Vaisala DRYCAP DMT143 - Installation; Configuring Transmitter Before Installation

4. Installation
4.1 Configuring Transmitter Before Installation
You may wish to configure your transmitter before physically installing it. For easy access to
configuration options, use either Vaisala Insight PC software with the USB service cable
(Vaisala order code 219690), or connect to the serial line using the USB service cable and a
terminal program on a PC.
Some configuration settings can also be changed using the DM70 handheld meter.
Examples of configurable settings for analog output:
1. Analog output parameter and scaling.
2. Analog output error level.
Examples of configurable settings for RS-485 output:
1. By default, DMT143 transmitters are configured for single transmitter operation. Serial
operation mode is STOP and address is 0.
To configure transmitters for operation on a common line, you must give each transmitter
a unique address (range 0 ... 255) and set their serial operation mode to POLL.
2. The default serial line settings may not be right for your RS-485 line.
3. You may need to change the transmitter’s serial output format to suit your needs.
More Information
‣
Vaisala Insight Software (page 36)
‣
Operation with DM70 Handheld Dew Point Meter (page 38)
‣
Connecting to the Serial Interface (page 41)
4.2
Selecting the Location
It is important that the point of installation represents well the gas to be measured.
Temperature changes do not aect the dew point measurement, but pressure changes will
have an eect on the measurement. All leaks in the system must be eliminated to avoid
ambient humidity aecting the measurement.
Direct installation to the measured gas is the recommended installation method if the
temperature of the gas is suitable for DMT143 and no additional filtering is needed due to very
dusty or oily gas. Oil as such is not harmful for the DRYCAPâ sensor, but response time may
be slower if there are oil particles in the system, or if oil is collected to the filter over a longer
period of time. The maximum measurement pressure is 50 bar
a
/ 725 psi
a
(absolute pressure)
for direct measurement.
DMT143 User Guide M211435EN-J
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