We just got a new Aristo cold light head (model 57-C-V54-110V) and we're trying to figure out how to make it work right and wondering if it might be defective.
The unit is a single metal box with a switch on the side, and 2 power cords coming out - one thick 3-prong, and one thin 2-prong. The unit was shipped new but didn't come with instructions (grr!), but I found some instructions on the aristo web site. They aren't terribly clear, but I think I can puzzle out the following:
1. The thick 3-prong cord ("thermo cord") and switch ("thermo switch") are for the heater/thermostat; the thick cord should always be plugged in and the switch should be left on all day while you're using the unit.
2. The thin 2-prong cord plugs into your timer and is used to turn the light on and off.
But our unit isn't behaving as expected from the above, instead what we are seeing is:
1. If we plug in the 3-prong thermo cord and leave the 2-prong cord unplugged, we can turn the light on and off using the thermo switch. That doesn't seem to make sense since the lamp shouldn't go on unless it is getting power from the timer, right? So if the unit was working right, the lamp should never go on with the timer cord unplugged, right?
2. If we then also plug the 2-prong timer cord into the timer, it doesn't make any difference whether the timer says the lamp should be on or off, the lamp still only goes on and off when the switch is used. (We know the timer is working because we use it for other stuff).
So... If anyone is using this device or similar, please let us know if ours seems to be defective, or if we're just confused (and if so, please shed some light on the situation!).
-- Alex Benenson
P.S. I find it hard to believe that a $350 piece of darkroom equipment doesn't include instructions!