Overview Of The Baseline Pressure Measurement Feature (Channel A); Buttons Used With Baseline Pressure Feature - TEC DG-700 Operating Instructions Manual

1.6 Overview of the Baseline Pressure Measurement Feature (Channel A)

The Baseline feature on Channel A allows the user to measure and record a baseline pressure reading, and then
display the baseline adjusted pressure on the gauge. For purposes of this manual a baseline pressure reading is
defined as a pressure measurement made under a specific operating condition, which will be used to determine the
change in pressure created by a change in the operating condition.
A common building performance application requiring use of a baseline pressure reading is determining the extent of
building depressurization caused by turning on an exhaust fan. In order to accurately quantify the building
depressurization, the user first needs to know the building pressure (with reference to outside) prior to the exhaust
fan being turned on. This initial pressure reading, known as the baseline building pressure, can be quickly measured
and then used to adjust the final building pressure reading (after the exhaust fan is turned on) to determine the actual
change in building pressure caused by fan operation. In the example below, the building depressurization measured
from the exhaust fan operating is –4.2 Pascals (i.e. the building pressure changed from –2.6 Pa to –6.8 Pa when the
exhaust fan was turned on).
Change in Building
Pressure From
Turning On an
Exhaust Fan (Pa)

1.6.a Buttons Used with Baseline Pressure Feature:
Pressing the BASELINE button initiates the baseline
pressure measurement feature. The word
"BASELINE" will begin to flash in the Channel A
display, indicating that the baseline feature is active. At this
point, the gauge is monitoring the real-time Channel A pressure
reading, but is not recording the reading. The Channel B display
is not active at this time.
Press the START button to begin recording a
baseline pressure reading. Once the START button
is pressed, the word "BASELINE" stops flashing and
the gauge begins recording a long term average baseline
pressure reading on Channel A. During the baseline
measurement procedure, the Channel B display is used as a
timer to let the user know how long (in seconds) the baseline
measurement has been active. The longer the measurement time, generally the more stable the baseline reading
typically becomes.
0
-1
-2.6
-2
-3
Baseline
Building
-4
Pressure
-5 (Fan Off)
-6
-7
6
Chapter 1
-4.2
-6.8
Baseline
Adjusted
Building
Pressure
(Change from
Turning Fan On)
Building
Pressure
(Fan On)
Operating Instructions
Feature Summary
for the DG700