
Startup
The AFA500 must be eld-calibrated once the
room air supply and exhaust is balanced. When
the unit is powered up, the following sequence
of events occurs:
1. The alarm performs a self-test of its
functions, LEDs and audible alarm
(approximately 2 seconds) and then initiates
a delay timer of 30 seconds to allow the
airow sensor to stabilize.
2. During the 30-second stabilizing period, all
alarms and relay outputs are deactivated and
the red and green LEDs remain on.
3. At the end of the delay, the unit will do
one of two things:
a. If the monitor has been calibrated,
the unit enters normal operating mode (solid
green light for safe velocity, red light and
audible alarm if low velocity).
b. If the unit has not been calibrated,
the red and green LEDs will ash, the audible
alarm will be muted.
Installation &
Calibration Guide
Airow Monitor
AFA500 MK2
Calibration - Single Point (default)
1. Determine the required low air alarm point, then position the sash
and use a calibrated instrument so that the face velocity is equal to
the required alarm point.
2. Press and hold the ENTER button for 5 seconds to enter Calibration
Mode. This is indicated by both red and green LEDs ashing with
the audible alarm beeping.
3. To initiate calibration, press and hold the ENTER and SET buttons
at the same time. The unit will sample the airow for 5 seconds,
during which time the green LED goes o and the red LED ashes.
The audible alarm continues to sound during the air sampling.
4. If calibration is successful, the monitor will give a two-tone beep at
the end of the air sample, and then automatically enter run mode.
5. If the ENTER or SET button is released during the air sampling
period, or if the airow is uctuating too much, the alarm will emit
a lower-frequency buzzing for a short period and then re-enter
calibration mode. If this occurs, press the ENTER and SET buttons
again to repeat the airow sampling.
6. When the calibration is complete, lower the sash to the normal
operating height and the Green LED should be illuminated,
indicating that the airow is greater than the calibrated alarm point.
If, during normal operation, the airow drops below the alarm
point, the unit will go into alarm condition (red LED ashing, audible
horn beeping). Push the enter button to temporarily mute the horn.
7. The horn can be permanently disabled by pressing and holding the
SET button for 10 seconds. The horn will sound 3 times to indicate
that it has been disabled. In Safe mode the Green LED will ash if
the horn is disabled or be solid to indicate that the horn is enabled.
To enable the horn press and hold the SET button for 10 seconds,
the horn will sound 3 times to indicate that it has been enabled.
Temperature Electronics Ltd. Unit 2, Wren Nest Road, Glossop SK13 8HB UK
T.
+44 (0) 1457 865 635 F.
+44 (0) 1457 868 843 E.
[email protected] w. www.tel-uk.com