Vaisala DPT146 - Manual (Page 23)

Chapter 4 ________________________________________________________________ Installation
VAISALA ________________________________________________________________________ 21
CHAPTER 4
INSTALLATION
This chapter provides you with information that is intended to help you
install the DPT146.
Transmitter Configuration Before Installation
You may wish to configure your transmitter before physically installing
it. For easy access to the serial line, use the USB service cable and a
terminal program on a PC. Instructions for using the serial line and the
serial commands are provided in Chapter 5, Operation, on page 32.
Examples of configurable settings for analog outputs:
1. Analog output mode, output parameters, and scaling.
2. Analog output error level.
Examples of configurable settings for RS-485 output:
1. By default, DPT146 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.
Selecting the Location
It is important that the conditions at the point of installation represent
well the gas to be measured. All leaks in the system must be eliminated
to avoid ambient humidity affecting the measurement.
Direct installation to the measured gas is the recommended installation
method if the temperature of the gas is suitable for DPT146 and no
additional filtering is needed due to very dusty or oily gas. Pressure at the