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SmartLink – AC

SmartLink AC wireless relay


The Smartlink Wireless Relay is composed of two units that come pre-paired and ready to plug and play. The system comes as a pair of devices, the transmitter and receiver units.

This is the AC powered receiver that will be wired into the control box.

This is the battery powered transmitter that will typically be mounted near the tank/reservoir.

Smartlink Setup

Below is a typical setup for tank level control using the Smartlink.

Step by Step installation guide

Install Receiver

The receiver can be configured in the following mode:

  1. Dry Contact Mode:

The relays power source is isolated from the receivers input power. This would be used if the relay is powering a 230v AC device. REMOVE the LINK for this mode.


  1. Live Contact Mode

The Input power is bridged to the output of the relay via the LINK. This will be used when your load on the relay needs 230v AC. Ensure that your power supply can supply enough current for the receiver and the load.

NB: Warning, Remove LINK Bridge when applying external power to the relay, damage to the unit will occur if you put high voltage into the receiver with LINK bridge installed.

Dry Contact Mode

The input power will be wired into the N (Neutral) E (Earth) and L (Live) terminals labelled as N E L. Please ensure cables are correct. The receiver supports 80-250v AC.

Live Contact Mode

In this mode we install the LINK between terminal 4 & 5. This will bridge the AC Live power with the (COM) terminal on the relay.

Antenna Connection

The Smartlink comes with an external antenna.  Screw the antenna onto the receiver’s connection in the bottom left corner, below the button trigger.

  • Ensure that the antenna is NOT inside any metal box and is installed vertically as high as possible with the best line of sight to the transmitter unit.

Install Transmitter

  1. Unscrew the 4 screws on top of the lid using a Phillips screwdriver.
  2. Pull out the white battery tab between the battery and metal terminal clip.
  3. You should see the led flash every few seconds, if not twist the battery to ensure it is making proper contact.

Connect the float switch

Install the float switch

There are two operations that can be achieved with the float switch:

Filling using the float switch

  1. Connect the COM wire to the (GND) terminal and NO wire to the (IN1) terminal.
  2. NC wire is not used and must be kept insulated.
  3. Pump will begin to fill and when the water reached the level that makes the float switch float upwards the pump will stop. As the float switch falls it will start pumping again.

Emptying using the float switch

  1. Connect the COM wire to the (GND) terminal and NC wire to the (IN1) terminal.
  2. NO wire is not used and must be kept insulated.
  3. Pump will stop filling the water tank until raises to a certain level (full) will begin filling when it drops low level (empty)

Mounting the Transmitter     

  1. Tighten the 4 screws on the lid ensuring that it has made a uniform seal. Do not over tighten the screws.
  2. Mount the unit vertically so that the cable gland points downwards alongside the tank/reservoir.
  3. Aim the face of the transmitter in the direction of the receiver, make sure there are no objects in the way that can obstruct the signal. The higher the transmitter is mounted the better.

Toggle Button


The relay state can be manually toggled using the push button in the bottom left of the receiver. Once clicked this will trigger the relay on and a secondary click will trigger it off again. Please note that when the transmitter sends its signal it will override the state which the toggle button was in.

Indications and Controls

Technical Details




IP Rating

IP 65


2600mAh (1 Year life Span)


Long Range Wireless

Operating Temperatures

-10°C to 50°C




IP Rating

IP 65

Input Voltage Range (AC)

80v to 250v AC

Input Voltage Range (DC)

45v to 300v DC

Relay Voltage Rating

230v AC or 30v DC

Current Rating


Next SmartLink – DC
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