AC and DC engine room lights?

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wkearney99

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Feb 17, 2018
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USA
Vessel Name
Solstice
Vessel Make
Grand Banks 47 Eastbay FB
My Eastbay has both AC (fluorescent) and DC lighting in the engine room. My question is if I'm going to replace them with LEDs do I need to continue to have AC units?

I'm thinking that in 2005 they used the AC lights to provide a LOT more lighting than DC units could provide at the time. With modern LEDs that's less of a problem. There's a lot more options now for LEDs that use DC, in all kinds of form-factors. That and all of the LEDS now use considerable less wattage for the same amount of light.

My question is should I even bother continuing to have the existing fluorescent fixtures powered by AC? A simple solution would be to get some LED replacements designed to fit like the fluorescent tubes. Most of those require bypassing the AC ballast, which is not difficult. I've done that in some basement light fixtures and that works fine. But unlike the house, the boat has 12vdc everywhere, so should I even bother keeping the AC lighting active? Should I just bring 12vdc to their fixture and convert them to DC?

Or just remove the AC fixtures entirely and replace them with DC LED units?

I get there's some value to redundancy, but if I've lost 12vdc power and need engine room lighting what's the likelihood I'm going to be able to start the generator to get AC power for them? Seems like switching to all DC and decommissioning the AC engine room lighting is a better plan.
 
I think that going all DC LED lighting makes sense. But you need to pull all of the old AC wiring back to its origin. I wouldn't just terminate with a wire nut or something.

David
 
If the AC fluorescent fixtures are working, just leave them there. Power consumption usually a non-issue if you from some source have AC, and it is not that much power. And yes, sh!tcan the DC incandescents and swap to LED.
 
Our engine room also had 115 vac fluorescents and 12vdc incandescent. I replaced the 12v with leds and replaced the whole fixture units with 115 vac led fluorescent replacements. Get lots of light with the 115 vac leds. My thinking was, most major engine work would be done at dock, or on hard and I’d be plugged in for the ac leds. If at anchor, etc, 12 vdc would work, but could also crank up the generator if need more light. I find that the older I get, the more light I need to see by.
Gary
 
Some of the AC fluorescents are flickering. As in, it takes a few taps on them sometimes to get them to stabilize. Not a big surprise out of 12 year old lights. So it's either fix or replace them and I'm leaning toward replace.

I'd definitely remove the AC wiring if I remove the fixtures.

Right now it's up on the hard getting the bottom repainted, and doesn't have shore power plugged into it. So I can't use AC lighting. Well, I probably could via the inverter but I haven't yet figured out how to turn that system on yet (not the obvious 'turn the handle' on the panel). But that's a whole other thread...

The other advantage to changing out to DC fixtures would be gaining some headroom. The AC fixtures are big, probably sticking down about 5" from the ceiling of the engine room. It's a 5'9" ceiling but I'm 6'3". So a couple of low profile surface mount fixtures would be a welcome change.

I'd be willing to consider a track of LED strip lighting if there's something out there suitable for engine room installation. I have no desire to half-ass this installation. I'll spend to get the correct sort of setup.
 
I think that going all DC LED lighting makes sense. But you need to pull all of the old AC wiring back to its origin. I wouldn't just terminate with a wire nut or something.

David


Yes.... other option would be to buy a 2 lamp 4' Vapor Proof 120 VAC fixture in place of what's there. ( they are about 100.00 +/- ea. ) As was said somewhere, most work is done at the dock and even if it was not, the power via Inverter to power these AC LED fixtures would be negligible.

Re: old AC wiring by going to DC, assuming that the lighting circuit does not go anywhere else, I would leave in place and just remove from AC source and re route to DC source, the existing 120 Volt switches will most likely be o/k on DC .....

fb
 
We had both 12vdc and 120 v florescent lights in our engine room, too. Went through the same thought process as you. Ended up yanking out the 120 v fixtures, additional headroom being one of several reasons, and replaced them with six LED light strips. SUPER bright! Lights it up like an operating room. Never regretted it. Doubt you will, either.
 
We have this style of fluro.
Unfortunately we paid more than $36 for them

WPF118.jpg


https://www.mjselectricalsupplies.c.../1-x-18w-weatherproof-fluorescent-batten.html

Adding in some cheap led work lights as well now, getting a bit sick of flickering fluoros., have had to replace starters and bulbs on some after less than 12 mths and probably 12 hours use
 
We had both 12vdc and 120 v florescent lights in our engine room, too. Went through the same thought process as you. Ended up yanking out the 120 v fixtures, additional headroom being one of several reasons, and replaced them with six LED light strips. SUPER bright! Lights it up like an operating room. Never regretted it. Doubt you will, either.

Link to the led strips please.
 
When I bought my boat it was fitted with a mix of dc and ac light. I hated to be able to turn some on when at the dock some when at the anchor. I replaced everything with only dc leds last year and I cannot be happier!

L
 
Yes.... other option would be to buy a 2 lamp 4' Vapor Proof 120 VAC fixture in place of what's there. ( they are about 100.00 +/- ea. ) As was said somewhere, most work is done at the dock and even if it was not, the power via Inverter to power these AC LED fixtures would be negligible.

Re: old AC wiring by going to DC, assuming that the lighting circuit does not go anywhere else, I would leave in place and just remove from AC source and re route to DC source, the existing 120 Volt switches will most likely be o/k on DC .....

fb

The AC wiring is going to be much smaller, better make darn sure it can handle the total possible load on the circuit. Personally I'd just leave the AC in there. I liked having both in my ERs and saw nothing to gain by the time and investment in conversion.
 
My boat had both AC and DC lights. First I changed out all the DC light fixtures to a Very bright LED fixture. This gave me more light than the previous fixtures combined. Next I converted the AC fixtures to AC outlets, this gives me the option of adding a drop light or other power tools. In my case the ACwire was already 12 gauge but I had to run a ground wire to make things safe.
 
My boat had both AC and DC lights. First I changed out all the DC light fixtures to a Very bright LED fixture. This gave me more light than the previous fixtures combined. Next I converted the AC fixtures to AC outlets, this gives me the option of adding a drop light or other power tools. In my case the ACwire was already 12 gauge but I had to run a ground wire to make things safe.

That is what I would do if I had 120 volt lighting. I had 2 dim incandescent 12 volt lights in the engine room. Replaced both with LED and added another. Now it is very bright. I had 120 volt outlets in the engine room on a previous boat and used them pretty often.
 
I replaced the fluorescents in three engine room lights with LED tubes from Marine Beam. The ballasts must be removed, an easy fix. When removing the ballast from the one light which was not working at all, under the cover I found one to have had significantly melted, frightening to me. Now the ER is as bright as it can possibly be in all corners. Keep the AC fixtures, remove the ballasts, and install LED tubes. You will be happy.
 
I replaced the fluorescents in three engine room lights with LED tubes from Marine Beam. The ballasts must be removed, an easy fix. When removing the ballast from the one light which was not working at all, under the cover I found one to have had significantly melted, frightening to me. Now the ER is as bright as it can possibly be in all corners. Keep the AC fixtures, remove the ballasts, and install LED tubes. You will be happy.
Nothing quite as unnerving as coming across melted/smoked parts out of sight inside of electrical components.

That's what I had to do with a residential light in a utility closet. I left the ballast in there and followed the directions to direct-wire the circuit to the tube sockets. Works great. I went an additional step and used some neon yellow labeling tape to read "Ballast Disconnected" should someone come along later and make the mistake of using a cheap fluorescent tube for replacement.

Replacing just the tubes would likely be the simplest, but would still leave me with a situation that requires AC power to get decent lighting.

I'll take a hard look at how the DC wiring is laid out and calculate the total load of switching to all LED. Don't want to start down the road of changing to DC only to get into a situation that exceeds the existing wiring/breaker capacity.
 
Bill: Here’s a thread on installing led lights in the engine room. Post 5 picks up where Nautibeaver, a 68’ Nordlund, installed 1 meter long, low proflie lights for pretty cheap. We did the same after seeing his results and couldn’t be happier.

http://www.trawlerforum.com/forums/s4/er-lights-14859.html

That's a nice result. Trouble is with that much fresh light there will need to be some serious cleaning done first before I'd take any pictures!
 
Nothing quite as unnerving as coming across melted/smoked parts out of sight inside of electrical components.

That's what I had to do with a residential light in a utility closet. I left the ballast in there and followed the directions to direct-wire the circuit to the tube sockets. Works great. I went an additional step and used some neon yellow labeling tape to read "Ballast Disconnected" should someone come along later and make the mistake of using a cheap fluorescent tube for replacement.

Replacing just the tubes would likely be the simplest, but would still leave me with a situation that requires AC power to get decent lighting.

I'll take a hard look at how the DC wiring is laid out and calculate the total load of switching to all LED. Don't want to start down the road of changing to DC only to get into a situation that exceeds the existing wiring/breaker capacity.
Great point about labelling the fixtures. As for the AC current draw, a 48" tube from Marine Beam draws 20 watts. I do not know what a 12 volt LED bulb that delivers similar levels of brightness draws but my guess is that the difference would not be significant.
 
I think that going all DC LED lighting makes sense. But you need to pull all of the old AC wiring back to its origin. I wouldn't just terminate with a wire nut or something.

David
X2. I'm replacing ALL AC lighting with LED. Truly makes a difference.
 
I love the old fluorescents on shipwrecks. You can use the 4 foot tubes as light sabers and fight your scuba buddy.
But, as far as USING fluorescents onboard, its so 50's. These things emit RF energy, contain mercury, and just have no real place in the modern world. LED's have eliminated their dominance in energy efficiency, and there are even drop in LED tube replacements.

i don't see any need to run AC around either, since LEDs will work on low voltage DC just fine.

edit: just save one incandescent for when you take a lightning hit and every semiconductor fails.
 
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Bill: Here’s a thread on installing led lights in the engine room. Post 5 picks up where Nautibeaver, a 68’ Nordlund, installed 1 meter long, low proflie lights for pretty cheap. We did the same after seeing his results and couldn’t be happier.

http://www.trawlerforum.com/forums/s4/er-lights-14859.html



I had problems with the DC lights in my aft lazarrette when that thread was going on. I ended up ordering the cheap LED strip lights and fixtures for them. Then I found out that the light issue I had was stupid operator error. I am still thinking about mounting the strip lights on the sides of my ER to give more light on the side of the engine. Sometimes I need to use a flashlight to check the level of clean oil.

Suck to get old.
 
We had the same set up you had when we bought the boat. Had a friend who had some extra AC LEDs he bought at Home Depot, so those replaced the old fluorescent fixtures. Then replaced the DC lights with LEDs from Doctor LED. They are very bright and have red light as well.
 
I've just replaced the DC engine room lights. There's 5 of them. I used a red/white switchable 'dome light' replacement board from Marine Beam.

Replacement was pretty straightforward, just remove the four screws holding the cover in place and swap it out. The replacement uses the same sort of socket, with a short bit of wire connected to the board. Plug in the socket first, peel the sticky tape off the back of the board's foam, tuck the wires up above the board and then wedge the board into the housing.

The hardest part was squirming around to the ones outboard of the engines. I picked up a foam folding work pad a while back and it's offered perfect cushioning to get to everything.

I used a laser thermometer to check the temps before and after. I did the first one with the lights having been off (for better than a month). Temp on the fixture was 85F. After having the replacement installed for about an hour the temp read 85.4F on the board itself. That's hardly any heat at all.

I left the rest of the lights illuminated to get them up to temp. Having run for about an hour, the temp on them read 149F on the housing!

The one thing I didn't take was a picture with the room lit the old way vs the new. I'll try to get a shot of the new lights.
 

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Now I'm debating the fluorescent fixtures. I finally managed to find a source from Aqua Signal for a direct, drop-in replacement assembly. For which they want ~$80 plus shipping from Germany. Oh, and there's only TWO in stock at the factory and it'd be 7 weeks lead time to have more made. Apparently these are more commonly used over there using 240V so getting 110V is uncommon.

I never like getting into custom-built gear for what may be replaceable items. If/when you need another it ends up with even longer delivery cycles...

So I'm going to entertain the idea of using LED replacement tubes and re-wiring to skip the ballast. I've done that in other fixtures so it's not a big deal. Changing out the fixtures entirely would likely introduce other wiring labor and I'd rather avoid that. If just because I'm not looking to make work for myself. But also because when you start moving wiring around you often invite unexpected complications...
 
I should add these red/white switchable units require no wiring changes. You toggle between red and white using your existing on/off switch. They default to red when they've been off. If you want white you just toggle the power off/on and they come up white. You need to leave them off for ~3 seconds and then they'll revert to red.

Coming on red helps avoid losing night vision. I went with these to allow for any unexpected night-time forays into the engine room.
 
I love the old fluorescents on shipwrecks. You can use the 4 foot tubes as light sabers and fight your scuba buddy.
But, as far as USING fluorescents onboard, its so 50's. These things emit RF energy, contain mercury, and just have no real place in the modern world. LED's have eliminated their dominance in energy efficiency, and there are even drop in LED tube replacements.

i don't see any need to run AC around either, since LEDs will work on low voltage DC just fine.

edit: just save one incandescent for when you take a lightning hit and every semiconductor fails.

Heh, agreed on getting rid of the fluorescents. Don't know that I'd play the lightsaber game, what with the mercury and all, but yes it'd be a laugh.

Fair point about lighting and chips. It'd be interesting to hear from anyone that had been hit by lightning if it also fried their LED lighting. I'm guessing it'd be just as likely to fry regular bulbs too if they'd been on during the strike.
 
I have caged lights with clear lens glass that screws into the bases.
They were setup as DC incandescent and they were awful, dim, expensive bulbs using lots of power. they also seemed to burn out soon.

I changed the wire to AC with ground. Connected to AC power. Screwed in 120vac LED 60 watt bulbs, and huge improvement in light output, nice and bright. Existing white handle Carling switch on the panel rated for DC or AC, so it worked fine.

I have 2 inverters and a gen, so as long as I have DC power, I will have AC power.
Either inverter can with simple push of a switch be turned on to run the lights.
All outlets (which includes these engine room lights), I wired up with a DPDT on-off-on 20 amp switch.

I can select the second inverter to power all outlets and lights or leave switch to the default of a user selected shore-gen-first inverter as the power source.

Second inverter is maybe 400 watts was a Minuteman PC UPS that I modified, first inverter 3000 watts. I use the second inverter to run my NAV PC. It can also run all my LED AC lights and my LED TV and charge up the phone at the same time. I put a couple wall mounted AC reading lights on swing arms in the main salon, with the 60 watt LED AC bulbs, gives lots of nice warm light.
 
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Am curious if anyone has converted the entire boat to 120/230VAC instead of 12/24VDC lighting fixtures. Domestic LED bulbs are available anywhere in the world but DC bulbs/fixtures are tougher to replace, plus our inverters are rather reliable these days.
 
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