Micro
ARE Series 24V Chargers, Single Phase
Options and Accessories
PM990-1070-24, Issue 12
7-3
Output MOVs
7.3
The output MOVs protect the charger from externally created voltage transients. The MOVs are
connected from each output pole of the charger to the cabinet (earth). If an excessive transient enters the
unit on the output cables, the MOVs clamp the voltage to an acceptable level. Repetitive clamping of
transients and clamping high energy transients will degrade the MOVs requiring eventual replacement.
Drip Shield
7.4
The drip shield is intended to prevent water from dripping into the unit from the overhead structure
indoors. When used, nothing should be set on the perforated top screen of the charger or the drip shield.
Placing anything on the top screen may create a fire hazard. When the drip shield is used, personnel
should avoid contact with the perforated top screen.
Temperature Sensor
7.5
The temperature sensor is connected to J2 on the interface board as shown in Figure 2-6 and described in
Section 2.4.7. This is required for battery temperature compensation and to annunciate a high battery
temperature alarm.
Ground Detection Switch
7.6
The Ground Detection Switch is a factory-installed option that allows the operator to easily disable the
ground detection by breaking the internal connection from the internal detection system and ground.
Breaking the internal ground connection is useful for troubleshooting ground paths on the dc system or
eliminating interactions with other ground detection equipment on the system.
Unless other ground detection is in use on the DC system, the ground detection switch should be left in
the ON position.
DNP3 Communications
7.7
This allows the charger to be controlled and monitored from a remote location over a 10/100Mbit
Ethernet network connection using the popular DNP3 protocol. More information about this protocol can
be found at http://www.dnp.org. The DNP3 device profile (PM990.1072.00) and installation guide
(PM990.1074.00) can be found on UNIPOWER’s web site at http://www.unipowerco.com.
High interrupt AC breakers
7.8
This option gives the charger an enhanced AC line current interrupting rating of at least 10,000 Amps.
