Micro Motion Manual: Remote Flow Transmitter - Model RFT9729 | Micro Motion Manuals & Guides
March 1991
Rosemount, SMART FAMIL~ and HART are trademarks of Rosemount Inc.. Eden Prairie. MN.
Hastelloy is the trademark of Gabot Gorp.. Kokomo. IN.
Teflon is the trademark of E.I. Du Pont de Nemours Go. Inc.. Wilmington. DL.
1991. Micro Motion. Inc
All Rights Reserved
Tables
Table 1
Table 2
Figures
Figure 1-1
Figure 2-1
Figure 2-2
Figure 2-3
Figure 2-4
Figure 2-5
Figure 3-1
Figure 3-2
Specifications AFT 9729 to OMS Wiring,
Mounting Dimensions 8
Back Panel Connections 10
Wiring Diagram for the D6 through D300 14
Wiring Diagram for the D600 15
RS-485 Wiring 17
HART Network Wiring 18
Location of Jumpers and Test Points on the Processor Board 20
Changing the Jumper Settings 20
3
16
Table of Contents
1
1.1
1.2
1.2:1
1.2.2
1.2.3
1.3
1.4
1.5
1.5.1
2
2.1
2.2
2.3
2.4
2.4.1
2.4.2
2.4.3
2.5
2.5.1
2.5.2
2.5.3
2.5.4
2.5.5
2.5.6
3
3.1
3.2
3.3
3.4
3.5
3.5.1
3.6
3.6.1
3.6.1.1
3.6.1.2
3.7
The Remote Flow Transmitter General Description Theory of Operation Communication Fault Detection and Diagnostics Meter Zeroing Independent Exchange of Flow Sensors and Transmitters.
Modular Electronics Display Totalizer Reset Button
Transmitter Installation 9
General 9
Installing the Transmitter 9
Power Connections 10
Signal Wiring; Sensor to the Transmitter 11
Cable Connections 11
Sensor Conduit Connections 12
Intrinsically Safe Wiring Requirements 12
Transmitter Output Wiring 12
Analog Output Wiring 12
Frequency Output Wiring 13
Flow Direction Wiring 13
DMS Wiring 13
RS-485 Wiring 16
Multidrop Wiring for the Milliamp Output 16
Start-Up 19
Jumper Configuration on the Processor Board 19
Power. 21
Transmitter Auto Zeroing 21
Using the LED 21
General Guidelines 21
Symptom Definitions 22
Trouble-shooting 22
Trouble-shooting the RFT 9729 23
Wiring 23
Internal Test Points 23
Customer Service 24
1
1
1
1
1
2
2
2
2
3
Appendix I
Appendix II
Appendix III
Exploded Drawing of the RFT9729 25
RFT9729 Configuration Record 26
Model 268 SMART FAMILY@ Interface Flow Diagram 28
The Remote Flow lrransmitter
1.1 General Description
1.2 Theory of Operation
The Micro Motion@ Remote Flow Transmitter (RFT9729) is a microprocessor-based
mass flow transmitter. The transmitter, in conjunction with a Micro Motion flow sensor,
forms a complete mass flowmeter system.
The transmitter converts the low-Ievel signals from the sensor to 4-20 mA and frequency
outputs. The 4-20 mA signal can be configured to transmit a flow rate, temperature, or
density signal. The frequency output is always a flow rate signal. The transmitter also pro-
duces digital signals for flow rate, flow total, density, and temperature that can be read by
a Rosemount@ Model 268 SMART FAMILY Interface or a HART-compatible controlsystern. Optionally, RS-485 can be selected as a digital communications medium.
Circuitry in the transmitter compensates for individual flow sensor characteristics,
allowing interchange with any Micro Motion Model D flow sensor.
The RFf9729 interfaces with Model D Mass Flowmeters. The input circuit measures the
signals from the left and right velocity detectors on the sensor tube(s). The input data is
digitally filtered to reduce noise and increase the measurement resolution. This input data
is then converted into flow rate data using the flow calibration factor and the sensed
temperature.
The drive circuit generates an oscillatory voltage to vibrate the tubes. The frequency of
oscillation is at the natural frequency of the sensor, and therefore, a process fluid density
measurement can be calculated from the measured natural frequency of the sensor.
A temperature amplifier converts the resistance of the sensor-mounted platinum RTD to a
linearized voltage (i.e., 5 mV per OC) for digitization, temperature compensation of the
sensor, and the Density Monitoring System (DMS) output. The temperature compensation has a resolution of 0.1°C and a range of -240° to 450°C (-400° to 842°F).
The transmitter can be easily used with another Micro Motion sensor simply by entering
the correct calibration data.
1.2.1 Communication
1.2.2 Fault Detection and
Diagnostics
The transmitter is programmed to communicate with other digital equipment using the
HART protocol. For more information on transmitter protocol, please refer to the Remote
Flow Transmitter Digital Communications Instruction Manual, July, 1989, PIN 1002798.
Device interconnection is accomplished by using the transmitter mA output terminals.
As an alternative, an RS-485 interface is also available through jumper configuration on
the processor board and is compatible with the transmitter protocol.
The SMART FAMILY Interface (268) allows direct digital configuration and access to
diagnostics of the transmitter. The 268 connects to the transmitter via the 4-20 mA
current output loop and communicates with the transmitter at the transmitter site, from the
control room, or from any other wiring termination point in the loop. The 268 is generic
and can be used with any RFT9729 transmitter. The same 268 can also be used with any
Rosemount SMART FAMILY transmitter. For more information on the 268, see the
instruction manual entitled Using the SMART FAMILY Interface 268 with the Micro
Motion Remote Flow Transmitter, Section 1.
The digital communications protocol is designed to assist in fault detection and
diagnostics. Fault detection is designed to ensure the functional integrity of the meter and
electronics including the velocity transducers, drive coil, and RTD. During start-up, the
RFT9729 microprocessor checks its RAM and EPROM. A watchdog timer monitors the
operation of the microprocessor to ensure recovery from software malfunctions.
Detected faults, which could cause an error exceeding the accuracy specification, can be
displayed on the 268. Within the RFT9729 itself, if a fault is detected that may indicate
malfunc.'tion of the flowmeter, the mA and frequency outputs are set to an upscale or
downscale level (see Section 3.1, Jumper Configuration on the Processor Board) as an
indication that a failure has occurred. Also, the LED on the front panel flashes on at 4 Hz if
a fault condition occurs. The LED flashes on at 1 Hz during normal operation.
1.2.3 Meter Zeroing
1.3 Independent Exchange of
Flow Sensors and
Transmitters
1.4 Modular Electronics
1.5 Display
Zero flow adjustment (i.e., sensor offset adjustment) is accomplished with the Set Zero
Flow key switch on the front panel, an externally wired set zero switch, or with the
communications protocol auto zero command. During zero flow adjustment, the LED on
the front panel remains on indicating that a zero flow calibration is in progress. The
transmitter will not allow an excessive sensor offset during meter zeroing, protecting
against zeroing while excessive fluid flow exists. See Section 3.3, Transmitter Auto
Zeroing.
Transmitters and flow sensors may be replaced separately since each sensor is
calibrated at the factory and marked with flow calibration and density calibration factors.
Sensors and transmitters calibrated at the factory have matching serial numbers on their
respective nameplates. To match different transmitters and flow sensors, the calibration
factors are simply entered into the transmitter using the communications protocol. No additional calibration or equipment is necessary. For sensors manufactured before calibration factors were put on each unit, contact Micro Motion at 1-800/522-MASS (522-6277)
in Boulder, Colorado for the U.S., or 31-08385-63911 in Veenendaal, the Netherlands, for
Europe. Also, your local service/sales office can assist you.
The electronics in the transmitter can be removed from the housing and replaced
separately, This is facilitated by modular construction and plug-in cable connectors (See
Appendix I, Exploded Drawing). Interchangeability allows one electronics module to
serve as a spare for many transmitters.
A 4 line, 20 character display is incorporated in the RFT9729 front panel. This display
shows the following information:
Flowrate (*)
Density (*)
Temperature (*:
Totalizer
(*) denotes which process variable is the mA output (one only).
2
1.5.1 Totalizer Reset Button
The totalizer reset button has 2 functions. If the button is depressed and kept in position,
the totalizer value is stopped. When released the totalizer value is reset to zero.
Table 1 Specifications
Functional Specifications
Flow Sensor Compatibility
Compatible with all Model D sensors with either 7 -wire or 9-wire feedthroughs and 3-wire
platinum RTD (temperature sensor).
Compatible with all Model DL sensors with either 7-wire or 9-wire feedthrough or Camloc
connector and 3-wire platinum RTD.
Compatible with all Model D sensors with 2-wire copper RTD when rewired as 3-wire at
sensor cable interconnection. Temperature and density measurement accuracy will be
somewhat degraded.
Rangeability
Flow: Minimum span equal to 4.0 microsec. of time difference between velocity sensor
signals. Maximum span equal to 240.0 microsec. of time difference between velocity
sensor signals. Range limits from -120.0 microsec. to +120 microsec. time difference
between velocity signals. Zero may be suppressed or elevated. The 50:1 electronics
rangeability encompasses the range limits of the flow sensor. See sensor specifications
for min. and max. spans of individual sensors.
Density: Minimum span of 0.1 g/cc.
Maximum span of 5.0 g/cc.
Range limits from 0.0 to 5.0 g/cc
Temperature: Lower limit of -240°C (-400°F)
Upper limit of 450°C (840°F)
Minimum span of 20°C
Maximum span of 690°C
Power Supply
Standard: 12 to 30 VDC, 6.5 watts typical, 14 watts maximum. 1 amp minimum start-up
current. Fuse rating: 2 amp. Fuse located on back panel.
Optional: 115 VAG :t25%, 48 to 62 Hz, 9 watts typical, 14 watts maximum or 230 VAG
:t25%, 48 to 62 Hz, 9 watts typical, 14 watts maximum. Fuse rating: 0.25 amp. Fuse
located on back panel.
Humidity Limits
Meets SAMA PMC 31.3, Section 5.2
Ambient Temperature Limits
Operating
0 to 50°C (32 to 122°F)
Storage
-20 to 70°C (-4 to 158°F)
3
Output Signals
* 4 to 20 mA, internally powered, galvanically isolated to :t50 VDC, 0 to 1000 ohm load.
The mA output can represent flow rate, temperature, or density (user-configurable). Maxi-
mum ripple of 1.5% of span at greater than 20 kHz.
* 0 to 15 volt frequency representing flow rate, 2.2k ohm pull-up, galvanically isolated to
:t50 VDC. Sinking capability 0.10 amps in the .'on" condition (0 V level), 30 VDC compliance with the internal pull-up removed in the '.off" condition. Maximum "on" pulse width
of 6, 12, or 24 milliseconds, depending on configuration.
* Bell 202 digital communications signal superimposed on 4-20 mA signal, available for
host control system interface. Frequency 1.2 and 2.2 kHz, amplitude 1.0 to 2.0 mA peak-
to-peak, baud rate 1200 bits-per-second. Load resistance between 250 and 1000 ohms
required. HART protocol compatible.
Optional: RS-485 digital communication signal referenced ~o sensor ground. Amplitude
:t5 V square wave, baud rate 1200 bits-per-second. HARr protocol compatible.
* 0 to 15 volt flow direction, 2.2k ohm pull-up, referenced to frequency output return line.
Sinking capability 0.10 amps in the "on" condition (reverse flow) 30 VDC compliance
with the internal pull-up removed in the "off" condition (forward flow).
* 2.5 VAG at sensor natural frequency, referenced to sensor ground, 10k ohm output
impedance. Used for interface to Micro Motion Density Monitoring System.
* 5 mVrC sensor temperature, referenced to sensor ground, 10k ohm output
impedance. Used for interface to Micro Motion Density Monitoring System.
ScaJeabJe mA Output Adjustment
Engineering units and range points user-selectable between rangeability limits for either
flow rate, temperature, or density.
Scaleable Frequency Output Adjustment
* Frequency set point scaleable from 1 to 10,000 Hz in 1 Hz increments.
* Flow rate set-point scaleable from minimum span to upper range limit. Zero flow rate
always equals zero Hz, frequency linear to flow rate.
Frequency output replaced by 2ND mA output
The secondary milliamp output replaces the frequency output. This has consequences for the
hardware as well as the software.
Hardware
The connection terminal points for the secondary milliamp output are:
Software. (Programming)
Standardwise both mA-outputs will be adjusted to meet in our factory the desired range unless
otherwise specified.
In case the secondary mA-output must be (re)adjusted one will have to do this through the frequency function key with a SFI268 interface.
The 10.000 Hz point corresponds with the 20 mA output.
For example: -desired range 0-500 kg/h
-48-pin connector (24b) 4-20mA(28b) 4-20mA+
-secondary mA-output 4-20 mA over the above mentioned rate.
Frequency must be programmed to be 10.000 Hz at 500 kg/h. Automatically
the 20 mA will correspond with 500 kg/h.
4
Slug Flow Inhibit
Transmitter senses density outside of user-selectable density limits and drives the flow
outputs to indicate zero flow.
Scaleable Low Flow Cutoff
Engineering units and low-ftow cutoff value user-selectable. Below selected value, digital,
milliamp and frequency outputs are driven to zero.
Damping
User-selectable: 0.2, 0.4, 0.8, 1.6, 3.2, 6.4, or 12.8 seconds time constant.
Over Range Capability
* Milliamp output 2 mA (-12.5% of span) to 22 mA (+112.5% of span)
* Frequency output 11 ,520 Hz
Diagnostics
User-selectable downscale (2 mA and a Hz) or upscale (22 mA and 11520 Hz) when
failure of auto zero, sensor, temperature sensor, or electronics is detected.
Output Testing
* Current source:
Transmitter may be commanded to supply a specified current between 2 and 22 mA.
* Frequency source:
Transmitter may be commanded to supply a specified frequency between 1 and 10,000
Hz.
Turn-On Time
Less than 10 seconds
Warm-Up Time
Transmitter reaches stable operation in less than 30 minutes.
Sensor Compensation
Sensors are flow and density calibrated and assigned calibration factors at the factory.
The calibration factors are entered into the transmitter enabling interchangeability of sensors within 0.1% of reading on flow accuracy, 0.001 g/cc on density accuracy and 0.5°C
:to.25% of reading in °C on temperature accuracy.
Hazardous Location Certification
CENELEC
[EEx ib] lIB* or [EEx ib] IIC*
* with approved sensor
5
Performance Specifications
(Reference operating conditions unless otherwise specified. Definitions per AN81/18A
851.1 -1979 unless otherwise specified.)
Accuracy (sensor included):
(includes effects of linearity, hysteresis, and repeatability)
Flow: :to.2010 of rate :to.O1010 of sensor upp~r range limit.
Density: .:to.001 g/cc; DL 100, DL200, D300, and D600
:to.002 g/cc; D65, D100 and D150
:to.004 g/cc; D40, D25, D12, ~nd D6
Temperature: :t1 °G :to.5% of reading expr~ssed in "G
Repeatability (sensor included):
Flow: :!=0.05% of rate :!=0.005% of sensor upper range limit
Density:
:to.OOO5 g/cc; OL 100, OL200, 0300, and 0600
:to.OO10 g/cc; 065, 0100 and 0150
:to.OO2 a g/cc; 040, 025, 01 ~, and 06
Temperature:
Ambient Temperature Effect (transmitter on/~)
Flow: Zero effect :to.OO2% of sensor upper range limit tC.
Span effect :to.OO2% of span tC.
Density:
:to.2°C
:to.00005 g/cc/"F; OL 100, OL200, 0300, and 0600
:to.0001 g/ccrF; 065, 0100 and 0150
:to.0002 g/ccrF; 040, 025, 012, and 06
Temperature:
RFI Effect (sensor excluded)
Analog :to.O1 "Ct'C
Digital :to.10''Ct'C
Level 1, :to.8% of span at 1 Vim per IEC 8d1.3 -1984
Level 2, :t4.00% of span at 3 Vim per IEC 801.3 -1984
Class 3, A, B, C, :to.8% of span at 1 Vim pftr SAMA PMC 33.1
Class 1, A, B, C, :t4.00% of span at 3 Vim per SAMA PMC 33.1
Class 2, A, B, C, :t15% of span at 10 Vim per SAMA PMC 33.1
Conductive conduit for sensor cable, which is earth grounded at both ends, is required
for RFI protection within this specification.
Vibration Effect (transmitter only)
Meets SAMA PMC 31.1, Level
6
Supply Voltage Effect (sensor included)
Physical Specifications
Meets supply voltage effect requirements of SAMA PMC 31
section 5.10.1 through
5.10.5
Electronics Housing
Half 19" cassette. 42TEx 3HE; gray PVC-coated panels
Dimensions: 213 W by 128 H by 235 mm D (8.4 W by 5 H by 9.3 in D)
Weight: 2,6 kg (5.7 Ib)
Electrical Connections
Din 41612 Type F 48 pole connector for sensor and output signals. Separate main
supply connector is available.
Cable from Sensor to Transmitter
3 individually shielded twisted pairs, ,minimum 20 AWG, for 7 wire sensors. Less than 30
pF-per-foot interwire capacitance u~ to 500 ft (150 meters) total cable length.
4 individually shielded twisted pairs,: minimum 22 AWG, minimum 18 AWG for drive pair
for 9 wire sensors. Less than 30 pF-li>er-foot interwire capacitance up to 1000 ft (300 meters) total cable length.
7
Loading...