User`s guide

Chapter 4 ________________________________________________________________ Installation
VAISALA ________________________________________________________________________ 21
CHAPTER 4
INSTALLATION
This chapter provides you with information that is intended to help you
install the DPT145.
Transmitter Configuration Before Installation
Depending on your application, you may need to configure some
transmitter features before physically installing it.
1. By default, DPT145 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 settings for the measured
gas. You can configure the mixing ratio of SF
6
, and the molar
weight of the other gas.
An easy way to configure the measured gas is to connect the DPT145 to
the MI70 indicator using the MI70 connection cable (Vaisala order code
219980). You can change the settings in the Measurement Settings
menu. See Figure 6 below.
1108-039
Figure 6 DPT145 Configuration with the MI70 Indicator
For full configuration options, 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 30.