YOKOGAWA RAMC, User Manual

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<7. HART-COMMUNICATION>
7-1
IM 01R01B02-00E-E 12th edition October 01, 2014 -00
All Rights Reserved. Copyright © 2003, Rota Yokogawa
7.1 General
RAMC with indication unit type -H have, additional to the current output, the possibility for HART
®
-
Communication. Also without HART
®
- Communication the units are fully able to work. The HART
®
-
Communication does not influence the current output, except in Multidrop-Mode (see below).
There exists no difference between the not-Ex and the Ex versions. For use in the hazardous area a HART
®
-able
transmitter power supply is required.
The HART
®
-Communication is only available with plugged calibration-EEPROM
The HART
®
-Communication is only available for 2-wire units, 4 ... 20mA. Therefore the short-circuit bridge must
be connected between ´ A ´ and ´-´.
7. HART
®
- Communication
NOTE
NOTE
Deviations in the RAMC- Menu
In HART
®
devices the operating menu according chapter 6 is not available.
Pressing the
↑
-button the indication can be changed between flow, totalizer and temperature.
Factory default is totalizer.
Pressing
→
button an error indication appears on display.
00000000 or 00000000
A detailed explanation see chapter 7.4.2 .
7.1.1 Multidrop Mode in the case of using HART 5
“Multidropping” transmitters refer to the connection of several transmitters to a single communication
transmission line. Up to 15 transmitters can be connected when set in the multidrop mode. To activate multidrop
communication, the transmitter address must be changed to a number from 1 to 15. This change deactivates the
4 to 20 mA analog output, setting it to 4 mA. The alarm current is also disabled.
Setting of Multidrop Mode
Device Setup
Detailed setup
Device Information
Poll addr Enter the number from 1 to 15(Def.: 0)
Enabling the Multidrop Mode
About the procedure to call up the Polling display, please refer to the User’s Manual of
each configuration tool.
When the same polling address is set for two or more transmitters in multidrop mode,
communication with these transmitters is disabled.
Communication when set in multidrop mode
The HART configuration tool searches for a transmitter that is set in multidrop mode when
it is turned on. When the HART configuration tool is connected to the transmitter, the
polling address and the tag will be displayed.
Select the desired transmitter. After that, normal communication to the selected
transmitter is possible. However, the communication speed will be slow. To release
multidrop mode, call up the Poll addr display and set the address to “0”.
NOTE