Beacon Mode:

Beacon Mode provides a very fast communication back to the MirC Sender, indicating relay status. The drawback to this mode is that it generates more radio traffic, so it consumes more power. However, relay status information is displayed on the sender in one second or less. In beacon mode, the relay status will not change if communications is lost between the relay controller and the sender.

Smart Mode:

Smart mode waits for the next communication cycle to report the status of the relay. Relay status information will be available to the sender device within 3 seconds. This mode consumes less power and generates far less radio traffic. Smart mode is recommended for most applications if you can tolerate a 3 second delay. In smart mode, the relay will turn itself off automatically if communications is lost between the relay controller and the sender.


MirC devices are only sold as a permanently married pair, pricing shown on our web site indicates pricing for the pair of controllers. Contact Closure Inputs may only be connected to switches, buttons, or sensors with Contact Closure capability. Not suitable for use in voltage detection applications. MirC devices use 802.15.4 two-way communications to ensure the remote device is properly functioning. The Busy LED is always used to indicate a properly functioning remote device. If you do not see the Busy LED flash, then the MirC controller is unable to communicate to the remote device. A flashing busy LED is your verification that all communications are functioning properly between MirC controllers.

Customers who require inductive switching (such as motors, lights, pumps, solenoids, and Transformers) should visit the Induction Suppression portion of our web site.


The distance between MirC controllers will affect reliable operation. MirC controllers will offer better range if two MirC controllers are within line of sight of each other. If it is not possible for 2 MirC controllers to see each other, more expensive communications options will improve working distance for most users. You can expect MirC devices to function properly in most applications between 300 feet and up to 15 miles depending on communications module and antenna options chosen. MirC controllers are available with 3 options. The default option is the "Standard Range", which operates up to 300 feet and includes a small integrated antenna that cannot be moved or positioned. The "Mile Range" Option offers communication between devices up to 1 mile apart (line of sight) and includes a small external antenna. The "15-Mile Range" Option operates up to 15 miles (line of sight) between controllers. This is our most expensive option, which includes TWO Roof Mount antennas, 20 Feet of Cable for Each Antenna, and 2 cable adapters. Hills, Trees, and Buildings will greatly reduce communication range of all wireless devices, so practical distances may be less.

Product Variations: MirC and MirX Series Controllers

NCD Currently offers 2 variations of this design: MirC and MirX.

MirC: Transmitter Controller and Receiver Controller. The Transmitter Shows the Status of Relays on Receiver Controller. The Transmitter is equipped with Contact Closure Inputs and Remote Relay Status LEDs. The Receiver is equipped with Relays and Relay Status LEDs.

MirX: Each Controller is a Transmitter and a Receiver. The Inputs on One Controller control the Relays on the Opposite Controller. Relay Status is Shown using LEDs on Each controller.

MirC controllers include two circuit boards. The "Local" and "Remote" circuit boards work together to control relays at the remote location from the controller in the Local location. The Local Circuit board has contact closure inputs. When an input change is detected on the Local circuit board, the relay is changed on the Remote circuit board. The Remote Circuit board sends feedback to the Local controller. The LEDs on the Local controller display the status of the relays in the Remote location based on 2-way communications. If communications is lost between the devices, the Remote relay will turn off (If set to Smart Mode). The relay status LED on the Local controller will also turn off. The Remote relay controller is also equipped with LEDs to show the status of the relays. Relay status can be seen on BOTH controllers.

MirX controllers also include two circuit boards. Each controller is a Transmitter and a Receiver, each controller is equipped with contact closure inputs and relays. The local contact closure inputs control the relays at the remote location and vice versa. The LEDs on each controller display the status of the relays ONLY.

Solid State a Practical Alternative to Mechanical Relays

Mechanical Relays have a good home in low-cost control applications. But for some users, only solid state switching will do. Solid State Relays are ideal for users who require long term reliability, silent operation, or high induction tolerance. Many inductive control applications require a solid state relay. Inductive loads such as Motors, Valves, Pumps, Solenoids, and Large Transformers (including Fluorescent Lighting) benefit from the use of solid state relays because they reduce the chances of the inductive load interfering with the logic of the relay controller.

You can purchase this controller with the relays installed two ways.  You can have your choice of the same solid state relay installed in this board or you can choose different relays to be installed in each relay location.  Simply choose the controller with _MIX in the part number and you will be able to choose specific relays for each location.  If this controller is not a _MIX you can find it listed under Related Products on the right side of this page.

Attention: No Voltage Input

Please Note: Users must NEVER apply any voltage to an input on the Mir-C controller, these inputs are for Contact Closure connections only.