Sierra Fast-Flo 620S Series User manual

Series 620S Instruction Manual Table of Contents
IM-62S-B 0-1
Sierra Series 620S Fast-Flo™
Insertion Mass Flow Meter
Instruction Manual
Part Number IM-62S
01/99 Revision B
5 Harris Court, Building L Monterey, CA 93940
[phone] [phone] Fax [phone]
http://www.sierrainstruments.com
Sierra Instruments b.v. Bolstoen 30A 1046 AV Amsterdam The Netherlands
[phone] Fax [phone]

Table of Contents Series 620S Instruction Manual
0-2 IM-62S-B
Customer Notice
Sierra Instruments, Inc. is not liable for any damage or personal injury, whatsoever,
resulting from the use of Sierra Instruments standard mass flow meters for oxygen
gas. You are responsible for determining if this mass flow meter is appropriate for
your oxygen application. You are responsible for cleaning the mass flow meter to
the degree required for your oxygen flow application.
© COPYRIGHT SIERRA INSTRUMENTS 1998
No part of this publication may be copied or distributed, transmitted, transcribed, stored in
a retrieval system, or translated into any human or computer language, in any form or by
any means, electronic, mechanical, manual, or otherwise, or disclosed to third parties
without the express written permission of Sierra Instruments. The information contained in
this manual is subject to change without notice.
TRADEMARKS
Fast-Flo™ and Smart Interface™ software are trademarks of Sierra Instruments, Inc.
Other product and company names listed in this manual are trademarks or trade names of
their respective manufacturers.
All Sierra products are Year 2000 compliant.

Series 620S Instruction Manual Table of Contents
IM-62S-B 0-3
Table of Contents
Chapter 1 Introduction
Series 620S Mass Flow Meters......................................1-1
Using this Manual.................................................1-1
Note and Safety Information.....................................1-2
Receipt of System Components .................................1-2
Technical Assistance..............................................1-2
The Series 620S Flow Sensing Principle...........................1-3
Smart Electronics Features............................................1-4
Enclosure Options .....................................................1-5
Smart Interface Software..............................................1-5
Chapter 2 Installation and Wiring
Installation Overview..................................................2-1
Site Selection.......................................................2-1
Unobstructed Flow Requirements...............................2-2
Installation..............................................................2-3
Wiring Connections ...................................................2-4
Input Power Wiring...............................................2-4
Output Signal Wiring .............................................2-5
Alarm Output Wiring..............................................2-7
Remote Sensor Probe Wiring....................................2-8
Range Selection Wiring...........................................2-9
Chapter 3 Operating Instructions
Using the Smart Electronics Basic Features........................3-1
Using the Single-Digit LED for Programming.................3-2
Using the LCD Display for Programming......................3-3
Entering Alarm Parameters.......................................3-4
K-factor Adjustment ..............................................3-5
User Full Scale Adjustment......................................3-6
Time Response Delay Adjustment...............................3-7
Totalizer Reset.....................................................3-7
Using the Smart Electronics Advanced Features...................3-9
Voltage Zero Adjustment.........................................3-9
Voltage Span Adjustment.........................................3-9
Current Zero Adjustment........................................3-10
Current Span Adjustment........................................3-10
Instrument Validation.................................................3-11
Electronics Validation Procedure...............................3-12
Sensor Validation Procedure....................................3-13

Table of Contents Series 620S Instruction Manual
0-4 IM-62S-B
Chapter 4 Troubleshooting and Repair
Troubleshooting the Flow Meter.....................................4-1
Obtaining a Return Material Authorization..........................4-3
Appendix A Product Specifications
List of Figures
1-1. Series 620S Sensor Assembly ..............................1-3
2-1. Recommended Pipe Length Requirements.................2-2
2-2. Wiring Access.................................................2-4
2-3. Input Power Connections....................................2-4
2-4. Output Signal Wiring.........................................2-5
2-5. Load Resistance Versus Input Voltage.....................2-6
2-6. Isolated 4-20 mA Current Loop Connections .............2-6
2-7. Non-isolated 4-20 mA Current Loop Connections .......2-6
2-8. Isolated Alarm Output Connections.........................2-7
2-9. Non-isolated Alarm Output Connections...................2-7
2-10. Remote Electronics to Sensor Connections................2-8
2-11. Sensor J Box to Remote Enclosure Connections .........2-8
2-12. Range Selection Wiring......................................2-9
3-1. Display/Keypad Commands.................................3-1
3-2. Electronics Validation Component Locations.............3-11
3-3. Sensor Validation Component Locations .................3-13
List of Tables
3-1. Electronics Validation Results..............................3-13
3-2. Sensor Validation Results...................................3-14

Series 620S Instruction Manual Table of Contents
IM-62S-B 0-5
Warnings and Cautions
Warning! All wiring procedures must be performed with the power Off.
Warning! To avoid potential electric shock, follow National Electric Code safety practices
or your local regulations when wiring this unit to a power source and to peripheral devices.
Failure to do so could result in injury or death.
Warning! Do not power the flow meter with the sensor jumper wires disconnected. This
could cause over-heating of the sensors and/or damage to the electronics.
Warning! Always remove main power before disassembling any part of the mass flow meter.
Caution! Before making adjustments to the Smart electronics device, verify the flow meter
is not actively monitoring or reporting to any master control system. Adjustments to the
electronics will cause direct changes to flow control settings.
Caution! All flow meter connections and fittings for pipe tapping must have the same
or higher pressure rating as the main pipeline.
Caution! To avoid serious injury, DO NOT loosen a compression fitting under pressure.
Catuion! Before attempting any flow meter repair, verify that the line is de-pressurized.
Caution! Printed circuit boards are sensitive to electrostatic discharge. To avoid
damaging the board, follow these precautions to minimize the risk of damage:
• before handling the assembly, discharge your body by touching a grounded,
metal object
• handle all cards by their edges unless otherwise required
• when possible, use grounded electrostatic discharge wrist straps when handling
sensitive components

Table of Contents Series 620S Instruction Manual
0-6 IM-62S-B

Series 620S Instruction Manual Chapter 1 Introduction
IM-62S-B 1-1
Chapter 1 Introduction
Series 620S Fast-Flo™ Mass Flow Meters
Sierra’s Series 620S Smart Mass Flow Meter provides a reliable
solution for inert gas flow measurement applications. Low-flow
sensitivity, fast response and outstanding rangeability have made
this model the instrument of choice for many critical gas flow
applications.
The Smart microprocessor-based transmitter integrates the func-
tions of flow-range adjustment, meter validation and diagnostics in
a probe-mounted or remote NEMA 4X (IP65) housing. Mass flow
rate and totalized flow, as well as other configuration variables can
be displayed on the meter’s optional 2 x 12 backlit LCD panel. The
meter provides an optical/galvanic isolated flow output, two alarm
outputs and one contact input for range or gas selection. The pro-
grammable transmitter is easily configured via RS-232 and Sierra’s
Smart Interface software or through three push buttons built into
the device.
Depending on the probe length, the Series 620S is suitable for
pipes or ducts from two inches up to 48 inches (DN50 up to
DN1200). The Series 620S Mass Flow Meter’s simple installa-
tion combines with an easy-to-use interface that provides quick set
up, long term reliability and accurate mass flow measurement over
a wide range of conditions.
Using This Manual
This manual provides the information you need to install and operate
the Series 620S Smart Insertion Mass Flow Meter. The four chap-
ters of this manual cover these areas:
• Chapter 1 includes the introduction and product description
• Chapter 2 provides installation and wiring instructions
• Chapter 3 describes system operation and programming
• Chapter 4 covers troubleshooting and repair
The product specifications and dimensional drawings are found in
Appendix A.

Chapter 1 Introduction Series 620S Instruction Manual
1-2 IM-62S-B
Note and Safety Information
We use note, caution and warning statements throughout this book
to draw your attention to important information.
Warning! Caution! Note
This statement appears with
information that is important to
protect people and equipment
from damage. Pay very close
attention to all warnings that
apply to your application.
This statement appears with
information that is important
for protecting your equipment
and performance. Read and
follow all cautions that apply
to your application.
This statement appears with
a short message to alert you
to an important detail.
Receipt of System Components
When receiving a Sierra mass flow meter, carefully check the out-
side packing carton for damage incurred in shipment. If the carton
is damaged, notify the local carrier and submit a report to the factory
or distributor. Remove the packing slip and check that all ordered
components are present. Make sure any spare parts or accessories
are not discarded with the packing material. Do not return any
equipment to the factory without a Return Material Authorization
(RMA, see Chapter 4).
Technical Assistance
If you encounter a problem with your flow meter, review the con-
figuration information for each step of the installation, operation and
setup procedures. Verify that your settings and adjustments are con-
sistent with factory recommendations. Refer to Chapter 4, Trouble-
shooting, for specific information and recommendations.
If the problem persists after following the troubleshooting proce-
dures outlined in Chapter 4, contact Sierra Instruments by fax or by
E-mail ([email protected]). For phone support you
may call [phone] or [phone] between 8:00 a.m.
and 5:00 p.m. PST. In Europe contact Sierra Instruments b.v. at
[phone]. When contacting Technical Support, make sure to
include this information:
• the flow range, serial number and Sierra order number and
model number (all marked on the meter nameplate)
• if possible, the firmware version (visible at start up on the
meter display)
• the problem you are encountering and any corrective action taken
• application information (gas, pressure, temperature, piping
configuration)

Series 620S Instruction Manual Chapter 1 Introduction
IM-62S-B 1-3
The Series 620S Flow Sensing Principle
Sierra’s unique Fast-Flo™sensor probe is responsible for the unsur-
passed accuracy and reliability of Sierra mass flow meters. The
sensor consists of two sensing elements–a velocity sensor and a
temperature sensor which automatically corrects for changes in gas
temperature. When power is applied to the flow meter, the trans-
ducer electronics heats the velocity sensor to a constant temperature
differential above the gas temperature and measures the cooling ef-
fect of the gas flow. The electrical power required to maintain a
constant temperature differential is directly proportional to the gas
mass flow rate. The meter electronics measure this power and con-
vert it into a linear 0-5 VDC (0-10 VDC optional) and 4-20 mA out-
put signal.
The Fast-Flo sensors are reference-grade platinum resistance tem-
perature detectors (RTD) encapsulated in glass. The platinum RTD
wire is wound on a rugged ceramic mandrel for strength and stabil-
ity. The sensor is located at the tip of a 0.375 inch (3/8”) diameter,
304 stainless steel probe which is inserted in the gas stream. The
Smart electronics are packaged in a weather-proof NEMA 4X (IP65)
enclosure mounted either directly on the sensing probe or remotely
up to 100 feet (60 meters) away.
Gas temperature sensor
Heat
Heated velocity sensor
Fast-Flo™ Sensor
Mass flow
Figure 1-1. Series 620S Sensor Assembly

Chapter 1 Introduction Series 620S Instruction Manual
1-4 IM-62S-B
Smart Electronics Features
Instrument Validation
Two simple tests offer full “field-validation” of your Smart mass
flow meter. The first test checks the system electronics, linearization
and microprocessor functionality. This is performed by injecting a
known input value and confirming that the flow meter outputs the ex-
pected value. The second test verifies that the instrument’s primary
sensing elements have not drifted or shifted from their original cali-
bration. This is accomplished by measuring the resistance of the ve-
locity and temperature sensors and comparing the results to the
NIST-traceable calibration data provided with the flow meter. To-
gether, these tests confirm that your meter is working correctly and
the calibration variables did not drift, shift or change values.
Dual Range or Dual Gas Calibration (Optional)
Select one of two factory calibrated flow ranges using a simple ex-
ternal customer-supplied single contact closure.
User Full Scale Flow Rate
Field-configure from 50% to 100% of the factory full scale setting
(factory full scale is normally set to 125% of the user-specified maxi-
mum flow rate). This adjustment can be made for each flow range.
Alarms
Program high and low or window alarm limits independently for each
flow range. The solid state contacts are isolated with one common.
K-Factor Correction
Change the calibration correction factor to compensate for flow pro-
file disturbances or specific application conditions. The K-factor is a
multiplication factor applied to the linearized flow signal. You may
set the K-factor individually for each flow range.
Dual Output Signals
Smart flow meters offer two separate linear output signals propor-
tional to flow, 0-5 VDC (0-10 VDC optional) and 4-20 mA. The
4-20 mA output can be field-configured as an active loop powered
by the flow meter or an optically isolated passive loop requiring an
external power supply.

Series 620S Instruction Manual Chapter 1 Introduction
IM-62S-B 1-5
Totalizer
With the optional LCD display, actual mass flow appears on line 1
and the totalized flow on line 2 both in the user-specified engineer-
ing units. The totalizer counts only the selected range and when
ranges are switched, the value of the non-selected range is stored in
memory. You may reset the totalizer using the 3 function buttons
mounted on the PCA or by using a hand-held magnet.
Zero and Span Outputs
Validate and adjust the settings to ensure output circuits are correct.
Time Response Delay
Select from a low response for faster tracking to a high response
for a smoother output.
Enclosure Options
Flow meter electronics are available mounted directly to the flow
body, or remotely mounted up to 100 feet (60 meters) away. The
electronics housing may be used indoors or outdoors.
Display options include a 2 x 12 character LCD display of mass flow
rate including totalized mass, or a single-digit LED located on the de-
vice printed circuit board. Local operation and reconfiguration is ac-
complished using the three push buttons operated via finger touch.
Smart electronics include nonvolatile memory that stores all configu-
ration information. The memory allows the flow meter to function
immediately upon power up, or after an interruption in power.
Smart Interface™Software
Sierra’s Smart Interface Windows™-based software is available for
connecting your PC directly to the mass flow meter. An RS-232
serial cable along with floppy disks containing the program and
system files are available from the factory. See the Smart Interface
User Guide included with the software for operating instructions.
(Order code for this package is 620-SIP.)

Chapter 1 Introduction Series 620S Instruction Manual
1-6 IM-62S-B

Series 620S Instruction Manual Chapter 2 Installation
IM-62S-B 2-1
Chapter 2 Installation
Installation Overview
The Series 620S flow meter is factory calibrated to the specific pipe
size shown on the meter’s Certificate of Calibration. The factory
calibration eliminates the task of calculating the average flow across
the pipe to determine the correct insertion depth. Simply insert the
flow meter sensor to the centerline position of the pipe. (If the pipe
size differs from the meter’s calibrated size, return the meter to the
factory for re-calibration.)
When selecting an installation site, make sure that:
1. Line pressure and temperature will not exceed the flow meter
rating. Temperature should not vary more than 120°F (50°C)
from the calibration temperature. Line pressure should not vary
more than 50 psi (3.4 bar) around the calibrated pressure.
2. The location meets the required minimum number of pipe
diameters upstream and downstream of the sensor head (see
Figure 2-1).
3. Safe and convenient access with adequate clearance. Also, verify
the meter is located where the gas is clean and dry and the meter
is calibrated for the gas to be measured.
4. For remote installations, verify the supplied cable length is suffi-
cient to connect the flow meter sensor to the remote electronics.
(Do not extend or shorten the supplied cable between the probe
and the electronics.)
Also, before installation check your flow system for anomalies
such as:
•leaks
•valves or restrictions in the flow path that could create distur-
bances in the flow profile that might cause unexpected flow rate
indications
•heaters that might cause rapid excursions in the measured temperature

Chapter 2 Installation Series 620S Instruction Manual
2-2 IM-62S-B
Unobstructed Flow Requirements
Select an installation site that will minimize possible distortion in the
flow profile. Valves, elbows, control valves and other piping com-
ponents may cause flow disturbances. Check your specific piping
condition against the examples shown below. In order to achieve
accurate and repeatable performance install the flow meter using the
recommended number of straight run pipe diameters upstream and
downstream of the sensor.
Flow meter
A B
Example 1.
One 90° elbow before meter
Flow meter
A B
Example 2.
Two 90° elbows before meter in one plane
Flow meter
A B
Example 3.
Two 90° elbows before meter out of plane (if three
90° bends present, double recommended length)
Flow meter
A B
Example 4.
Reduction before meter
Flow meter
A B
Example 5.
Expansion before meter
Example 6.
Regulator or valve partially closed before meter (If valve is always
wide open, base length requirements on fitting directly preceding it)
Flow meter
A B
Example A Upstream(1) Requirements B Downstream(2) Requirements
110 D 5 D
2 15 D 5 D
3 25 D 10 D
4 10 D 5 D
5 20 D 5 D
6 25 D 10 D
(1) Number of diameters (D) of straight pipe required between upstream disturbance and the flow meter.
(2) Number of diameters (D) of straight pipe required downstream of the flow meter.
Figure 2-1. Recommended Pipe Length Requirements for Installation

Series 620S Instruction Manual Chapter 2 Installation
IM-62S-B 2-3
Installation
Use the following data as a guide to prepare the pipe for flow meter
insertion. Refer to a standard code for all pipe tapping operations.
The following instructions are general in nature and intended for
guideline purposes only.
1. Turn off the flow of process gas. Verify that the line is not
pressurized.
2. Confirm that the installation site meets the minimum upstream
and downstream pipe diameter requirements. See Figure 2-1.
3. Use a cutting torch or sharp cutting tool to tap into the pipe. The
pipe opening must be at least .375 inches in diameter. (Do not
attempt to insert the sensor probe through a smaller hole.)
1. Remove all burrs from the tap. Rough edges may cause flow
profile distortions that could affect flow meter accuracy. Also,
obstructions could damage the sensor assembly when inserting
into the pipe.
1. Mount the 3/8 inch compression fitting on the pipe. Make sure
this connection is within ± 5° perpendicular to the pipe centerline.
1. When installed, cap the fitting. Run a static pressure check on the
connection. If pressure loss or leaks are detected, repair the con-
nection and re-test.
2. Insert the sensor probe through the
compression fitting into the pipe.
The correct insertion depth places
the larger hole in the probe at the
pipe’s centerline. Do not force
into the pipe.
1. Align the sensor head using the flow direction indicator. Adjust
the indicator parallel to the pipe and pointing downstream in the
direction of flow.
1. Tighten the compression fitting to lock the flow meter in posi-
tion. When the compression fitting is tightened, the position is
permanent (unless using Teflon ferrules).
Caution!
All flow meter connections
and fittings must have the
same or higher pressure
rating as the main pipeline.
Flow
direction
indicator
points
downstream
Flow Pipe centerline
Caution!
To avoid serious injury,
DO NOT loosen the
compression fitting
under pressure.

Chapter 2 Installation Series 620S Instruction Manual
2-4 IM-62S-B
Wiring Connections
The NEMA 4X enclosure contains an integral wiring compartment
with one dual strip terminal block for power and signal connections
and one dual strip terminal block for sensor connections. The en-
closure has one 1/2 inch female NPT conduit entry. The terminal
designations are labeled inside the enclosure cover.
Smart electronics
and wiring connections
inside cover
To access components:
1. Loosen 4 screws.
2. Remove cover.
1/2 inch
FNPT
conduit
entry
Figure 2-2. Wiring Access
Input Power Wiring
Depending on the flow meter configuration, connect 11 to 18 VDC
or 18 to 30 VDC (625 mA load, maximum) as shown below. Con-
firm power configuration before applying power. See the flow
meter nameplate for input power rating.
TB2
PWR (+)
PWR (–)
+
–Power & signal
1
2
15
16 Sensor
12
56TB1
Figure 2-3. Input Power Connections
Warning!
All wiring procedures
must be performed
with the power Off.
Warning!
To avoid potential electric
shock, follow National
Electric Code safety prac-
tices or your local code
when wiring this unit to a
power source and to pe-
ripheral devices. Failure to
do so could result in injury
or death.

Series 620S Instruction Manual Chapter 2 Installation
IM-62S-B 2-5
Output Signal Wiring
All flow meters are equipped with either a calibrated 0-5 VDC (0-10
VDC optional) or a calibrated 4-20 mA output signal. These linear
output signals represent 0-100% of the flow meter user full scale.
DC Output Wiring
The 0-5 VDC (0-10 VDC optional) signal can drive a load of 1000
Ohms. The optional 0-10 VDC output signal is not available for
power sources below 15 VDC. Connect as shown below.
V out (+)
V out (–)
1
2
15
16
Figure 2-4. VDC Output Wiring Connections
4-20 mA Output Wiring
The 4-20 mA current loop output can be self-powered by the flow
meter’s power supply (non-isolated) or externally powered (isolated)
requiring a separate 12 to 36 VDC power supply. The maximum
loop resistance (load) for both types of current loop outputs are de-
pendent upon the supply voltage and are given in Figure 2-5.
Rload is the total resistance in the loop, including the wiring resis-
tance. To calculate Rmax, the maximum Rload for the loop, use the
maximum loop current, 20 mA. The voltage drop in the loop due to
resistance is 20 mA times Rload and this drop is subtracted from the
input voltage. Thus:
Rmax the maximum load resistance = 50 *(Vsupply – 7.5V)
To use an external power supply for an isolated 4-20 mA output,
connect as shown in Figure 2-6. For an internally powered non-
isolated 4-20 mA output, connect as shown in Figure 2-7.

Chapter 2 Installation Series 620S Instruction Manual
2-6 IM-62S-B
Figure 2-5. Load Resistance Versus Input Voltage
R load 4-20 out (+)
4-20 out (–)
12 VDC
to
36 VDC
Current
– +
1
2
15
16
Figure 2-6. Isolated 4-20 mA Current Loop Connections
4-20 out (+)
V out (–)
AUX PWR OUT
Jumper
Current
R load
1
2
15
16
(Common)
Figure 2-7. Non-isolated 4-20 mA Current Loop Connections
VsupplyRmax
(Volts) (Ohms)
11 (min) 175
12 225
15 375
18 525
24 825
30 1,125
36 (max) 1,425

Series 620S Instruction Manual Chapter 2 Installation
IM-62S-B 2-7
Alarm Output Wiring
Two alarm outputs (Low Alarm and High Alarm) are included on the
flow meter terminal block. The alarm outputs relays are normally-open
single-pole relays with one common connection.
There are two connection options for alarm outputs–the first with a sepa-
rate power supply (isolated) and the second using the flow meter power
supply (non-isolated). Use a separate power supply if a specific voltage
is needed for the alarm output. Use the second (non-isolated) configura-
tion if the voltage at the flow meter’s power supply is an acceptable
driver voltage for the load connected. (Take into account that the current
used by your alarm loads have to come from the flow meter’s power
supply.) In either case, the voltage of the alarm output is the same as the
voltage supplied to the circuit.
To use an external power supply for an isolated alarm output, con-
nect as shown in Figure 2-8. To use the internally powered, non-
isolated alarm output connect as shown in Figure 2-9. For a win-
dow alarm connect both outputs together.
ALRM RTN
Load Load
LO ALARM (–)
HI ALARM (–)
AC or DC
power supply 1 2
15
16
Figure 2-8. Isolated Alarm Output Connections
ALRM RTN
LoadLoad
LO ALARM (–) HI ALARM (–)
COMMON
AUX DC PWR OUT
1
2
15
16
Figure 2-9. Non-isolated Alarm Output Connections

Chapter 2 Installation Series 620S Instruction Manual
2-8 IM-62S-B
Remote Sensor Probe Wiring
Use only factory supplied cables when connecting the sensor
probe to a remotely mounted flow meter enclosure. The electron-
ics, sensors and interconnecting cables supplied by Sierra Instru-
ments are calibrated as a complete precision mass flow circuit.
To connect the sensor probe to a remotely mounted electronics en-
closure, see Figure 2-10. To make wiring connections from a
sensor probe junction box to a remotely mounted enclosure, see
Figure 2-11.
Velocity
sensor
RED GREEN
ORANGE
WHITE
BLACK
Temperature
sensor
Remote
enclosure Sensor
probe
56
12
Figure 2-10. Remote Electronics Enclosure to Sensor Connections
RED GREEN
ORANGE
WHITE
BLACK
Remote
enclosure
Sensor
probe
junction
box
12
56
Figure 2-11. Sensor Junction Box to Remote Enclosure Connections
Caution!
Changing the length of
cables or interchanging
sensors or sensor wiring
will affect the accuracy of
the flow meter. You can-
not add or subtract wire
length without returning
the meter to the factory
for re-calibration.