4
2.3
DC Input Connections
Before making any of the DC output connections, make sure you read and fully understand the DC Connection
Procedure on the following page. Select proper size for the DC wires using the table below. Refer to Appendix A
for the DC input current draws at full load capacity. This is
based on an overload
current of 110-115%
of the
input current listed on the inverter nameplate. If the distance between the
inverter’s DC in
put and the battery
exceeds 10 feet, use the Power Wiring Guide in Appendix B to minimize the voltage drop across the wire distance.
WARNING:
Before beginning any work inside the inverter, ensure that all incoming AC/DC power is
de-energized and/or isolated. Verify that no voltage is present inside the case by using a voltmeter at
all input and output terminals. Assure the inverter that is being used is the same number and type of
cell as the inverter front nameplate specifications.
The FT inverter DC terminal bolts accept a 5/16”
or M8 ring terminal stud size.
NOTE:
It is recommended to use a battery disconnect breaker between inverter and battery bank; helpful during
battery or inverter maintenance. The breaker/disconnect should be sized with consideration of the full load DC
input current of the inverter. Refer to Appendix A for the DC input current draws at full load capacity.
Breaker Size/
Fuse Size (Amps)
Minimum AC/DC Wire
Size Requirement
Equipment Grounding
Conductor Minimum
25
#10
#12
30
#10
#10
40
#8
#10
50
#8
#10
60
#6
#10
70
#6
#8
80
#4
#8
90
#4
#8
100
#4
#8
125
#2
#6
150
#1
#6
175
#1/0
#6
200
#2/0
#6
250
#4/0
#4
300
250 MCM
#4
Table 2
–
AC/DC & Ground Wire Size Minimum Requirements
(All wires specified in the table are rated at 90 °C or 194 °F)
NOTE:
These are recommended sizes per La Marche Standards. The National Electrical Code (NEC) and Local
Wiring Codes must be followed.
DC Connection Procedure
The battery connections should be done in the following order:
1.
Assure that the incoming AC mains input power to the inverter is turned off.
2.
Check polarity of DC input cables and verify with multimeter.
3.
Connect the positive DC input cable to the positive terminal and the negative DC input cable to the
negative terminal.
OBSERVE PROPER POLARITY
.
