Forums » Ask a Question

Use this forum to post your questions to our experts – you need to be logged on to do it (you can register here ), then scroll down to the bottom of this page and click the blue Post Thread words

If you can help answer the question, feel free to post a reply – you need to be logged on to do it (you can register here ), then hit the reply button on the thread.


To go back to the experts page click here>>


Posted: Tue Sep 07, 2010 7:47am

Post Subject: battery charging rate

on initial start up my alternator delivers about 30 amps but after about 5 minutes this falls back to about 5 or 6 = this occurs with both batteries (manual switch)this would be ok if they were fully charged but my inverter alarm tells me the domestic bank hasnt enough charge to run it. Im sure i read somewhere that the alternator could be tricked into delivering more power by adding a few diodes,do you know anything about this? If not what are my other options = regards bob


Posted: Tue Sep 07, 2010 8:29am

Post Subject: battery charging rate

Yes, I do know about it. Do a search on the Canal World Forum ( However from the very sparse details you give I suspect one of the following: a battery problem, an alternator problem, or a wiring problem. Unless this boat/engine is well over 20 years old I would expect the alternator to deliver far more than 30 amps on startup but without the data for your alternator I can not be sure. With a manual switch and only 30 amps output with an inverter I also suspect your domestic bank may be ruined. I need a lot more information about your system to say more. I would like to know the battery terminal voltage when you first get on the boat, after the batteries have rested for many hours. I doubt adding the diodes (if it is possible in your case) will solve this problem. Tony Brooks.

Most Read

Newsletter Sign Up

Canal Boat monthly newsletter
Sign up to receive our regular email newsletter

Our Privacy Policy

Like us on Facebook

Follow us on Twitter

Cache: Disabled for this object  Total Queries: 43.  Total Objects: 162.  Total Unserialized: 3. Total Runtime: 0.32 seconds.