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What is the difference (except price) from analogue actuators and 1-10V control units for dimming lights. I can see that they also work with 4-20mA but when would you need that? |
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It's a big difference between them even if the name is similar. An 1-10V Control Unit for lighting is a passive device. It works like a potentiometer adding resistance to the circuit. The voltage is provided by the ECG:s and attenuates by the load created by the resistance. An Analogue Actuator provide it´s own voltage and is an active component in the circuit. It can provide voltage or create a flow of current depending on what´s needed on the other side. 4-20mA is widely used for analogue communications because it´s not affected by voltage drop and thus very reliable. That is because some old law telling that the current in a given circuit is constant but the voltage may vary. Active 1-10V or currents like 0-20mA or 4-20mA are often used to control valves or dampers. /Max |
