Some applications may need more than one control input. Trap doors (access hatches) are a great example, since they need to be opened from the inside and the outside for safety.
To have multiple-controls, your system will require relays. A relay is an electrically-automated switch. To learn more about relays, read this tutorial.
In the above diagram, there is a Rocker Switch and a 2-Channel RF Remote System connected to the Coil Pin of each Relay. The control inputs are separated from each other by diodes. The other Coil Pin is connected to ground to complete the DC circuit. The core of a multi-input actuator system is the pair of SPDT relays, which keep the 12vDC power circuit away from the lower-voltage (or lower-current) control circuits of the other components.
A diode is like a one-way valve for electricity. They are required when using our RF remote systems. If the diodes are not included, using the rocker switch will cause electricity to back-flow into the RF Remote unit, which will short and burn out the PCB components and make the remote receiver useless.
When any control component is activated, it will send electricity through one of the relay's coils, activating the relay and switching the connection from COM-NC to COM-NO. When wired correctly, this switch takes the actuator's motor lead from Ground to the +12v connection, completing the motor circuit through the relays, which activates the motor in the desired direction. No power actually travels through the control components - all motor power is moving through the much more robust relays.
Using relays can allow you to include any number of control components. The diagram above shows how to connect several at the same time - as long as the diodes are correctly installed, any one of the control inputs would have full control of the actuator system, though only one control input can be used at a time. [If two controls were activated for opposite motion, the actuator wouldn't move; the actuator is not harmed in this instance]
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2x SPDT Relays
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1x Double Wiring Harness [for easy installation and connection]
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Linear Actuator (any) and Actuator Mounting Brackets
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1N4007 Diodes [not stocked]
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Control Inputs
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12vDC Power Supply for Linear Actuator
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High Current (motor) Wires:
- NC - Yellow: 87 (connect to positive from power)
- NO - Red: 87a (connect to negative from power)
- COM - Blue: 30 (connect to actuator leads)
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Control Coil Wires:
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COIL1 - Black: 86 (connect to negative from power)
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COIL2 - White: 85 (connect to control outputs)
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But their is an easier way
If you want a simpler solution to operating an actuator with 2 or more conrol options, then you can use the FCB-2 This is a plug and play control board that allows you to control Actuator by remote control and a manual switch with very little wiring.