摘要 |
A control system and circuit for use with one or more inductance-type actuators, such as solenoid controlled water sprinkler valves, having a relatively low impedance at low frequencies, which serves to operate the actuators, for example, when ground moisture falls below a preset level. A sensor having a relatively high impedance at low frequencies, and which for example may be moisture variable, is provided for each actuator. The control circuit is connected to the actuator over appropriate electric leads, and the same leads are used to connect the sensor back to the control circuit thereby obviating the need for extra wires and difficult retrofits.
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