Chapter 3  INSTALLATION OF THE DISPLAY UNIT 
3.11  CONNECTING CONTACT SIGNALS TO EXTERNAL BUZZERS/EXTERNAL DEVICES 
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3 
 NSTALLATION MANUAL
3.11 CONNECTING CONTACT SIGNALS TO 
EXTERNAL BUZZERS/EXTERNAL DEVICES 
 
This equipment has the dry contact output that outputs external buzzer and alarm status 
as contact signals. 
Dry contacts are output from pins 6 and 7 of the 8-pin connector of J5. 
 
Reference: 
The capacity of the output contacts is up to 1A/30V. 
When a larger current/voltage is applied, install an external device with a sufficient contact 
capacity such as a relay. 
When the current/voltage exceeded the contact capacity, the contact of this equipment is 
fused and external buzzer is emitted continuously, causing an extremely dangerous 
condition. 
 
 Connecting contact signals to external buzzers/external devices 
When connecting an external buzzer to this radar, connect the necessary signal line to the 
attached NMEA data connector P5 (for J5) using the following diagram as the reference. 
JMA-3300 side  External buzzer side 
⑥ALM+ 
Dry contact output 1 
⑦ALM- 
Dry contact output 2 
 
 HDG connector (J5) 
 
To GPS or NMEA equipment 
①NSKTX+  :Sending signals + to HDG 
②NSKTX-  :Sending signals - to HDG 
③NSKRX+  :Receiving signals + from HDG 
④NSKRX-  :Receiving signals - from HDG 
⑤GND  :Power GND for NSK 
⑥ALM+  :Dry contact output 1 
⑦ALM-  :Dry contact output 2 
⑧+5V  :Power for NSK (+5V)