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Great idea. How in the world do you do that?

My first theatre had the new Strong switchers. I loved the potentiometer for adjusting current, rather than messing with the taps. I also loved being able to change out the whole thing, rather that having to change diodes or something else if the rectifier goes bad. And I love the trouble lights!!! However, within a year, we had three go bad. I have heard similar reports from other theatres. (Someone told me he had 3 go bad in one week!) So I guess there's a little give-and-take either way you go.

As far as trying to trouble-shoot one, you're not supposed to! They are not user serviceable. I suppose that's why they're so easy to change out. Just pop in your spare and send the old one back to Strong.

Shut down the fans in one and you'll change your mind! They actually get quite hot with out a fan and will shut down. In the switchers its the fan that keeps em cool. Older Strong switchers were notorious for overheating when you used them in a booth that was hot say in the summer. I've been to booths that hvae the tops removed and have a 3 foot window fan blowing on them!

In any rectifier that has diodes, the diodes are only rated for so mnay thermal cycles before they will mechanicaly fail. I have seen alot of this in older Christie rectifiers and some Irems but mainly those rectifiers that have no cooling fan. Also diodes that use that green epoxy type seal are prone to literally fall apart after a number of years. Using diodes that are glass sealed will allow much longer life and more thermal cycles. Even if a rectifier is fan cooled the diodes still go through this thermal cycling at the silicon chip. There is some thermal resistance in the diode itself so the actual silicon chip itself runs a bit hotter than the diode casing, and there is another thermal joint adding resistance between the case and heatsink. Lotys of heatsinking and or fans are the only way to reduce this failure but you will never see a rectifier that never ever fails at some time in its useful life.
Mark @ GTS

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The newer Strong consoles we have been receiving in the last couple of years or so, however, have been equipped with intake fans on the non-operating side of the door. These fans seem to help greatly on cutting back on the number of failures.

In problematic booths, (those that have had 2 or more failures)(usually 7K), I have added fans to these older consoles and, touch wood (knocking on head), have not had a failure in over two years on these units.

I would like to know, for those of you who have experienced failures with switching rectifiers, did they fail at the start of a show or during a performance?

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Still, I have had some luck (and learned a lot) with repairing them (not without some help on finding information from some of the people here on Film-Tech). I agree with an earlier statement Paul made, in another post, about it being easier to send them back to the factory for repair.

However, with the hassles of getting them through customs (CAN. - U.S), plus the time incurred being without a spare rectifier, and no, we don't yet have 7K reactance types on hand, not to mention the logistics of getting a heavier than sin reactance type up to the booth on a Saturday afternoon to save a show for the weekend, I have no choice.

If you blow a power supply or a lamp, just simply grab your spare power supply and lamp, drag it over to the station, throw the lamphouse on the pedistal, plug it in, light-'er up, and you are back on the screen!

Consoles, well, you are basically screwed if it was a switcher or any power supply and/or lamp failure.

Funny thing is, when Regal bought our theater, they acted like I committed an unforgivable sin by having a spare lamphouse and power supply sitting on a dolly "ready to go". They threw it away! What idiots!

Word also got to me that shortly after they bought our theater, (and I was no longer part of their HS operation,) two day's worth of shows were lost because of an exciter lamp failure. Yes - a stupid exciter lamp burned out! I was told nobody was allowed to change it.