I provided a bit of misinformation in my original question but it doesn't really change my question. The new voltage stabilizer that I just bought is made by Unicolor, not Aristo, as I wrote.
I have never measured my voltage fluctuation and, as a matter of fact, it never seemed to be an issue even before I got the Zone VI stabilizer for my other enlarger. However, when I am running water in my darkroom, which is in my 90 year-old house with it's old wiring and fuses, the water runs into my sump and is then pumped out by my sump pump. I believe that might cause voltage fluctuations. Also, depending on the time of year, my furnace blower motor and/or my A/C compressor motor may be going on and off during printing sessions. In any case, I added the Zone VI stabilizer years ago because I got a great deal on it and it can't hurt anything. I have have been watching for a similar stabilizer for my other enlarger just so the setup is the same for both enlargers and the one I mentioned came up on eBay a couple weeks ago. It is not identical to the Zone VI stabilizer which has a dry-down control, but all I really want is stabilization. (I don't use the dry-down feature.) But when I went to hook it up today, I saw that it only has a 100W load limit and I don't think that is enough even though the seller said it could handle an Aristo or Zone VI 4x5" cold light.
As for the heaters, I don't run them through my timers (or stabilizer), of course. They are plugged in separately during my entire printing sessions as they should be. Only the current going to the lamps goes through the timers. I also use contactors with both enlargers to isolate my digital timers' circuits from the current draw of the lamps but that is another unrelated issue. I just thought I would mention it. However, my contactors have 1,000W continuous load limits (1,200 intermittent). They are made by Aristo and recommended by Aristo for my heads when used with some digital timers but they may be suitable for use with larger heads too. But I don't think the 100W limit of my new stabilizer is enough to handle a 4x5" cold light. In fact, I suspect that if I tried to use it, I would burn it up.
BTW, I know very little about electronics other than the very basics - house wiring, etc.
In case anyone suggests it, I know that it would be better to have a compensating timer or compensating metronome that actually measures the light output and compensates for light output fluctuations and I do keep an eye out for them but they don't come on the market that often and, when they do, they are too expensive for me.
Anyway, what I would like to find out is what the the minimum load limit should be for a stabilizer that I would use on my other enlarger with it's Aristo 4x5 cold light.
Last edited by ZoneIII; 03-06-2010 at 08:04 PM. Click to view previous post history.