Wireless Temperature Installation For Coolers

This tech-tip is meant to give to give some suggestions for installing wireless sensors for applications involving walk-in coolers or freezers.

The MSG O3A wireless sensors communicate via RF (radio frequency) and it is important to note that the metal construction of most coolers and freezers can interfere with radio signal. It is also important to note that the temperatures inside of coolers and freezers can often be below the recommended operating temperature of the batteries used in the wireless sensors. Due to these facts we recommend installing the wireless sensors outside of refrigerated equipment for proper operation. Always refer to the sensor specification for operating temperature ranges to ensure proper operation.

1. Register the sensor in viewmysensors - Do not install the batteries until you are prompted to do so.
2. Determine the sensor's installation location. We recommend placing the sensor in the location and making sure it reports to the gateway before final installation.
   • Some fridges and freezers come with predrilled knockouts that you can punch out to insert the lead. If this is your case, follow the manufacturer’s guidelines on how to do so. After inserting the lead, seal using the manufacturer’s recommendations. If none are available, we recommends sealing the knockout with silicon. See Figures 1–2 to insert the lead and Figure 3 to buffer it.

   •  If your fridge or freezer did not come with a predrilled knockout, you have two choices:

     1. Drill a hole yourself.
     2. Run the lead through the door seal.

   •  If you decide to drill the hole yourself, you need to ensure that the area you choose to drill through DOES NOT contain coils or other vital operating parts. Please check your owner’s manual or other manufacturer’s resources before continuing to drill. MSG is not responsible for damage that may occur by drilling the hole.

     1. After determining hole placement, drill a 0.25” (6mm) hole.
     2. Insert the temperature probe into the hole.
     3. Determine where you are going to leave the probe on the inside.
     4. Affix the probe to the inside.
     5. Seal the hole with a grommet or silicon.