-2-
b)
The HHM interacts with you to SETUP
operating parameters to match your installation. It
stores these parameters in non-volatile memory. You
can then SEND these parameters to the AQT-2000.
The HHM can also LOG data from the AQT-2000
and later DUMP it to a personal computer. The
HHM is only used for SETUP and LOGGING of air
quality. It has no monitoring or control function and
can be disconnected from the installation once the
AQT-2000 is programed. It is powered by the AQT-
2000.
c)
The demo kit contains a 4 to 20mA analogue
panel meter connected to the current output of the
AQT-2000. In a typical installation this 4 to 20 mA
signal would be fed directly to a damper actuator to
control its position.
The power supply powers the AQT-2000. It can be
plugged into any 110V outlet to operate the
demonstration kit. In permanent installations the
AQT-2000 requires a 12 to 30VDC power supply.
d)
The hand held module has a serial output that
can be attached to the serial port of an IBM
compatible PC or Macintosh computer. We offer a
package containing a data download cable which
powers a hand-held module and connects it to a PC
to download stored data to the graphing package we
supply.
You can also use your own communications,
graphing and spreadsheet software for complex
analysis.
If you have a real-time graphical package you can use
the supplied “Y” cable to connect the AQT-2000 and
the HHM-AQ to your PC to monitor and save air
quality data in real-time.
If you will be using a Macintosh computer you will
need to extend the supplied cable with a null modem
connector and a MAC serial modem cable. We
suggest you use Claris Works for communication
and graphing or use the charting software we supply
under Soft Windows.
3.
PROGRAMMING
The AQT-S-420 and AQT-D-420 are factory
calibrated and programmed before delivery to the
customer. The analogue output changes
proportionally to pollution level. If a 4-20mA output
has been chosen 4mA represents the best possible air
and 20mA represents the worst.
We use medical air to calibrate the 4mA setting.
Readings this good will not normally be achieved in
operating conditions. Readings of 8mA or less
indicate excellent indoor air quality while 16mA or
more is poor.
In general practice anything less than 1/3 scale
(9.3mA) is usually considered very good and not in
need of any action. Between 1/3 and 2/3 scale
(14.6mA) progressive stages of filtering or cleaning
are employed to improve air quality. Sufficient fresh
air is normally introduced to prevent air quality
readings exceeding 2/3 scale (14.6mA).
Although the air quality monitor is ready for
operation as received from the factory the available
hand held module serial kit are valuable tools to log
and graph air quality data to determine if and where
air quality monitors should be used. the hand held
module can also be used to reconfigure
or recalibrate an air quality monitor.
The following section describes the use of the hand-
held module and graphical software. If you are
simply installing an air quality monitor you can skip
to section 6, which describes wiring hook up.
When powered on the HHM will display:
SELECT FUNCTION
SEND flashing
As you press the up/down arrow key SEND will
toggle to SETUP, DUMP , LOG and back to
SETUP
The first time the HHM is used press the up/down
arrow key until SETUP is displayed. Then press the
green enter key.
The unit will display:
HOW WILL AQT BE USED
TRANSMITTER flashing
As the up/down arrow key is pressed
TRANSMITTER toggles to CONTROLLER and
back again. Press the green ENTER key to select
your choice.
CONTROLLER should be chosen for use in a
portable classroom or similar application where the
AQT will monitor the conditions in a single room and
directly control a fresh air damper to maintain air
quality. In this mode the AQT reacts very quickly to
changes in air quality so it can provide additional
fresh air as more occupants enter a room or the
activity level increases in the room.
TRANSMITTER should be chosen if several AQT’s
will send an analogue signal representing air quality
back to a central control system which will perform
the control function. In this mode the air quality
monitor produces an analogue output signal
proportional to a user defined section of the air
quality spectrum.
If you choose CONTROLLER go to A
If you choose TRANSMITTER skip section A and
go to B
