Russell Shilling Posted July 6, 2009 Share Posted July 6, 2009 What do Light-o-Ramas do during the summer?They control fountains! Well, maybe they do.Q: Will a LOR control an inductive AC load? What is the limit of their current carrying capacity as the rush current happens when a solenoid is activated?(I have some solenoid operated water valves on order -- I hope that doesn't void my warranty!)Q: The LOR uses pulse-width modulation to control "voltage". How will that work when fed through a halogen light transformer? Link to comment Share on other sites More sharing options...
-klb- Posted July 6, 2009 Share Posted July 6, 2009 Russell Shilling wrote: What do Light-o-Ramas do during the summer?They control fountains! Well, maybe they do.Q: Will a LOR control an inductive AC load? What is the limit of their current carrying capacity as the rush current happens when a solenoid is activated?(I have some solenoid operated water valves on order -- I hope that doesn't void my warranty!)Some non linear (not resistive) loads have been shown to impact the ability of the controller to fade other channels, and even other controllers. However, I am not personally aware of any cases of permanent damage. There is no published data indicating anything above the standard 8A per channel, but in my totally meaningless opinion, I would think you would be safe with an inrush of twice that.Russell Shilling wrote: Q: The LOR uses pulse-width modulation to control "voltage". How will that work when fed through a halogen light transformer?The DC cards use PWM at 400Hz. The current AC cards use phase angle dimming, which intrinsically is 120Hz on 60Hz power, and 100Hz on 50Hz power. How well that works really depends on the transformer. Ones that state that they can be dimmed with a conventional wall switch dimmer should be fine.As for phase angle dimming, the triacs switch off when the current though the load approaches zero, which with resistive loads should be at or extremely near the zero crossing. The controller senses the voltage zero crossings, and calculates how long to delay firing the triac in order to get the intensity desired. Non linear load can mess up the controller by causing the current to reach zero way out of phase with the voltage zero crossing, causing totally the wrong length of on time per cycle. Unfortunately, some times you just have to try it out, and see the results. Link to comment Share on other sites More sharing options...
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