DO-E Modules Outputs

The outputs are optically coupled. The optical coupler (also called an opto-isolator or opto-isolator) provides the transference of the input state while providing complete electrical isolation. Electrical isolation is of paramount importance in applications such as greenhouse control.

The output does not supply any current. In this regard, it may be considered as a normally open, dry contact, switch.

The following diagram gives a simplified schematic.

As seen from the above circuit, the output transistor switches an external signal. The plug is polarized. That is, the (+) and (-) terminals of the plug must be connected so that the DC current flows from the (+) terminal to the (-) terminal when the output is switched on.

The output transistor is rated at 250 mA (milli-Amperes), 36 Volts, and 300 mW (milli-Watts). This rating is for a continuous signal.

Often, the output is used to trigger high-power loads, such as fans, pumps, or heaters. In this case, the output should be used to switch a power relay. The following schematic shows the use of a secondary high-power relay. Notice that you must drive the relay using an external power source. The circuit below uses a DC relay, and hence the signal switched by the module output is polarized. If you use an AC relay, you must provide an AC power source. In either case, the module output can switch the current.

© Rigel Corporation iNetGrow 2003-2006. All rights reserved.