Example layout - Johnson Controls - LIT-12013954 - JC-TMR2400-x - Wireless Device - TMR Series Wireless Best Practices

TMR Series Wireless Best Practices

Johnson Controls
Product name
TMR Series Wireless Best Practices
Document type
Commissioning Guide
Document number
Revision date

In this example, a typical small warehouse with multiple air-cooled chillers is examined. The goal is to determine whether the layout is a good TMR wireless candidate, the placement of the CEG Panel and whether TMR repeaters are required.

Step 1

Identify the site and the equipment that will be monitored by the CEG.

Figure 1. Identifying the site

Step 2

Draw a simplified scaled outline of the site. Indicate the locations of the chillers and the intended location of the CEG Panel.

Note: Items to consider for the CEG Panel location include:
  1. Good cell coverage
  2. Access to 120 VAC power
  3. Solid mounting surface
  4. Distance to wireless equipment

In this example, the CEG panel location was chosen to be on the North corner of the building because of items 1 and 2 above. Choosing a location near the center of the building would have been more ideal from a wireless equipment perspective, but more costly to run power and mount the panel.

There are 8 chillers in this example, so you need two PANs. A second TMR will need to be ordered and installed into the panel.

Depending on the chiller type, you may also need to order and install outdoor enclosures to mount the TMR’s onto the chillers. In this example, the TMRs will be mounted in the plastic outdoor enclosures so the transmission range can be maximized.

Figure 2. Drawing of a simplified scale outline of the site

Step 3

Draw a range circle around the Coordinator. In this example, the TMR are models that have a 250’ range. Adjust the diameter for other models if required. If the TMRs are going to be mounted inside the chiller control enclosures, you may also need to decrease the radius to account for the attenuation due to the metal enclosure. A good rule of thumb would be a 25% reduction.

Note: If you chose to reduce the range circle for one of the installation locations, all the ranges should be reduced.
Note: There are three chillers within one hop of the coordinator.
Note: Assign two of the chillers to PAN1 (yellow) and the other to PAN2 (blue).
Figure 3. Range circle around the Coordinator

Step 4

Working on PAN1, draw a second range circle around the outer chiller in PAN1. Highlight additional chillers to assign to PAN1 (yellow). Since the design limit is four controllers per PAN, only two of the three available chillers are highlighted.

Note: All of the chillers assigned to PAN1 are 1 or 2 hops from the coordinator.
Figure 4. Second range circle around the outer chiller

Step 5

  1. Continue analysis work with PAN2.
  2. Assign the additional 3 chillers to PAN2 (blue).
  3. Draw a range circle around the outer RTU in the first hop of PAN2.
Figure 5. Second range circle around the outer chiller

Step 6

Note: Not all the chillers fall into this second range circle, add another circle by choosing an chiller within the second range circle. In Figure 6 , all chillers are now covered within 3 hops of the coordinator.

The conclusion is that these two PANs with the chillers assigned as shown should have good coverage. No additional repeaters will be required.

Figure 6. Chillers covered within 3 hops of the coordinator