Anode question

[SailorSam]

Just checked my anodes on a twin duo prop setup. One ring anode is well eaten after 7 months, the one on the other leg is like new. No sign of decay on the leg. Any ideas?

 

[mandlmaunder]

Check out your dock for voltage leak or your neighbour for charge leak.
Just a guess that your boat is in a marina /forums/images/graemlins/ooo.gif

 

[ShaunG]

If its wearing away its doing its job. As for the reason that only 1 is wearing and the other is ok, check the internal bonding, you may find that 1 is bonded to the DC and/or the AC system and the other is only protecting the leg and is not bonded to any other circuit or part of the boat, or the anode that is in good condition has a higher resistance on the bonding cable

 

[SailorSam]

Boat is on a pontoon but no shore power connections.

 

[hlb]

I'd worry about the one not eaten.

 

[MaltaBob]

Another possibility is that the anodes are 'similiar' but produced from different materials! Lots of dodgy parts around these days ?
Have seen some imitations that just don't work, but look and feel like the real thing. /forums/images/graemlins/frown.gif

 

[mont]

Must assume ...
1. Both ring Anodes are same material ?
2. Both Anodes are compatable to water conditions - salt , fresh, brackish. ?
3. Both anodes are well connected / bonded / grounded to each leg. No antifoul or paint behind before they were fitted - common lazy problem. ?
4. The other anodes on the suspect leg show erosion also. ?
5. You have also had fitted / are fitted the two triangular anodes on the main wishbone / h frame - this help spread the protection. ?
6. A check of earthing with a simple meter shows correct - covered in MBM a few months ago. ?
Hope this helps ....