Electrical resistance measure between phases for a transom mounted hydrogenerator ?

Necessary equipment : 1 multimeter

This electrical resistance measure has to be done with hydrogenerator stopped out of the water.

Step 1 : Check that hydrogenerator is connected to the boat 3-phases line.

Step 2 : Disconnect the 3 phases line at its end, close to the converter.

Step 3 : As there are 4 pins on the connector, one pin of the connector is not connected. Identify the unused pin : its shape is different.

Step 4 : On the 3 other pins used for the 3 phases signal. Measure the resistance (in Ohm) between each pair of phase : 3 phases = 3 measures.

Choose the smaller caliber available on the multimeter - Usually 200Ω -

Keep the value for each pair of phase :

Values should be between 1,3Ω and 2,5Ω.

=> A higher value means there is an issue on the electrical continuity between the generator and converter (damaged cable, corroded or unscrewed...).

=> A low value (<1Ω) means there is a short between 2 phases (sea water in a connector, etc).