Mast cable colours, functions and terminals

Tests

Wind speed

The following test can be used to simulate the windspeed readings from a masthead unit sensor.

1. Locate the masthead unit cable junction box at the base of the mast.
2. Disconnect the masthead unit wires in the junction box.
3. Identify which masthead unit cable goes back to the wind display or processor.
4. Carefully isolate the Windspeed wire (normally Violet) and the 0V supply wire (normally Black).
5. Quickly tap the windspeed wire to the 0V wire. This will now simulate windspeed. The faster the two wires are tapped together, the faster the windspeed reading will be.

If your display starts to show windspeed readings when this test is performed, the problem is located somewhere up the mast. The most likely cause is a faulty masthead sensor. If this is the case, the masthead unit should be returned to your local authorised B&G Dealer for further testing. Another possible cause for no windspeed readings is a broken or short-circuits in the sensor mast cable.

If your display does not show windspeed readings when this test is performed, then the problem is most likely with the display or control unit.

Wind angle

1. Locate the masthead unit cable junction box at the base of the mast.
2. With the system switched on, and using a Digital Volt Meter, measure the wind angle phase voltages, normally Red, Green and Blue, with respect to 0V (normally Black). The measured voltages can be anywhere between 0.1V and 6.4V and will vary dependent upon the wind angle.

If any of the phases are “stuck” on one particular voltage, or the variation is minimal, then the problem is most likely to be a faulty masthead unit sensor. Alternatively, if the sensor proves to be OK, then a damaged mast cable may be the problem.

Voltage measurements