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Atmospheric pressure equilibrium
As soon as you receive the instrument, it will be necessary to ensure the interior and exterior of the
instrument are both at the same atmospheric pressure. It is probable that during shipment these
pressures will become different.
To ensure the pressures are equal, simply press the pressure relief valve located on the top of the
instrument (No. 5 in
on page 6) for about 5 seconds before releasing.
Connections
Flow chamber
The flow chamber’s sample inlet (N° 1 in
on page 6) and outlet (N° 4 in
use ¼-inch diameter transparent plastic tubing. Connect by compression fittings to the sample
source and to the drain, respectively.
Control the sample flow using the adjustment valve (No. 2 in
on page 6) located on the front
of the flow chamber.
If ordered, you will also have received a model 32051 sample tube adapter to attach the flow
chamber inlet tubing to the sampling point.
Instrument - PC connection
An RS-232 cable is supplied with the instrument, with a 6-pin LEMO plug on one end and a 9-pin D-
Type plug on the other.
Connection
LEMO-6 Pin
Description
Pin 1
Transmitted data (TXD)
Pin 2
Received data (RXD)
Pin 3
CTS
Pin 4
RTS
Pin 5
Not used
Pin 6
Ground
Pin 1
Not used
Pin 2
RS-232 Transmitted Data (TXD)
Pin 3
RS-232 Received Data (RXD)
Pin 4
Not used
Pin 5
Ground
Pin 6
Not used
Pin 7
Request to send RTS
Pin 8
Clear to send RTS
Pin 9
Not used
Note: If you use an adapter for the connection to the PC, make sure it is designed for this purpose and, thus, has
all nine pins accessible. Some 25-to-9 pin adapters are supplied for specific use, such as a mouse, and these may
have only certain pins available.
It is not necessary to keep the PC connected to the instrument during measurement. This connection
is required for downloading stored measurements, real-time monitoring, reviewing and changing
configuration parameters and testing the instrument from the PC.
External power supply (optional)
The instrument is usually powered by the batteries supplied. You can, however, power it from an
external power source using the model 32939 power supply adaptor as illustrated in
English
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