Owners Manual

14 © 2015 Sensata Technologies
Installation
amps), and has a time delay that allows for momentary current surges from
the inverter without opening the fuse. In some installations, if the combined
short-circuit current of all the batteries in the bank is determined to be
2,700 amps or less, then an ANL type of fuse may be used—if in doubt, use
a Class-T fuse. See Table 2-2 for the fuse size (coordinated with the DC wire
size) recommended for your CMW inverter.
2.4.3 DC Grounding
The inverter should always be connected to a permanent, grounded
wiring system. The idea is to connect the metallic chassis of the various
enclosures together to have them at the same voltage potential, to reduce
the possibility for electric shock. For most installations, the inverter chassis
and the negative battery conductor are connected to the system’s ground
bond via a safety grounding conductor (bare wire or green insulated wire)
at only one point in the system. The grounding conductor for the DC system
shall meet the sizing requirements specifi ed in the NEC for the application,
but must be no smaller than 8 AWG copper. For instance: An inverter used
in a marine application under ABYC guidelines requires the size of the DC
grounding conductor to be of an ampacity equal to or one size less than that
of the DC positive conductor. See Table 2-2 for the minimum ground wire
size recommended for your inverter.
Info: If the inverter is installed in a vehicle, connect the battery
negative cable directly to the inverter’s negative terminal. DO NOT
connect the negative battery cable meant for the inverter to the
vehicle’s frame/safety ground.
2.4.4 DC Cable Connections
Do not put anything between the battery cable ring lug and the battery
post (see Figure 2-7), or the fl at metal part of the inverter’s DC terminal
(see Figure 2-8). When connecting the battery cable, it should be placed
directly against the battery post or inverter terminal. Incorrectly installed
hardware causes a high resistance connection which could lead to poor
inverter performance, and may melt the cable and terminal connections.
See Table 2-1 for the torque requirements.
Info: The DC terminal and Hex nuts on the CMW1012 and CMW1512
are made of stainless steel, which has a high likelihood of galling or
thread seizing while being tightened—causing the bolts to strip or
to snap/break off. To reduce this risk, use an anti-seize lubricant,
tighten the fasteners slowly (at low rpms) without interruption, and
apply only light pressure.
2.4.5 Wiring the Battery Bank
WARNING: Lethal currents will be present if the positive and
negative cables attached to the battery bank touch each other.
During the installation and wiring process, ensure the cable ends
are insulated or covered to prevent touching/shorting the cables.
Info: DO NOT connect the DC wires from the battery bank to
the inverter until 1) all DC wiring is complete, 2) the correct DC
overcurrent protection has been installed, and 3) the correct DC
voltage and polarity have been verifi ed.