CDVI Radio Receiver, 2 Relays, LCD Display, 433.92MHz RX26-XPL

What this receiver does

A receiver listens for a signal from a hand-held transmitter and closes a contact when it hears a code it knows. That contact then tells a gate, door or light control to act.

This CDVI receiver is aimed at sites where settings change now and then. Everything can be seen and changed on the unit, with no separate programmer needed for general setup.

How it works

• Rolling code: the code sent by the transmitter changes each time. As a rule, this makes a recorded signal far less useful to anyone trying to copy it.
• Pulse: the relay closes briefly, which is what most gate and door controls expect as a start signal.
• Step: the relay changes state with each press and stays there, which suits something like a light that is switched on and off.
• Timed: the relay stays operated for a set time, then returns. The relay time is one of the settings made from the push buttons.

Where to use it

It suits a building, a comms cupboard or a gate control room, because it is for internal use only. It is not the right choice to fix bare on a gate post.

Check the temperature of the space too, as the working range is -20°C to 70°C. That is rarely a problem indoors, though a sealed cabinet in full sun deserves a second look.

What the figures mean in practice

• 24VA on a relay: this is a low power limit meant for signal and control wiring. Anything heavier, such as a motor or a mains load, should be switched through its own controller or a suitable relay.
• Consumption: the figure is a range with a maximum. Allow for the top figure when adding it to an existing supply.
• Two relay types: only one relay offers a normally closed contact. Use that one if the device you are driving needs a contact that opens to signal.

Installing it

• Position: keep it away from large metal cabinets and heavy electrical equipment, as both can cut radio range.
• Supply: both AC and DC are accepted, so a spare low voltage output on a gate or door control is often worth checking first.
• Back up the settings: once a site is programmed, saving to the external memory device gives you a copy for restoring the site or setting up a new receiver.

Planning your system

You will also need hand-held transmitters, a low voltage supply and the door or gate control the relay will trigger. Check that each transmitter states 433.92MHz and Keeloq rolling code.

A receiver only gives a start signal. Safety devices on an automatic gate, such as photocells and safety edges, belong to the gate system and need their own design.