow an alarm to be generated when the contactor is open.
The EM4x energy manager unit is powered from both the rectifier side of the LVD contactor and direct from
the battery source. Following an extended AC outage and the low output voltage threshold being reached, the
primary LVD disconnects the battery from the system live bus and the EM4x will lose voltage sense (as voltage
sense is measuring system live bus voltage) yet still maintains operation for system monitoring. The LVD
contactor will not re-engage until rectifier input supply is restored (i.e., until the DC bus voltage is re-
established). LVD adjustments/settings are all made in the supervisory module.
9
M
AINTENANCE
As NewMar power systems are state of the art electronic systems, little routine maintenance is required.
