Hog Slat - Overdrive Triac Dimmer Technical Documentation

www.aglights.com If you no longer wish to receive emails and product updates from Overdrive, please contact us at 800-657-0509 and we will remove your name from our system promptly. LED – Poultry Dimming Today. TRIAC dimming was introduced in 1960 and primarily used with incandescent and fluorescent lighting circuits. It generates a tangential output voltage waveform where the change in voltage is proportional to the current. Incandescent lighting is a simple resistive load with the relationship between current, voltage, and brightness being linear and direct. Until several years ago virtually all dimmers used for poultry dimming operations were designed with triac or triac type circuitry. LED lights are different from incandescent lamps. LED lights rely on drive circuits to provide constant current to ensure proper power and voltage. LED light interactions with a TRIAC are unpredictable. When a TRIAC dimmer is used to control LED lights, the following problems may arise: 1. the dimmer cannot turn off the current completely. In this case the lights cannot be turned completely off or the zero turn off point can vary. 2. Compatibility is questionable resulting in lights strobing, flickering at low levels or lights on the same circuit dimming differently. 3. Difficulty in dimming the lights to low light levels. 4. Some levels of increased lumen depreciation have been observed. Note: The potential problems stated above seem to occur under no linear timeframe. Demands of low dimming levels seem to exacerbate these problem areas. The Overdrive dimmers – ODMR0205 (5 amp/channel) and the ODMR0210 (10 amp/channel) utilize MOSFET circuitry not TRIAC circuitry suitable for capacitive loads, like dimmable LED lights. The MOSFET circuitry allows for smooth dimming curves and flicker free control and operations. The Overdrive MOSFET circuitry is specifically designed for poultry lighting circuits of 22 amps or less. Overdrive strongly suggests that if your present LED’s (especially Overdrive units) are being controlled via a dimmer that is more than 5 years old……there is a good possibility that it is a triac type model. It may be a wise choice to update to the MOSFET designed dimmer. This may also be true if your controller ties directly to the LED’s or through an internal dimmer card. The research engineers at Overdrive are continuing to examine Overdrive LED’s returned by our distributors. We have compiled significant data that shows that 98% of Overdrive LED returns were used with older triac circuits. The Overdrive design engineers found MOSFET circuit design to be best for our Overdrive LED’s. This brief report addresses only the Overdrive dimmable A19 models. Overdrive Lighting 800-657-0509 www.aglights.com