Newfangled fluorescent light ballasts: wire exactly as indicated

Just wanted to pass along something I learned the other day (amazing! actually have enough functioning brain cells for new information!).
A client had an under-counter fluorescent fixture go bad. Weird fixture: uses two T-5 lamps of different sizes (12" & 6"). I looked at it and decided to just replace the ballast, assuming it would be cheaper. To make a long story short, it was a pain in the ass just getting the ballast: took many, many phone calls to the electric supply place, which is actually a pretty good supply house, to locate the correct replacement, order it (including having to fax a credit-card authorization form that they emailed me!) and pick it up.
Anyhow, I finally got the ballast, which was just barely small enough to fit into the fixture. Got it all hooked up the way I *thought* it should go, following the little wiring diagram on the label: that is, connecting the existing wires from the fixture to one of the terminals on the ballast. Connected it to power; no go. I disconnected the wires and connected them to my voltmeter, then applied power: no voltage on the output side at all. That's strange.
Called the electric supply house back, who then gave me the number of the manufacturer, Advance Electric. I called their toll-free customer service number and quickly got through to a technician. After telling him what ballast I had and what the problem I was having. I told him I had only connected to one each of the connectors for each color; there were two reds, two blues and two yellows. I've connected ballasts this way before and they worked (like the ballast I was replacing, which tied the two pins at each end of the socket together).
After looking something up for a minute, he came back and said, well, that unit has lamp failure detection, which is why it doesn't work for you. Apparently, that little ballast is pretty smart: it's got a circuit that detects an imbalance in lamp current across the two pin pairs, which tells it that the lamp is about to fail, in which case it shuts down completely rather than going dim, flickering, etc. (If the bulb goes out, you know it's time to replace it.) The ballast only works correctly when all connections are used, exactly as indicated on the label, with one connection going to each pin of the lamp.
I hooked it up as indicated, and it worked. So I just wanted to pass on this bit of information. I had no never heard of "lamp failure detection". (Plus I have to give this company credit for having pretty damn good tech support.)
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