Risco ProSYS Plus - Measuring Background Noise Level and Defining Its Threshold Limit

09/2016 Page 45 5IN2371 C
Measuring Background Noise Level and Defining its Threshold Limit
If the system uses wireless devices, you can measure (“calibrate”) the background
noise that the main panel detects, and also define the acceptable threshold value.
Background noise (RF interference) is typically generated by other non-system
devices operating in close proximity to the system, and high amounts may
interfere with the system, causing “jamming.” Communication between your
system’s wireless devices (via wireless expander module/s) and the main panel
must be stronger than any detected background noise at the main panel, therefore
regardless if the current level of background noise the panel detects seems
insignificant, it is recommended to additionally perform a Wireless
Communication Test, to check a wireless device’s signal (see Performing a Wireless
Comm. Test for Measuring Signal Strength, page 46).
Measuring the background noise level provides an indication whether the main
panel is mounted at a good location, and defining the threshold limit value enables
you to determine how much background noise your system will tolerate before it
generates jamming events. The lower you define the threshold value, the more
sensitive the system will be (it will report jamming events more frequently), and
the higher you define the threshold value, the less sensitive the system will be (it
will report jamming events less frequently).
 To calibrate (measure) the background noise:
1. From the installer Programming menu, select 7 > 2 > 1 (Install >WL Device >
RX Calibration); CHOOSE RECEIVER (wireless expander) displays.
2. Scroll to select the wireless expander module, and then press OK ( ); the most
recently measured result (“THOLD”) for that wireless expander module
displays.
3. To re-calibrate (re-measure) the background noise, press to toggle to Y
(yes), and then press ; the new result (“NEW THOLD”) displays.
4. Press to confirm. If the resulting value is not acceptable, for example if it is
high due to what you believe is a source of high background noise that’s
inherent to the main panel’s location, then you may want to move the main
panel to a better location. Another option you may consider is to re-define the
noise level threshold value (see below) – for example, so the system will be
more “forgiving” and generate less jamming events.