Westerbeke — Checking Exciter Rotor Resistance
Testing & diagnosis · exciter rotor windings
From a Westerbeke service manual covering: WTA 15, WTA 20, WTA 25, WTA12KW, WTA15KW, WTA16KW, WTAl5KW. Check it applies to your exact model before use.
Procedure
- With bridge rectifier still connected, measure resistance between points 1 & 2, 2 & 3, and 3 & 1 (0.7-0.8 ohm).
- If short (0 ohm) or open (infinite) exists, unsolder leads from bridge rectifier.
- Check the windings individually.
Tools required
- ohmmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 0.7-0.8 ohm between points 1-2, 2-3, 3-1
Source: Westerbeke service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.