Selecting The RS-232 Interface

By selecting the RS232 interface you will be sending commands to the board through either a DB9 or direct wire interface. Boards on this page are equipped with a ZRS communications module that adds RS-232 communications to the board. At checkout you will have three modules to choose from with either a DB9 or direct (3-wire) connection. A command consists of a few bytes of data in numerical format usually between 2 and 6 bytes. Once the command has been received, the controller processes the command and the relay activates.
Selecting an RS232 Relay Board
Below you will find the RS-232 Relays that are available. The difference being the amperage of the relays installed and the type of relay. Choose the controller that fits the amperage you are switching. You will find SPDT relays in the 5, 10 and 20 amp versions and an SPST version in 30 amp. DPDT versions are also available with 1, 3 or 5 amp relays installed. For more information on selecting the correct relay for your application see
Choosing a Proper Amperage>.
Selecting an RS232 Relay Series
RS-232 Relay boards are available in Pro, ProXR Lite and ProXR versions. The Pro versions offer a no-frills design that's fully EC3 compliant and the Pro Firmware installed - a smaller command set than our full ProXR and ProXR Lite models . ProXR and ProXR Lite versions have the ProXR firmware installed and accept the full ProXR command set, the industry leading command set for controlling relays. The ProXR Lite version is non-expandable, the ProXR version is expandable to 256 relays. When you find your controller click on the Full Description link to view full specs, watch setup videos, download software and purchase.