enphase IQ System Controller 3M Quick Install Manual page 23

Section C - Wiring
Aux wiring: System Shutdown Switch
Wiring test for SSD Switch in the OFF position
a. Ensure the SSD Switch is in the OFF position.
b. Ensure the IQ System Controller is powered ON from any of the sources.
c. Set the multimeter to measure the DC voltage.
d. Measure the terminal test points:
• 1 and 2 at the SSD Switch
• 1 and 2 at the SSD header
• 3 and 4 at the SSD Switch
• 3 and 4 at the SSD header
The multimeter should show a value between 2.7 VDC to 3.3 VDC in all cases.
e. Verify the connections and rewire them if needed.
IQ System Controller 3M quick install guide 23