Checking the diodes

CHECKING THE DIODES

Checking the excitation diodes

Place an ohmmeter lead in contact with the blade (1) which touches the positive brush.

The instrument’s second lead should be placed in contact with each of the three terminals (D–E–F) in turn.

Repeat the three measurements after reversing the connections of the instrument’s leads.

Checking positive power diodes

Place an ohmmeter lead in contact with the positive diode pack (2).

The instrument’s second lead should be placed in contact with each of the three terminals (D–E–F) in turn.

Repeat the three measurements after reversing the connections on the instrument’s leads.

Checking negative power diodes

Place an ohmmeter lead in contact with the negative diode pack (3).

The instrument’s second lead should be placed in contact with each of the three terminals (D–E–F) in turn.

Repeat the three measurements after reversing the connections of the instrument’s leads.