SA303 12V DC 3 Wire 3-point

SA303 12V DC 3 Wire 3-point or Floating point: The actuator has both clockwise (CW) and counter-clockwise (CCW) control inputs. When the voltage is given to one terminal it drives the actuator to its open, the other to its close position. If power is not given to either of the inputs, the actuator simply stays in its last position.

Details of the connections are as follows

• In the above circuit, the Black wire is connected to the Negative/Neutral of 12V AC or DC and 12V AC Phase when connected to Green wire the Valve will Open.
• When the Phase/Positive 12V AC/DC is connected to Red Wire the valve will Close. There will be a movement in the actuator in the corresponding direction as long as the input is given, which is called as floating point.
• Suppose assume, the operating time of the valve is 10 seconds for 90°. When the positive 12V DC is trigger and hold for 5 seconds the valve moves to 45° Open and when the voltage is removed it stays in that position. Also again when the +12V is triggered again for more than 5 seconds also it open fully and the internal motor stops after hitting the stopper limit switch.

Use of internal Limit Switch:

Inspite of the actuator is 3 point floating control, after the full open or close limits are trigerred the internal motor stops. So regardless of the duration of the power given to CW or CCW terminals the motor will stop rotating.

Floating point control is used as a partial alternative to proportional control. It can be used to control the angular position of the valve with proper feedback mechanisms.