ICAM by Xtralis
ICAM ILS-2 Product Guide
www.xtralis.com
21
6.3
Parameters
The Fan Speed, Flow Limits and Flow Sensitivity need to be set for each installation prior to Flow Calibration
and testing. The following guidelines will assist in the commissioning of the unit.
6.3.1
Fan Speed
The Fan Speed should be set as high as possible to achieve the fastest transport time from the sampling point
to the detector(s), which is especially important for longer pipe lengths and for installations that must conform
to the requirements of EN54-20 (please refer to Section 4.8). However, a balance also needs to be achieved
between performance and power requirements - please refer to current consumption figures in Table 11-1 prior
to setting this value.
6.3.2
Flow Delays
When airflow limits are exceeded, a Flow Fault will appear after a programmable Flow Delay time. The default
Flow Delay time is approximately 30 seconds. Once the airflow returns to a normal level, the fault condition
will be cleared within 18 seconds. Available settings for Flow Delay are shown in Table 6-2.
In environments where the sampled airflow may be affected by sudden temperature or pressure changes or if
there is a risk of physical interference of the sampling point (e.g. prison cell applications) then it may be
necessary to increase the Flow Delay time.
Table 6-2: Flow Delay Settings
Bargraph
LED
Flow into Fault
Delay (Seconds)
Flow out of Fault
(Seconds)
0
15
2
1
30
18
2
60
18
3
90
18
4
120
18
5
150
18
6
180
18
7
210
18
8
240
18
9
270
18
Notes:
l
Timings are approximate.
l
The default flow delay setting is 1.
6.3.3
Flow Sensitivity
This setting determines the units responsiveness in reporting blocked sampling points or broken pipes.
The default flow sensitivity value of 9 will configure the unit to declare a flow fault whenever there has been a
change in volumetric airflow of ± 20% from the calibrated reading for at least the duration of the flow delay, see
Section 6.3.2. For most installations, especially if compliance with EN54-20 is required, the default setting
should be used.
In certain circumstances, such as rapid changes in ambient air pressures due to air handling units, doors
opening/closing etc. the default setting may appear to be too sensitive. Under these conditions, the flow delay
setting should be increased to allow time for the air pressures to stabilize after the temporary event.
Only under extreme environmental conditions or non standard pipe configurations should decreasing the flow
sensitivity be considered.
