Checking a One-to-One Wireless Sensing System application RF signal strength - Facility Explorer - LIT-12011663 - Wireless Device - WRZ: Wireless Room Sensing System

FX-WRZ Series One-to-One Wireless Room Sensing System Technical Bulletin

Brand
Facility Explorer
Product name
WRZ: Wireless Room Sensing System
Document type
Technical Bulletin
Document number
LIT-12011663
Revision date
2019-04-04
Language
English

About this task

You should verify adequate RF signal strength between sensors and receivers, especially in applications with excessive distances or metal barriers, such as ductwork, concrete with metal reinforcements, equipment rooms, or elevator shafts. The RF signal strength in One-to-One wireless sensing system applications can be checked before you set up your system as follows:

Procedure

  1. Set the DIP switches on the sensor and receiver (or the wireless sensing system tool) to the same RF address (TRANSMITTER ID and AREA).
  2. Use the battery pack of the FX-WRZSST-120 Wireless Sensing System Tool to provide power to theFX-WRZ7860 Receiver (two-pin connector on the back of the FX-WRZ7860, just below the TRANSMITTER ID DIP switch block). See Figure 5.
    Note: The battery pack contains a small power switch.
  3. Hold the FX-WRZ Series Sensor near its desired mounting location in the zone, with the battery installed and the power switch set to ON.
  4. Observe the RF LED on the receiver. Every 60 seconds, an RF transmission occurs and the LED blinks. You can force the sensor into Rapid Transmit Mode (RTM) by pressing the FX-WRZ Series Sensor’s manual occupancy override button for 5 seconds or more.

    In RTM, the sensor transmits a signal every 10 seconds for a period of 5 minutes. After each transmission, the occupancy override LED on the sensor flashes on (one, two, or three times) to indicate the signal strength between the sensor and the receiver. Also, the signal strength LED on the receiver blinks off to indicate the relative signal strength between the sensor and receiver. The LED flashes indicate the following:

    • Three consecutive flashes (of the sensor LED) or blinks (of the receiver LED) every 10 seconds indicate an excellent signal strength.
    • Two consecutive flashes (of the sensor LED) or blinks (of the receiver LED) every 10 seconds indicate a good signal strength.
    • One flash (of the sensor LED) or blink (of the receiver LED) every 10 seconds indicates a weak signal strength. A weak signal strength may result in sporadic loss of data. Therefore, move the sensor and/or receiver mounting locations until the signal strength improves.

      You may need to relocate the sensor or receiver to improve the RF signal reception. The FX-WRZ7860 Receiver may be wired (SA Bus) up to 100 ft (30.5 m) from a supported Johnson Controls controller or anFX-ZFR181x-x Repeater can be installed to extend the range between the FX-WRZ sensor and FX-WRZ7660 receiver.

  5. Check the receiver for adequate RF signal strength after the building occupant moves into the space. Checking a second time ensures that none of the occupant furnishings or equipment interferes with RF signal reception.

Results

See Table 3 for troubleshooting additional problems or symptoms.

Table 1. Troubleshooting One-to-One Wireless Sensing applications
Problem or symptom Cause or action
FX-WRZ Series Wireless Sensor is not associated with the target receiver. (This problem is indicated by no flashes on the occupancy override LED after the manual occupancy override button is released. While the manual occupancy override button is pressed, the LED indicates battery status – on if the battery is good.) The FX-WRZ Series Sensor batteries may be low.

Replace the sensor batteries. Refer to the FX-WRZ Series Wireless Room Sensors Installation Instructions (Part No. 24-10332-37) for information on replacing the batteries.

The sensor and receiver RF addresses may not match.

Check/reconfigure the RF addresses on the sensor and the associated receiver. See Setting the FX-WRZ7860 Receiver RF Address and Setting the FX-WRZ Series Sensor RF Address for more information.

The sensor and receiver may be out of RF signal range, or there may be an RF signal obstruction between them.

Check the RF signal strength and path between the sensor and the receiver using the FX-WRZSST-120 Wireless Sensing System Tool.

The receiver antenna may be positioned poorly.

Reposition the sensor and the FX-WRZ7860 Receiver, ensuring that the antenna symbol is oriented vertically, either up or down.

Recheck the sensor/receiver association at the sensor.

The receiver may have been used with other sensors and does not allow new associations. With power applied to the receiver, change any DIP switch for a few seconds and then move it back to its original position. The receiver resets and erases any former network settings.
The FX-WRZ7860 Receiver may not have power or appears dead (for example, the SA LED does not flicker as expected for SA Bus activity, and the RF LED is off). Verify that the controller is powered and configured as if for a hard-wired network sensor. Ensure that the SA Bus cable is properly connected, or that its plugs are properly crimped. With one end connected to the powered controller, check the plug end that connects to the FX-WRZ7860 Receiver. Pin 6 should be about 15 VDC positive with respect to Pin 5.
Zone temperature and humidity control and/or zone temperature setpoint is incorrect, unreliable, or erratic. The FX-WRZ Series Sensor batteries may be low.

Replace the sensor batteries. Refer to the FX-WRZ Series Wireless Room Sensors Installation Instructions (Part No. 24-10332-37) for information on replacing the batteries.

More than one sensor may have the same RF address as the receiver and set with the same sensor number.

Check the sensor and receiver addresses.See Setting the FX-WRZ7860 Receiver RF Address andSetting the FX-WRZ Series Sensor RF Address for more information.

An obstruction may have been placed in the RF path between the sensor and the receiver.

Check the RF path and signal strength between sensor and receiver.

New RF/Wi-Fi interference may have been introduced into the One-to-One environment.

Check for changes to the RF/Wi-Fi environment and new sources of RF interference.

Two receivers may have duplicate RF addresses and overlapping signal coverage with associated sensors.

Check for duplicate RF addresses and ensure there is no signal overlap in applications with duplicate RF addresses.

Wiring between the receiver and the controller may be incorrect or damaged.

Check the wiring between the receiver and the controller.

Sensor may be defective or damaged.

Turn off the suspect sensor and configure a new sensor with the receiver address; then, check the operation of the new sensor with the receiver.