Toshiba BMS-IFDD02E2, Installation Manual

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6
If an inductive load (relay coil) or a bulb is connected, a surge voltage or rush current will be
generated. Take adequate measures against surge voltage or rush current.
CAUTION
Wiring Connection
The following describes wiring connections of the Digital Input/Output Relay Interface when it is used in
the air conditioner control system.
• Terminator resistor setting
Set the RS-485 terminator resistor by the TCS-NET Relay Interface.
Do not set it by the Digital Input/Output Relay Interface.
• Shield earthing
The shield earth of the RS-485 signal wires should be single-point earth. Earth the wires on the Touch
Screen Controller.
Other shield lines should be closed, and the terminal end should be open and insulated.
• Connection of external digital inputs
Input circuit examples are shown below (electrically isolated using a photo-coupler).
(1) Example of contact input connection
12V
12V
(2) Example of current sink connection
• Connection of external digital outputs
Output circuit examples are shown below (open collector output electrically isolated using a photo-
coupler).
(1) Example of load connection
(2) Example of load connection
12V
GND
12V
+12V
Connection of Power cables/Earth wires/
2
Signal wires
(continued)
Contact
Input terminal
DI-1 to DI-8
Current sink
Input terminal
DI-1 to DI-8
Output terminal
DO1 to DO4
Load
External
power
supply
Output terminal
DO1 to DO4