25
Revision
Before the zeroing, verify that the pressure range for operation, and the type of output signal to the VSD, are correct.
The pressure range shall be 0-100Pa, "pressure" should be displayed in the screen, and the output signal shall be
4-20mA.
Following the description in fi gures below, open the cover, and press the “
▲
”, “
▼
” or “OK” buttons on the back once.
Press “
▲
” or “
▼
” to change the measurement range to 0 ..+100Pa. The selected range fl ashes on the screen until it is
memorized by pressing the "OK" button. If the button is not pressed again within the next 60 seconds, the display reverts
to the current measured value.
Verify that the SW1 micro-switches, framed in the fi gure with a dotted line, are in the following positions:
• DIP3 OFF (display pressure)
• DIP2 OFF (damping 0.4 sec)
• DIP1 ON (4-20mA)
Zeroing
The transducer can be calibrated after it has been mounted and the power supply connected (the latter will lit the green
LED). Before calibration, it is important to ensure that the pressure at the + and - connectors is the same (for example
by stopping the fan). If a pressure differential greater than 10Pa is shown on the screen, this could be caused by an
unexpected pressure within the system (drafts or obstructed tube). It is recommended that the
external
tubes of the
PDS CONTROL be disconnected from the + and - connectors during calibration.
For zeroing, press switch SW3, integrated in the electronic board (see fi gure), then the yellow LED will blink until cali-
bration has been completed.
LED
ON
Blinking
OFF
Green
OK
No supply
Yellow
Calibration in process
A length of more than 30m is not recommended for external connection tubes.
For more information, see the TDP-D pressure sensor instructions manual.