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2) Run a power cable thru the grommet (located at the bottom of the base unit), and connect the
cable wires to their corresponding power terminals
Component
Marking
on board
Function
Recommended cable
Power terminals
(Thread size: M3)
P
Polarity:
＋
Power input (24 VDC)
2-core CVV cable
N
Polarity:
－
Power input (24 VDC)
Single-point grounding (grounding at a single point) is mandatory. When the
cable shield from the gas detector is grounded on the power supply side, DO
NOT ground the shielded cable to the Earth terminal located inside the gas
detector (on the terminal block for power cable) to avoid 2-point grounding.
If used in a place exposed to electrical noises, use a shielded twisted pair (STP)
cable. When using STP cable, provide signal grounding so that all the
connected devices are ground-looped (ground continuity) to avoid noise
interference due to ground discontinuity.
Set the terminal resistor switch (located on the base unit) to the ON position
when terminal resistors are used at both ends of the circuit.
3) Perform the communication setup (select the “RS485” mode and set the unit ID with the DIP
switches (mode change switch and address setting switches). Refer to pages 19 and 20 for the
procedure).
4) Set the base unit power switch to the ON position.
NOTE
Power terminals
