Replace Soderberg Chart Light

[GJD]

Hey Guys, Can a Soderberg chart light (32V) be replaced with a 12 or 24V light? (elementary question, but I'm no electrician)

Thanks a lot.

 

[MikeP]

I assume you mean you want to change the bulb and then connect the light to a 12v or 24v power source. If so, the wiring may not be large enough to carry the 12v. I don't know the bulb's wattage but it isn't particularly bright so it may not really need a larger wire size - you could calculate it. Just determine the power demand for the 32v light bulb (how many watts does it need,) convert to amps and multiply it by 2.6. Then determine the wire size needed for that power draw and compare that with the actual wire size in the light fixture. http://bluesea.com/viewresource/529

If the numbers don't work out, you could rewire the fixture itself with larger wire OR, much easier if you have money to burn - just buy one in 12v or 24v: http://www.landfallnavigation.com/-ncl12.html

On our 53, other than turning it on to see it work, I have never used the light for anything but it looks cool! Is it working? If so, why not just leave it alone?

 

[GJD]

Thanks Mike - Actually the bulb's fine. The wires are pretty worn out. I do like using it when powering down the boat at night (salon's usually dark and I operate from the bridge). Guess my question is if I purchase a new 12 or 24V chart light (one that is brighter) would those hook straight up to the existing 32V leads that service the existing fixture?

BTW - helluva calculation!

 

[MikeP]

NO! If you buy a 12 or 24 v unit or bulb, and connect it to the 32v power, it will blow out - the 12 will blow in a few seconds. The 24 might make several minutes. The power supply (voltage) has to match the bulb and wiring.

You can always use existing 12v wiring if you want to switch to higher voltage but you can't go the other way unless you check the existing wiring's ampacity first to be sure it's OK.

 

[GJD]

Gotcha. So another newbie question then - why are our boats wired 32 when 12 and 24 seems so much more prevalant?

 

[Brian Degulis]

Gotcha. So another newbie question then - why are our boats wired 32 when 12 and 24 seems so much more prevalant?

Because raising the voltage from 12 to 32 lowers the amperage required to power things. When you lower the amperage you can use smaller wire the wattage or total electrical power remains the same but the wiring and even the equiptment itself doesn't have to be as large.

The problem with 32V is that it's obselete 24V is much more common.

If you get a 12 or 24V chart light and go to an electronics supply they can set you up with a resistor that will lower the voltage but it must be matched to the light. Or re wire it to your 12V electronics circuit.

Brian

 

[MikeP]

32v may be obselete in boats but I have had no trouble getting any components - and would never consider revising the voltage in out Hatt. true, you won't find 32v items at west marine but you wont find 24v there either. 32v is used a lot for remote power (solar, wind, etc) so it's not really as "obselete" as it sounds. The Outback 3232 inverter is an absolutely superb unit for these Hatts and their 32v system.(3200W/32v). They exist because of the fairly common use of 32v in offline power.

 

[Brian Degulis]

I'm not sure but I don't think you will find anything system built today using 32V. The outback inverters are great I have one also but I think they are available for existing systems just like all the other 32V stuff. Obsolete doesn't mean bad are 2 cycle Detroits are obsolete also but you can have problems and aditional expense getting components.

I just had to replace a blower 24V is readily available but jabsco no longer makes 32V so the motor has to be custom made or modified. I can't get an electronic bilge pump and I can't get 8V AGM batteries along with lot's of other things no longer available in 32V. It works fine but availability is a problem that will only get worse.

Brian

 

[SKYCHENEY]

You can buy a new chart light that is 12v and just change the bulb to a 32v bulb. In fact, I ordered a couple of Perko overhead lights from Sams a few years ago and they sent the fixture with 12v bulbs installed and just threw in a couple of 32v replacement bulbs (because they knew I needed 32v).

 

[Angela]

I've been ponding this situation for a while now. I want to upgrade the OEM 32v reading light fixtures in the staterooms. Are you saying that I can simply put in a 12v fixture and just use a 32v bulb? Is it that simple? Can the wiring inside the light fixture handle that?

 

[SKYCHENEY]

I've been ponding this situation for a while now. I want to upgrade the OEM 32v reading light fixtures in the staterooms. Are you saying that I can simply put in a 12v fixture and just use a 32v bulb? Is it that simple? Can the wiring inside the light fixture handle that?

That's right. Or, you can also install a 120v fixture and put a 32v bulb in it. I have 2 of them in my master stateroom, the lamps on the arm at each side of the bed.

 

[Angela]

Or, you can also install a 120v fixture and put a 32v bulb in it.

Really? Now, that's really good to know! That really opens up my choices quite a bit, and I won't have to pay "boat" prices for the fixtures either!