Black Box ServSensor JR EME102A, Руководство пользователя, Страница: 40 / 135

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ServSensor JR
38
2.1.8 DRY C
ONTACT
S
ENSOR
The Dry Contact sensor is a simple connection to burglar alarms, fire
alarms or any application that requires monitoring by the ServSensor
JR.
These general-purpose switches can be either input or output. When
used as an output it can source up to 20mA. You can select the output
voltage by setting the Output Level to a Low or a High. When set to
Low the pin will output 0 volts. When set as a High the pin will output
5 volts.
When used as an input a switch will retain any error condition until it is
read via SNMP. Therefore if a switch encounters a critical condition at
any time it must report that condition before it can return to a normal
state.
Input pins can be used to detect whether or not an input switch is open
or closed. In combination with external sensors, input pins can detect
whether a door or window is open or closed, if there is a water
incursion and many other conditions.
The input pins work by sensing the presence of a voltage level on an
input pin. When the switch is open the voltage is different than when
the switch is closed.
To test a dry contact input, wire ground to one side of the switch.
Ground is always pin 8 on the connector. Wire the other side of the
switch to the switch sensor. Set the
“NormalState” to High. Set the
“Direction” to Input. When the switch closes the input pin will be
shorted to ground and the switch will change state from normal to
critical
Specifications & Features:
•
Measurement Indication - Alarm or Normal
•
Communications cable - RJ45 jack to sensor using UTP Cat 5
wire.