Having recently discovered the interesting failure mode of metallised film capacitors, where the metallisation layer can gradually erode electrically over time, I thought it would be interesting to test the capacitors in a typical Mountain Breeze ioniser to see if their capacitance value had changed.
The good news is that they all tested fine at 10nF. So the traditional Mountain Breeze ionisers will just keep going.
While I had the ioniser open I also replaced the notorious blue neon indicator with a new orange neon one with two 220K resistors in series for an ultra long life. I also resoldered the needles so that they were protruding about 6mm (0.25") in front of the unit. That allows better airflow around them and makes them much easier to clean.
The good news is that they all tested fine at 10nF. So the traditional Mountain Breeze ionisers will just keep going.
While I had the ioniser open I also replaced the notorious blue neon indicator with a new orange neon one with two 220K resistors in series for an ultra long life. I also resoldered the needles so that they were protruding about 6mm (0.25") in front of the unit. That allows better airflow around them and makes them much easier to clean.
Found this exact one on ebay for 1 euro. Opened it up which was kinda hard to do. Didn't look like it ran a lot since the neon still looked fine and stuff. But i wonder how to make sure it works right since i barely hear any hissing.
You use this in your bedroom? Do you find that it produces a noticeable amount of ozone?
I once tried a somewhat similar-looking needle-type ionizer that was mains isolated and instead had an opposite voltage plate quite near the needles, and it produced and absolutely nauseating amount of ozone. Instead, I ended up getting one of the tall, parallel-plate type units that are very popular here in the US (they may be popular in the UK as well, I don't know).
I don't like that you touched the needles 😛
hi clive.great videos.got a quick question for you.the screwdriver you use to take things apart how much is it? where is it from? many thanks
Perhaps the needles were recessed to minimise the shock hazard ?
Amazing how no matter how many times they update the casing, these are almost always identical inside
Very timely video as I want to check some capacitors in my 200 in one electronics projects lab which is a wounderfull toy, When you test a cap what do you set your meter to?
According to an article on designing reliable PSUs I have in front of me, the voltage rating of metallised (polyester) film capacitor drops dramatically with frequency – one 'popular range' apparently has its 400Vdc 250Vac rating at 50Hz drop to just 1V at 100kHz. This means that they are very susceptible to high dV/dT situations as found in switching semiconductor snubbers and generated by arcs. It goes on to recommend polypropylene, foil film or ceramic instead.
I always used to sit mine on a sheet of A4 paper to collect the dust. Much easier to replace when dirty.
The cheap green and blue neon bulbs uses plain nitrogen that causes the electrodes to sputter onto outer glass shell quite fast no matter how low the current. The clear glass neon's are much more robust, I have one glow in the extension cord switch for years 24/7 and it's light is still clearly visible.
How much current does the entire unit draw when on?