First, do not worry about your instruments. Modern sailing instruments are designed to run on normal system voltages from 10 to 30 volts and will have no problem with running off the 24V side of the Amel electrical system--unless your charging system is seriously out of whack.
As I upgrade my instruments from the 70’s era “vintage” models, fewer and fewer things are connected to the 12V converters. Remember, those converters were installed because 24 volt instruments of a quality that Amel wanted were not available back in the mid 70’s when 24 volts boats were much rarer than then are today. They are never quite going to go away, because I still need a 12V source for my NMEA2000 network backbone, if for nothing else.
There is one place where the converter is a great solution: running an SSB off it’s own dedicated converter. Boats with 12 Volt only systems can have a lot of trouble keeping the voltage up high enough (13.4V) to properly drive an SSB during transmissions without a charging source running. That big converter makes our SSB installations work better than a lot of other boats.
If you have batteries that require occasional high voltage equalization, it is just good practice to turn everything off while that process is going on, including your 24 to 12 volt converters.
Not all Amel’s have the navigation lights run off the converter. Mine does not. They have always run directly off 24 volts, and work fine.
To be honest, I am mystified why anybody would still be fussing with incandescent lamps on the top of the mast. For me at least, the hassle of changing a masthead light is well worth the cost and effort of a well made, internally voltage stabilized, waterproof, LED fixture. Even if I wasn’t concerned about power draw at all, (and I am!) the mast head would be an LED fixture. It is mature technology these days, and well made ones do not require separate, external, voltage regulators.
SM #160, Harmonie
Newport, RI, USA
“Ships and men rot in port."
I have had all new instruments installed on my boat . Without being consulted the electrician removed the 24 to 12v converter next to the head and installed 24v bulbs in mast head fixture. Thinking it was something the previous owner installed , I did not object , not knowing it stabilized the current as well as converted it. From the beginning , Joel advised me not to change things electrically, I value his opinions and tried to follow them. When I brought this up to the electrician , he asked me why all boats don't have a stabilizer if necessary. I want to discuss this further with him , but how do I answer the logical question . Other boats have generators and engines that increase voltage , how is that they don't require a stabilizer ? Secondly , they powered all my new instruments with 24v . Are they going to be prone to failure ? I want to have any changes done , if necessary before getting my boat back within the next week or so.
From: Kent Robertson karkauai@...
To: amelyachtowners <amelyachtowners@...
Sent: Wed, Sep 7, 2016 8:33 pm
Subject: Re: [Amel Yacht Owners] Masthead lights do not last
I believe that the charging voltage is, 28.8 absorption and 32+ equalization, transmitted to the Masthead lights.
No I don't think so....you can't get voltage surges with a big battery bank.
IF it could possibly happen you'd be having all sorts of issues with lamps and other 24VDC devices.
The ONLY way you MIGHT have an issue with this would be if you used the EQUALISE cycle on your battery charger while the masthead light was on. The EQUALISE cycle raises the voltage to around 32VDC for a while, but that is something you would rarely do, possibly only if you had flooded batteries that you suspected of being sulphated, and if you know about equalising batteries, you would also know to turn off anything on the DC circuit before starting to do it.
Its much more likely that you have bad connections, salt water ingress into the lamp holder.....