120VAC, 60Hz
System Controller
Water heater
Terminals
(Units 1 - 24)
Remote Controller Cord
Remote Controller Cord
Remote Controller Cord
Remote Controller Cord
terminal block
Remote Controller Cord
terminal block
Remote Controller Cord
terminal block
PCB
Power
PCB
PCB
Power
PCB
PCB
Power
PCB
Remote Controller Cord
Remote
Controller
System Controller
power supply
* The power cord is not supplied with System Controller.
(For procedure of connecting the power cord, refer to “Procedure of connecting
the power cord to System Controller” sheet stuck into the system Controller.)
Unit 1
Unit 2
Unit 3
Main
Controller
Power
PCB
Sub Controller
1
Sub Controller
2
Sub Controller
3
Sub Controller
4
Disconnect this
Connector
Disconnect for
system controller
NC380-SV-ASME only
* This connector must
be disconnected in
each unit.
CAUTION
• The below diagram shows the connection of 3 units to the system controller.
When connecting 4 or more units, follow the same procedure.
• Connect the water heaters to the system controller following the detailed wiring instructions
included with the system controller.
• Always connect a remote controller to the system controller.
* The remote controller terminal location
may differ depending on the unit.
5. Wiring Diagram
─7─