Purpose and Applicable Part/Model Numbers


This guide describes the wiring regime of CXC 120 Facility Site Alarm Cross Connect Cabinet.

Wiring guide

Active Alarm Modules 

There are two versions of the active alarm module r01 and r02. The boards behave slightly differently but this article applies to both. The differences will be explained.

Active alarm modules require no input power in order to monitor the a channel. As a result however they will not work to monitor analog inputs such as  temperature sensors. 

Wiring the inputs 

1. Connect all alarm input connections to your active alarm board inputs. The upper screw terminal is "IN" the lower screw terminal is "+24V". Connect "COM" (Common) connections to the +24V terminal and connect NC/NO connection to the "IN" terminal.  

2. Ensure all devices wired to the active alarm module are not in alarm.

3. Regardless of the input type of the alarm (NO/NC) set the output switch such that the alarm LED is off when no alarm is present.

Wiring the Outputs

Wiring Individually monitored outputs

If the site wants to monitor an input individually with their system this can also be accomplished using the CXC 120. 

1. Wire a cable to the two captive screws on the output relay. This is located just above the switches that set the output relay's state on the right hand side of the board. The upper screw is COM and the lower screw is NC/NO. The state of the output relay can be determined in the way described above in "Programming the Annuciator", or it can be determined with a meter. 

2. Connect this cable directly to the AMU. Connect the COM connection to the "+24V" or "COM" terminals on the AMU. Connect the "NC/NO" connection to the "IN" or "NC/NO" terminal on the AMU. 

Programming the Annuciator  

If you followed the above steps correctly, and if none of the panels are in alarm all the LED's should be off, and;

For r01 boards your output is NO

For r02 boards your output is NC on channel 1-18. Channel 19-24 are NO

You can confirm this with a meter.

1. Following the label on the back of the annuciator, select the channel you would like to program.

2. Select the desired alarm level and set it to NO or NC depending on your output state as described above. Follow the diagram on the back of the annunciator. 

3. As soon as you press "Select" after programming an alarm input it is saved to memory. If you set your output state correctly and programmed the annunciator correctly, the panel will not be in alarm. 

4. To disable an input channel set the switch to "DIS"

Passive Alarm Modules

The passive alarm module is used to monitor alarms with an external power source. The power source can come from the connected device or from the AMU depending on how the system is wired. The passive alarm module can also be used to monitor analog inputs such as a temperature sensor or shunt.  

Wiring a passive alarm module (Alarm Relays) 

1. Connect your alarm input to the input terminal block. The upper connection is NO/NC, the lower connection is COM.  

2. Following the label on the back of the annuciator, select the channel you would like to program.

3. Select the desired alarm level and set it to NO or NC depending on the state of you input alarm. Follow the instructions on the annuciator panel

4. Make sure the jumper above the input is set to normal. 

5. If this input needs to be individually monitored,  wire the AMU to the output terminal block. The Upper connection is COM, the lower connection is NC/NO.

6. To disable a channel, remove the jumper entirely. 

Wiring Analog Inputs

1. Wire the analog input to the passive alarm module input terminal. 

2. Connect the device that will be monitoring the analog input to the output terminal corresponding to the input you just wired.

3. Place the jumper above the input terminal block in the Bypass position. 

Wiring the Summery Alarm Outputs

There are four levels of summery alarm: Critical, Major, Minor and Warning. Each has its own 8p8c modeler jack (RJ45) output. These are intended to allow sites with a limited number of inputs on an alarm monitoring system to monitor summaries of all alarms in a given class instead of each individual alarm.  


1. Wire a Cat-5 cable with an RJ45 to the termination board in the CXC 120. Connect the other end of the cable to the AMU. 

2. The pin out for the 8p8c jack on the CXC 120 is as follows: 

Pin 1: COM

Pin 2: NC

Pin 3: COM

Connect the COM connection to the +24V or COM input on the AMU. Connect the NC/NO connection to the "IN" or "NC/NO" terminal on the AMU. 

GMT Distribution 

Eight GMT fuse positions are provided for powering an Alarm Monitoring Units, Ethernet switchs, or other -48VDC devices. The total current for all ancillary equipment should not exceed 14A.

Refer to the silk screen on the board for polarity information. 

If you are having trouble with this guide, please contact Comm/net Systems Support.

Comm/net Systems Inc. Support


(206) 282-8670

or submit a support ticket through this portal.