AC Module System Installation Manual
Rev. 1.0
44
Copyright © 2017 LG Electronics.
All Rights Reserved.
3-13 Grid Voltage Measurement
AC junction box
An array of AC modules
Meter
N L1 L2
G
Distribution panel
Measure AC voltage of the utility at the distribution panel and AC junction box using a volt-
meter. Fill out the below table. If the measured voltage is out of the range which is specified in
each table, then ask to local electricity provider for voltage instability.
Measure point
Single Phase 240V(RMS)
Single Phase 208V(RMS)
Three Phase 208V(RMS)
Merge, Split Type
Expected
Range
Measured
Expected
Range
Measured
Expected
Range
Measured
L1 – N
120
106~132
120
106~132
120
106~132
L2 – N
120
106~132
120
106~132
120
106~132
L3 – N
-
-
120
106~132
L1 – L2
240
211~264
208
183~229
208
183~229
L2 – L3
-
208
183~229
L3 – L1
-
208
183~229
Measure point
Single Phase 240V(RMS)
Single Phase 208V(RMS)
Three Phase 208V(RMS)
Merge, Split Type
Expected
Range
Measured
Expected
Range
Measured
Expected
Range
Measured
L1 – N
120
106~132
120
106~132
120
106~132
L2 – N
120
106~132
120
106~132
120
106~132
L3 – N
-
-
120
106~132
L1 – L2
240
211~264
208
183~229
208
183~229
L2 – L3
-
208
183~229
L3 – L1
-
208
183~229
At distribution panel
At AC junction box
Voltage
measure
•
Plan the installation work in moderate weather. There is a risk of electric shock when it is raining
or snowing.
•
To prevent the risk of accidents, use proper PPE (Personnel Protective Equipment) including
helmets and globes at all times.
•
If installation location is high above ground, make sure to use Fall Protection System during the
installation.
•
For safety, only qualified personnel should service the work.
Leave the transition
cable disconnected