Azbil AVP200, Руководство пользователя

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Chapter 1: Control System Structure
1.2 Travel Transmission Output (Models AVP301 and AVP201)
This device (models AVP301 and AVP201) has the ability to transmit the position of
the control valve. The device’s travel transmission system offers two output formats,
depending on the purpose. There is a system that outputs an analog signal and a system
that outputs a digital signal.
■
Analog output
To output the position only to the host monitoring device using a analog values, set up
the analog output system. Normally, the range from the fully closed position to the fully
open position is output as a 4–20 mA range.
■
Digital output
To output the position along with a variety of device settings and self-diagnostic results
to the host monitoring device, set up the digital output system.
■
Output format switching
The output format provided by the device is specified by the user as configuration data
when ordering the device. The device is set at the factory to either analog output specifi-
cations or digital output specifications.
Note, however, that the output format can be switched freely by the user using the Com-
mStaff CFS100 field communication software or the HART
®
Communicator.
1.2.1 Structure of system without travel transmission output
This figure shows the system structure of the device when the travel transmission func-
tion is not used.
Main Unit
HART
®
Communicator
(Models AVP302 and AVP202 only)
or CommStaff
CommStaff
Host
controller
4–20 mA DC
Figure 1-2. Structure of System without Output (Model AVP300, AVP302, AVP200, and AVP202)