1. Specification 
JCX-161  BNWAS Installation Manual 
1 
7ZPNA4321 
 
1 Specifications 
1.1 Functions 
The system is a Bridge Navigational Watch Alarm System (BNWAS) consisting of a control unit, a 
display unit, buzzer units, and reset devises. It is designed to prepare for any contingency in 
which a duty officer is disabled to fulfill his duties due to a nap, health problem, or other reason. 
Upon such an event, the system alerts other officers. 
 
1.1.1 Purpose of the system 
The purpose of the Bridge Navigational Watch Alarm System (BNWAS) is to monitor the motions 
of the duty officer in the bridge and detect any his behavior disorder that may lead to a marine 
accident. 
To achieve the purpose, dormant period is set. If no reset operation is performed within the 
dormant period, the system recognizes that the duty officer cannot fulfill his duties and outputs an 
alarm in the bridge. If no response is given even after that, it alerts the captain or other qualified 
officer for its situation. 
 
1.1.2 Operational mode 
BNWAS includes the following operation modes. 
1)  Auto Mode (Automatic mode) 
While the ship's heading control system or the track control system is active, the 
dormant period count down operates automatically. When their systems are not 
activated, the countdown will not operate. 
 
2) Manual On 
     The dormant period countdown operates continuously. 
 
3) Manual Off 
The dormant period countdown does not operate. 
The Manual Off only stops the dormant period countdown. It operates the emergency 
call, other call functions, and the bridge alarm transfer function. 
 
Except in anchorage or in-bay navigation, operate the unit with “Manual On”.