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4
Structure and functions
NK8237 hardware
20
Building Technologies
A6V10854379_a_en
CPS Fire Safety
30.11.2017
1
2
3
X1
X2
X3
X101
X102
X103
X104
X105
X111
4
Internal DIP switch and jumpers (NKM8001-A2 mainboard)
Item
Name
Description
1
S101
DIP-Switches
2
S1
Reset button
3
S2
Tamper switch
4
X115
When closed, it disables the box tamper alarm.
6.1.4
Serial interfaces
The NK8237.2 model is equipped with two serial lines available on the main board.
The serial port can be configured as an RS232 interface using connector COM1
and COM2, or as an RS485 interface using connectors X104 and X105.
All lines are fully RS232 compliant and have EMC/ESD protection.
No galvanic isolation is provided; all serial lines have a common ground.
6.1.5
Onboard I/O
The NK823x main board is equipped with three digital inputs (X102) and one relay
output (X101).
The relay output can be used for reporting a faulty communication detected by a
watchdog timeout expiration (see General gateway parameters [➙ 59]).