Attribute: Sector limit one

Acronym: SECTR1

Code: 136

Attribute type: F


A sector is the part of a circle between two straight lines drawn from the centre to the circumfe rence. (Advanced Learner's Dictionary, 2nd Edition)

Sector limit 1 specifies the first limit of the sector. The order of sector limit 1 and sector limit 2 i s clockwise around the central object (e.g. a light).

ENC Condition:

# Must be encoded for LIGHTS objects that are sector lights.


INT 1: IP 40;

S-4: 475; 475.1;

Minimum Value: 0

Maximum Value: 360


Unit: degree ()

Resolution: 0.01 degree

Conversion factor: one tenth of a second = 0.000028 degree.




125 for a sector orientation of 125 degrees.


The values given to the common limits of adjacent sectors should be identical.

The orientation of bearing is from seaward to the central object. This conforms with the method used in 'List of Lights' publications.

A generic term such as 'to shore' cannot be used; a specific bearing must be encoded. Where a light sector limit is defined as 'to the shore', it should be encoded using a value that ensures that, when the limit is drawn, it will fall entirely on land.