in good shape, isolde - part 5

This resumes from a previous post in good shape, isolde - part  4. Adapt and evolve is the password of this post of continuous enhancements. Sometimes a solution is so simple that is deceptively obvious when you see one.

Back in 2013, I designed and built a compact power utility panel for Brunnhilde. It was a project of what I like to call making lemonade out of lemon. One of the two cup holders in Brunnhilde's cabin was broken from someone tried to repair it.

Unfortunately the repair attempt made it worst and the plastic spring fingers were shorten that the mechanism binds badly. Upon my inspection of the cup holder I realize there is a circular hole on the Westfalia trim which I can utilize to turn the broken cup holder into a 12V power duplex panel. I had made a similar 12V power utility panel for Isolde.

I made this quad 12V power panel for Isolde about 20 years ago. I chose to use the 4-pin XLR connectors made by Amphenol that I picked up at a surplus store. It is a proprietary system that I created together with a number of adapters and devices which has a compatible plug.

Isolde's quad-outlet power panel that also has a dome light override switch (and a green LED to help one find the switch in pitch darkness); two outlets are supplied by the starting battery and the others by the house battery

When I set out to modify the cup holder into the duplex 12V power panel I searched for the 2 XLR receptacles that I would need. I had none left. As I went online to find them most I could find were low quality knockoffs from China at somewhat reasonable prices. I would eventually find the same Amphenol part at Digikey, at close to $20 apiece! I decided to rob them off Isolde's power panel. To cover up the blank holes left behind I replace the two in Isolde with 2 3-pin XLR that I also had. They are meant to be a short term cosmetic stop gap until I have time to find a solution.

the broken cup holder cum 12V power panel in Brunnhilde

A few months ago I purchase a number of replacement parts for Isolde. I also found a light fixture used as "dome" light in Vanagon and in most VW vehicles in that era. To me it is an excellent light fixture that attract very little attention. It is made by Hella as auto OEM part and cost under $7. I bought one without finding a use for it, although I vaguely thinking I might be able to use it to add a light in Isolde.

In Isolde one area that sorely need lighting improvement is the kitchenette pantry when preparing a meal in the evening. I toyed with a few ideas of a simple and intrusive lighting in a few locations that will illuminate inside the pantry just enough. I identify three options.

1. Glue down a segment of LED strip light on the small ledge at the front of the air conduction duct by the sliding door. The strip light will function as indirect lighting.
2. Install the Hella dome light I bought in the air conditioning duct left of the air vent by the sliding door.
3. Modify Isolde's existing power utility panel by the sliding door to accommodate the Hella dome light.

a 3-meter string of warm white LED strip lighting from China

I cut a 3-LED segment to experiment with

option 1 - LED light strip as indirect lighting

To test out how good the Hella dome light fixture will illuminate my target area I temporarily covered the back with a black glove and rubber bands to prevent stray light.

I installed a warm white 12-LED bulb inside

option 2 - mounting the Hella fixture to the AC duct

option 3 - install the Hella onto the existing power utility panel

The results from my mock up tests were very conclusive. The LED light strip as indirect lighting is the worst in light quality and usefulness, not to mention it would be a tacky installation. Mounting the Hella onto the AC duct is not bad, but it is too high for the indent of illuminate the inside of the pantry. The clear winner is mounting the Hella fixture onto the existing power utility panel.

Option 3 also resolves the two defunct XLR receptacles. It would turn out to be a elegant evolution to the power utility panel that I created 20 years ago, in taking it one step forward with its diminished utility as a result of the recently installed power utility panel on the side of the kitchenette.

the recently added power utility panel diminishes the old one by the sliding door

Well, the $6.90 question is does the Hella fit? I knew it will be very tight if not impossible without making a new one with the same electronics project box.

my idea is to eliminate one column of the XLR to make room for the Hella fixture

I have to worry about interference with the screw posts inside the project box also

After I did the dimensional rough check with a ruler I was quite sure there is just enough space.

shut off power to the panel by removing the fuses

here you can see the two dummy XLR receptacles at the bottom

while locating the Hella fixture to the right side is preferred the existing rocker switch making that not possible

nice! you can see it just barely fit - escaping interference of the screw posts inside

The process took me 4 hours. It took so long because the project box is crammed with wires so all the connections have to be soldered, and most done in-situ. The Hella fixture switch has three positions. I want to take advantage of it and I succeeded despite the crammed fit of the compact project box. While the Vanagon's dome light is powered by the starting battery. I wired the new Hella fixture to be powered by the house battery bank. With a bit of thought I was able to take advantage of the existing rocker switch function for the new Hella light.

Here are the overall functions of the power panel by the sliding door:

12V Power Receptacle
One each powered by the starting battery and the house battery banks
Both can be used to connect to a power charging source - a charger or a generator to recharge the batteries in the field

Driver Side Dome Light
the dome light above the driver seat functions as from factory
when the driver side dome light is set to on always, it is on always
when the driver side dome light is set to center position, it is off always
when the driver side dome light is set to on when any door is open, it functions as from the factory with enhance function - can be switched off by the rocker switch even if any door is open (including the sliding door); when switched off by the rocker switch, the green LED help one find the switch in pitch darkness

New Hella Light Fixture
It also functions exactly like the driver side dome light but serves the horizontal illumination of the entire Kitchenette. It also throws enough light allow one to see under the bench seat when converted into bed as well as the little storage compartment next to it.

I cannot be more pleased with the result. The Hella fixture is excellent. The fresnel lens does an excellent job of diffusion and dispersion of what commonly LED lights problem. While there are 12 LED light sources in the bulb, at the distance to the front surface of the kitchenette there is no hint of uneven illumination. The new fixture serves as an excellent ambiance lighting at night when you are relaxing with a good CD. It is hard to capture the light quality and effect with camera without spending time setting up a tripod on an DSLR. It is one of the best $6.99 I spent.

this is taken with the iPhone 6S Plus without flash or external lighting

a uniform wash of light on the cabinet front

still eating the roasted chicken