Fixing a 30 yr old aquarium lamp – electronics intro

We have a somewhat neglected aquarium at our home. I’ve got it from my childhood home, making it about 30 years old and almost all parts are original. Well the light went out. and I thought it was the neon tube that finally gave way but upon opening I realized that I have to start to look into replacing old electronics.

I started off removing the the neon tube and found out that the code on it doesn’t match anything in the stores anymore. Yes, it’s an 18 watt lamp, but the measurement is way off. I bought a new tube based on my measurement and it fit. But the lamp didn’t work. I also replaced the starter, but still nothing. So nothing else left than to open the casing.

Replacing old electronics
The 30 yr old fluorescent tube

The extruded aluminium casing is in a good shape, although some of the plastic clips have started to crack. As soon as I opened the casing, I noticed a component that had blown up. I’m not that experienced with electronics, and a capacitor to me has always been a cylinder. So I took a phone call to a good friend and he immediately called it a capacitor. Which makes sense, since those are the components that usually give way.

Replacing old electronics
The light opened up, with some “soot” visible in the casing.

My friend pointed me towards an interesting article about the differences a safety capacitor does in a circuit. With the help of the article I realized that a “fuse” needs replacing as well. Since the lamp doesn’t have a fuse, the most likely blown component was the switch. I used a multimeter to realize, that there is no electricity coming into the system.

Replacing old electronics
The blown up component
Replacing old electronics
Blown up capacitor

The history lesson that I learned from my brother-in-law, was that in the 70’s there was a realization, that a lot of appliances used reactive power, especially the fluorescent lights. So capacitors were added to reduce the reactive power consumption. Since I’m an individual and I have a electricity contract for a household, I’m not charged for reactive power. So it’s possible for me to just remove the capacitor and be happy.

So I did. I ended up fixing this lampi, by removing the capacitor and the switch. Who would’ve known.

While looking a replacement capacitor, I might have gotten a bit carried away. I have earlier ordered a temperature controller for my meat aging fridge, and┬álately I’ve been making investment calculations if I’d increase my production to a commercial scale. Should I do that, I’d need networked temperature controllers. So I added some components based on this article to build my own. So stay tuned.

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