Moore Industries TDZ, Руководство по установке

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The Interface Solution Experts 19
THZ & TDZ
Operation
Once programmed, calibrated, installed, and supplied
with the correct power, THZ and TDZ transmitters
begin to operate immediately. Depending upon envi-
ronmental conditions, they can be expected to operate
unattended for extended periods of time.
HART Protocol
This section of the manual gives an overview of the
HART format used by THZ and TDZ modules during
operation. Use the information in this section to pro-
cess the data provided by the module(s) during opera-
tion. For more information on the HART protocol,
contact the HART Foundation at:
The HART Communication Foundation
9390 Research Blvd, Suite 1-350
Austin, TX 78759-6540 U.S.A.
(512) 794-0369
www.ccsi.com/hart
Device Types
To implement two-way communication between the
THZ and the device being used to configure it or re-
ceive its information, the THZ or TDZ operates in a
HART Master/Slave structure. The THZ or TDZ is the
Slave (or slaves in a multidrop network).
There can be two Masters per system: a Primary
Master and a Secondary Master. Masters are typically
either a HART Hand-Held Communicator or a HART-
based control system.
In many applications, the Primary Master is a HART
Hand-Held Communicator. The communicator is
used solely as a configuration tool to set up the
transmitter, periodically view its real-time process
measurement, or view its operating and diagnostic
information from a loop termination point.
Digital Signal
One of the advantages of the HART protocol is that
the digital information is conveyed by the same wires
used to output the 4-20mA signal. After being polled
by the master, the THZ or TDZ responds to the inquiry
by modulating the 4-20mA current 0.5 mA above or
below the output signal. 1200 Hz represents 1 and
2200 Hz represents 0.
Communication Speed and Format
The speed of the HART transmission is 1200 baud.
The time delay between a master initiating a request
for data from a slave and the slave receiving and ac-
knowledging the request depends upon which com-
mand is issued. Generally, a master can poll a slave
2-3 times per second.
The byte structure of the HART signal is:
1 Start Bit, 8 Data Bits, 1 Odd Parity Bit, 1 Stop Bit.
Maintenance
Moore Industries suggests a quick check for terminal
tightness and general unit condition every 6-8 months.
Always adhere to any site requirements for pro-
grammed maintenance.
Customer Support
Moore Industries is recognized as the industry leader
in delivering top quality to its customers in products
and services. We perform a battery of stringent qual-
ity assurance checks on every unit we ship. If any
Moore Industries product fails to perform up to rated
specifications, call us for help. Our highly skilled staff
of trained technicians and engineers pride themselves
on their ability to provide timely, accurate, and practi-
cal answers to your process instrumentation ques-
tions.
Factory phone numbers are listed on the back cover of
this manual.
If problems involve a particular THZ or TDZ, there
are several pieces of information that can be gath-
ered
before you call the factory that will help our
staff get the answers you need in the shortest time
possible. For the fastest service, gather the com-
plete model and serial number(s) of the problem
unit(s) and the job number of the original sale.