4RF Aprisa XE, Руководство пользователя

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Mounting and installing the terminal | 31
External alarms
Two external alarm inputs and four external alarm outputs are provided on the RJ-45 ALARM
connector on the front panel. These enable an internal alarm to provide an external alarm to the
network operator's existing network management system via contact closure or opening, or for an
external alarm to be transported via the radio link.
The latency for an alarm presented on an external alarm input to the alarm being output on an external
alarm output is < 2 seconds.
Alarm outputs are isolated semiconductor relay type contacts rated to 0 to 60 VDC or AC rms with a
maximum current of 100 mA.
Alarm inputs are isolated current detectors with an operating voltage range of 9 to 60 VDC or AC rms
(effective current threshold of 5.0 to 6.5 mA constant current).
The common reference potential for the two external alarm inputs must be applied to pin 3 and the
common reference potential for the four external alarm outputs must be applied to pin 4.
Alarm circuit setup
A typical alarm circuit setup is:
ƒ An external battery applied to the ‘common alarm inputs reference’ and a normally open relay
contact connected to the alarm input. Closing the contact applies the source to the alarm input
detector which turns the alarm on (setup for ‘alarm on when source on’). See “Configuring the
external alarm inputs” on page 74 for the setup options.
ƒ An external earth applied to the ‘common alarm outputs reference’ and a ground contact detector
connected to the alarm output. When the alarm is on (active), the external alarm output relay
contact closes (setup for ‘relay closed when alarm on’). See "
5
Configuring the external alarm
outputs” on page 76 for the setup options.
M
Common alarm
inputs reference
Terminal Terminal
Alarm input
Common alarm
outputs reference
Alarm output
The terminal front panel RJ-45 ALARM connections are:
RJ-45 pin Connection description TIA-568A wire colour
1 External alarm input 1 green / white
2 External alarm input 2 green
3 Common reference for alarm inputs 1 to 2 orange / white
4 Common reference for alarm outputs 1 to 4 blue
5 External alarm output 1 blue / white
6 External alarm output 2 orange
7 External alarm output 3 brown / white
8 External alarm output 4 brown