Retrotec FanTestic (ATTMA) - Manual (Page 36)

rev-2014-10-27
Page 36 of 58
©Retrotec Inc. 2011-2014
You can adjust the [Time Avg] function of your gauge to ensure that proper averaging occurs during the
manual readings.
5.10 Induced Pressure data lines [Pa]
Enter the induced pressure, as read from the gauge (PrA on the gauge). This is the test pressure created
in the building as a result of the door fan running.
The ATTMA states that there must be a minimum of 10 Induced Pressures while pressurizing, and 10
Induced Pressures while depressurizing, between 15 and 60 Pa. Each induced pressure must be
measured over at least 20 seconds.
You can adjust the [Time Avg] function of your gauge to ensure that proper averaging occurs during the
manual readings.
When manually entering data into FanTestic, set the time averaging on the gauge to at least 20 seconds
for induced pressure and flow readings. This must be done in order to compensate for the effects of
wind and to ensure that you get an average reading. On windy days you will have to take readings for a
longer period of time. To determine if it is windy, set your gauge 25 second averaging and check if the
pressure fluctuation is above 2 Pa. If so, double the time averaging for the induced pressure and flow
readings to 40 seconds.
On the DM32, tap Channel A to activate the Hold feature so the readings don’t change while you’re
writing them down.
If more than one fan is used for the test, automatic mode must be used, since the average building
pressure is to be used for ATTMA, and must be entered and calculated for each fan.
If the variation of induced pressure at any of the fans is out of compliance, those cells are highlighted in
red background:
5.11 Test Fan Data lines
Data readings from each fan are specific to the range configuration installed on the fan when the
pressure or flow is read from the gauge. A Fan Pressure Line must be added in the set for each
fan/range combination used during the test (if ranges have to be changed during a test to reach the
required induced pressure).