Aqua Signal Series 25 Mast Light

The anchor light on the mast of many Ranger Tugs is the Aqua Signal Series 25 Masthead 12V. Every once in a while, a question is posted about how to remove the lens assembly on this light to access the mounting hardware, the bulb inside or to check wiring integrity.

The Aqua Signal Series 25 has two pieces, the base and the lens. The base fastened in place on the mast with three screws and nuts. The lens assembly attaches to the base using a bayonet mount.

To remove the lens assembly from the base, push it down slightly and turn it counterclockwise slightly and then pull up. It takes very little rotation to release it, less than 1/16 of a turn.

The tabs on the bottom of the lens assembly are indexed to the base— one tab is larger than the other two. When reinstalling the lens assembly, position it so that the larger tab is aligned with the larger slot on the base, push down slightly and turn clockwise.

Here is the Aqua Signal Series 25 with lens assembly separated from the base. The lens assembly is shown upside down to make the tabs visible.



If you wish to replace the incandescent bulb with LED, here are the two choices:

For made fixtures before September 2010, use this bulb:

https://store.marinebeam.com/30-led-44m ... fs-44-30b/

For fixtures after September 2010, use this bulb:

https://store.marinebeam.com/30-led-42m ... fs-42-30c/

If you’re unsure of the age of your fixture, the only way to tell which bulb your fixture requires is to check the bulb currently installed.

Marinebeam LEDs are more costly than what one finds at WalMart, but they don’t emit RF that interferes with VHF radio and AIS operation. The USCG has put out a bulletin on LED RF interference.

I’m posting this for folks who may search the forum for information about the Aqua Signal 25 in the future.

Good topic and information Bill.

Last year while we were looping our goal was to anchor as much as we can. I installed extra batteries and 600W of solar so we could comfortably anchor and be able to use all amenities and maintain decent reserve battery capacity. I have a two bulb anchor light. This is a Perko light fixture that uses Perko Festoon Bulbs 10 watts ea. or .80 amps. X2 for this light. I replaced all of the bulbs in the boat before leaving on the trip to LED with the exception of the anchor light. Probably the most important light to consider changing but I forgot about it!!?? I would check each morning to see how many AH we used over night. Most nights the house bank would be down to 68% to 70%. This always seemed extreme. I have a Victron battery monitor set up, 100% = 400 AH. We were using 120 AH From the time the solar quit producing in the evening until either we left anchorage and engine charge kicked in or Solar kicked in and started charging the house bank.

About two months into our trip I noticed in the early evening that one of the anchor bulbs burned out. I had a couple spares both bow and anchor lights use the same bulbs. I left the light on when I went up to change the bulb. When I grabbed the light fixture lens it was extremely hot (burn my fingers hot so at least 140F) That is a lot of wasted energy and that was just one bulb. This was my reminder that theses bulbs need to be changed to LED. I changed all cabin lights, cockpit lights, pilot house lights to LED to conserve energy while on the hook but not the one that is left on all the time at night. The replacement LED's are brighter than the original and consume 1.1 W or .12 A. The difference of AH use between the two was noticeable. Math would show about 14AH difference. My monitor showed 20 AH difference. The Victron monitor morning reading averaged 75% to 78% for the rest of the trip.

Bills information should be a reminder to all to check your navigation bulbs, clean the connections and if you are still using incandescent bulbs change them over to LED Brighter and use far less 12V stored energy. I believe most newer Fluid motion produced boats have LED. It was an option on my C26 2016.