Light fixture wired incorrectly?/LED bulb suggestion?

[trflgrl]

This is my galley light: PERKO Inc. - Catalog - Lighting Fixtures - Dual Voltage Surface Mount Light [0318]
At the moment I can't remember if it's oriented with 12v is on the left and 120v on the right; if that's important, I'll report again after visiting the boat. For this exercise, let's assume 12v on left and 120v on right.

Anyhoo:
It has only 2 bulbs in it total, lower socket on the left and upper socket on the right (just because it I've left it the way it was when I bought the boat). After I turn on the "cabin light" switch at the helm, I can turn on this fixture whether using shore power or boat power. Both bulbs light whether I push the Low or High button, and there's no difference in the brightness.

This hasn't been an issue because the brightness level is adequate, but now I'm changing to LED throughout the boat, and First Mate and I have been taking the "make it right if we can" approach each time we do a project.

So my first question/assumption is: is this fixture wired improperly, if it works the exact same way no matter whether shore or boat power? I'm thinking the left side should turn on only under boat power (one bulb on low, two bulbs on high), and the right only on shore power. (And of course this is no surprise....most recently, First Mate discovered incorrect wiring while replacing stereo: both boat leads and both radio leads were twisted into a single cap. Grrrr.)

Second question: when I tried to add a second bulb to the left side, I got a pop and a spark. Bulb itself didn't blow out, but I removed it. Could this be an additional symptom of improper wiring?

Third question with variants: any opinions on what bulbs to use on either side? MarineBeam suggested its Ultrabright 21-LED Bayonet 1141/1142 replacement or the 18-LED Power Tower for the 12v side. I'm thinking the 18-LED will suffice, because I don't need super-bright in that location--just getting low/high differentiation will be grand. Any other preferences? MarineBeam had no recommendation for the 120v side--anyone else have thoughts?

Much appreciation!

 

[BryanOnTheBay]

I clicked through to the wiring instructions for the light (http://perko.com/images/catalog/pdf/Fig 318 Inst.pdf) and the instructions say the low power switch is supposed to be the 12v bulbs and the high power switch is supposed to be the 120v bulbs. Basically, it seems like you should have 2 12v bulbs and 2 120v bulbs, so it does not sound like it is wired properly.

As as to using an LED in the 120 v side, that is not a huge concern unless you really want to replace the 120v incandescents. You are not facing a lack of power if you are on 120v, so the only reason would be heat. The 120v bulb looks to be a 15w T7 based bulb. This is seems to be the standard appliance bulb base, so they should be readily available at Home Depot, etc.

Hope this helps.

Bryan

 

[trflgrl]

Thank you--must have been a really bad day on the Internet for me not to find the instruction doc you linked, so I appreciate it. And your suggestion about leaving the 120v side as is clears the foggy brain: I've been so focused on the mission to swap that I forgot about why we're doing it in the first place!

15w T7 threaded base bulbs definitely aren't installed--the sockets look to be push/twist and currently hold 1141/1157 type bults, so that will take another look.

The fun continues!

 

[trflgrl]

Double post.

 

[trflgrl]

Update: after inspecting this fixture more closely and finding socket damage/cracked fittings, replacement appears to be the best plan, but WOWZAS: 1:1 swap is minimum $100, and that's with traditional bulbs, not LED. I'm optimistic that the available wiring is 12v/120v, though I haven't pulled the fixture yet to verify for fear of causing more damage/losing the current lighting and being forced into a decision faster than I prefer.

Before I do....anybody have suggestions for an alternate LED fixture? Would be nice to have low/high or dimmable features....and I guess if it comes back to the same Perko fixture, I'll suck it up and then get LEDs for the 12v side.

TIA!