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stevemayman
04-05-05, 03:19 PM
Greetings,

I am installing an array of low voltage lights and have run amok. I understand that resistance in the wires will cause voltage drop as the distance of a fixture from the transformer increases. My understanding stops there.

I was using 16 20-watt bulbs with a 500-watt transformer. The bulbs farthest from the transformer were noticeably dimmer than the closest bulbs. This made sense because the resistance in additional length of wire reduces the voltage to the distant bulbs. Thicker wire would help but is not an option. My solution was to live with it.

The 20-watt bulbs were too dim overall though, so I decided to switch to 50-watt. I swapped my 500-watt transformer for a 1000-watt figuring that it should handle the 800 watts of load. Sadly, the 50-watt bulbs were barely brighter than 20-watt bulbs in the new configuration, even side-by-side.

At any given voltage, shouldn’t the 50 watt bulbs be 2.5 times “brighter” than the 20 watt? Also, what would happen (theoretically) if you overloaded a transformer? Say you put a 100-watt bulb on a 60-watt transformer. My guess is that it would not put out the same light as if on a 150-watt transformer. How would this be explained?

Finally, are there any suggestions or any way to model my situation to predict how to keep all the bulbs bright before making another mistake?

Thanks!

Steve

John Nelson
04-05-05, 03:29 PM
Yes, the 50-watt bulbs should have been considerably brighter than the 20-watt bulbs, unless the bulbs are somehow wired in series rather than in parallel.

An overloaded transformer would probable overheat and burn out.

Can you tell us the gauge of the wire and the distance of the run?