Sierra 730 User Manual

Sierra Series 730 Accu-Mass

Mass Flow Meters

Instruction Manual

Part Number IM-73-AM

Revision E 05/04

™

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]

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 1994
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
Accu-Mass™ is a trademark of Sierra Instruments, Inc. Other product and company
names listed in this manual are trademarks or trade names of their respective manufac­turers.

Revision D: added NEMA 4 enclosure wiring instructions, updated content and format.

Series 730 Instruction Manual

Table of Contents

Series 730 Mass Flow Meters...........................................................3

Safety Information..........................................................................4

Receipt of Components...................................................................4

Technical Assistance.......................................................................4

Installation Overview......................................................................5

Unobstructed Flow Requirements...............................................5

Installation......................................................................................6

Wiring Connections - NEMA 2 Enclosures......................................7

Wiring Connections - NEMA 4 Enclosures......................................7

Output Signal Wiring.......................................................................8

Troubleshooting the Flow Meter......................................................8

Returning Equipment to the Factory..............................................10

Product Specifications...................................................................11

Figures

1. Series 730 Sensor Assembly......................................................3

2. Recommended Pipe Length Requirements................................6

3. NEMA 2 Wiring Connections..................................................7

4. NEMA 4 Wiring Connections..................................................7

IM-73-E 1

Warnings and Cautions

Warning! All wiring procedures must be performed with the power Off.

Caution! All flow meter connections and fittings must have the same or higher pres-

sure rating as the main pipeline.

Caution! Do not connect power to the 4-20 mA terminals.
Caution! Before attempting any flow meter repair, verify that the line is de-pressurized.
Caution!

Always remove main power before disassembling any part of the flow meter.
Caution! Printed circuit boards are sensitive to electrostatic discharge. To avoid dam-

aging the board, follow these precautions to minimize the risk of damage:

Series 730 Instruction Manual

• 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

2 IM-73-E

Series 730 Instruction Manual

Series 730 Mass Flow Meters

Sierra’s Series 730 Accu-Mass™ Flow Meters provide outstanding
measurement accuracy and fast 200 millisecond response time. The
meters monitor the mass flow rate of air and process gases in ranges
from 0 to 250 scfm. They are available in pipe sizes from 1/4-inch to
3 inches. Accu-mass meters are ideal for monitoring flows of non­corrosive gases compatible with the device’s wetted materials and ap­plications requiring fast time response.

Sierra’s Accu-Mass sensor is a reference-grade platinum resistance
temperature detector (RTD) encapsulated in glass. The platinum RTD
wire is wound on a rugged ceramic mandrel for strength and stability.
The sensor is located at the tip of a 304 stainless steel probe which is
inserted in the gas stream. 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 transducer electronics heats the velocity sensor
to a constant temperature differential above the gas temperature. The
cooling effect of the air as it passes over the heated sensor is meas­ured by the bridge voltage. The meter electronics converts this volt­age into a linear 0-5 VDC, 0-10 VDC, or 4-20 mA output signal.

The meter electronics are packaged in an anodized aluminum NEMA
2 or a painted cast aluminum NEMA 4 enclosure. The electronics are
mounted either directly on the sensing probe or for NEMA 2 enclo­sures, remotely up to 100 feet (60 meters) away.

Accu-Mass™ Sensor

Heat

Gas temperature sensor

Heated velocity sensor

Mass flow

Figure 1. Series 730 Accu-Mass Sensor Probe

IM-73-E 3

Safety Information

We use caution and warning statements in this book to draw your at­tention to important information.

Series 730 Instruction Manual

Warning!

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.

Receipt of Components

When receiving a Sierra mass flow meter, carefully check the outside
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 first contacting Sierra Customer Service.

Technical Assistance

If you encounter a problem with the flow meter, review the configura­tion information for each step of the installation procedure. Verify
that the flow conditions are consistent with factory recommenda­tions. Refer to Troubleshooting for specific information and recom­mendations.

If the problem persists after following the troubleshooting procedures
outlined in this manual, contact Sierra Instruments by fax or by E­mail ([e-mail]); or, visit the Sierra website at
www.sierrainstruments.com for further assistance. 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 +31
20 6145810. When contacting Technical Support, make sure to in­clude this information:

Caution!

This statement appears with information that
is important for protecting your equipment
and performance. Read and follow all cau­tions that apply to your application.

• the flow range, serial number, Sierra order number and model
number (all marked on the meter nameplate)

• the problem you are encountering and any corrective action taken

• application information (gas, pressure, temperature and piping

configuration)

4 IM-73-E

Series 730 Instruction Manual

Installation Overview

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 ambient temperature falls within the limits of: 32°F (0°C)
to 120°F (50°C).

3. The location meets the required minimum number of pipe di­ameters upstream and downstream of the sensor head (see Fig­ure 2).

4. 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.

5. For remote installations, verify the supplied cable length is
sufficient 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 tem-

perature

Unobstructed Flow Requirements

Select an installation site that will minimize possible distortion in the
flow profile. Valves, elbows, control valves and other piping compo­nents may cause flow disturbances. 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 given in Figure 2.

IM-73-E 5

Series 730 Instruction Manual

10 D 5 D

Flow

One 90° elbow before meter

Flow meter

10 D 5 D

Flow

Reduction before meter

Flow meter

15 D 5 D

20 D 5 D

Flow

Two 90° elbows before
meter in one plane

Flow meter

Flow

Expansion before meter

Flow meter

25 D 10 D

25 D 10 D

Flow

Two 90° elbows before meter out
of plane (if three 90° bends present,
double recommended length)

Flow meter

Flow

Regulator or valve partially closed before meter
(If valve is always wide open, base length
requirements on fitting directly preceding it)

Flow meter

D = number of diameters of straight pipe required between the disturbance and
the flow meter (upstream); and, number of diameters of straight pipe required
downstream of the flow meter

Caution!

All flow meter connections

and fittings must have the

same or higher pressure

rating as the main pipeline.

Figure 2. Recommended Pipe Length Requirements for Installation

Installation

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 piping requirements.

3. Position the meter with the flow direction arrow pointing down­stream in the direction of flow.

4. Tighten fittings until leak tight (refer to published standards for
specific recommendation).

5. Check the system’s entire flow path thoroughly for leaks.

6 IM-73-E

Series 730 Instruction Manual

Wiring Connections - NEMA 2 CE Enclosures

Warning!

All wiring procedures

must be performed

with the power Off.

NEMA 2 enclosures are supplied with a 6-pin connector for direct
connection to the supplied mating connector. The pin designations
are given in Figure 3 below. Connect 15 VDC input power (300 mA
load, maximum) to pin 1 and power ground to pin 5. See “Output Sig­nal Wiring” for signal wiring instructions.

•Female Cable Socket Mating Connector (Female Solder Side View)

1 Positive power lead (Red)

1

5

2 Output signal (Wht)
3 Signal common (Blk)

6

2

4

3

Figure 3. NEMA 2 CE Enclosure Wiring Connections

4 Bridge voltage (Org Not Required)
5 Power return (Grn)
6 Shield (Not Required)

IM-73-D 7

Caution!

Do not connect power to

the 4-20 mA terminals.

Series 730 Instruction Manual

Output Signal Wiring

All flow meters are equipped with either a calibrated 0–5 VDC, 0–10
VDC or 4–20 mA output signal. These linear output signals represent
0 to 100% of the flow meter user full scale.

DC Output Wiring

The 0-5 VDC or 0-10 VDC output signal can drive a minimum load of
1000 Ohms. For 0-5 VDC or 0-10 VDC connections, connect to the
terminals marked Output signal and Signal ground.

4–20 mA Output Wiring

The 4-20 mA current loop output is self-powered (non-isolated).
The maximum loop resistance (load) for the output is 400 Ohms. For
a 4–20 mA connection, connect to the terminals marked Output sig­nal and Signal ground.

Troubleshooting the Flow Meter

Begin hardware troubleshooting by verifying the following facilities is­sues are correct. These areas impact system operation and must be
corrected prior to performing any flow meter inspections.

Caution!

Before attempting any flow

meter repair, verify that the

line is not pressurized.

Caution!

Always remove main power

before disassembling any

part of the mass flow meter.

1. Verify the incoming power to the flow meter is present and of the
correct voltage and polarity.

2. Check the flow meter wiring for correct connections.

3. Verify the flow meter is installed with the correct number of up­stream and downstream pipe diameters as shown in Figure 2.

4. Verify the flow direction indicator is correctly aligned pointing
downstream of flow.

5. Make sure there are no leaks in the line being measured.

After verifying the factors above, follow the troubleshooting procedures
outlined on the next page. If you need to return the flow meter to the
factory, see page 10 for return shipping instructions.

Flow Meter Calibration

Sierra Instruments maintains a fully-equipped calibration laboratory.
All measuring and test equipment used in the calibration of Sierra me­ters are traceable to NIST standards. Sierra is ISO-9001 registered and
conforms to the requirements of ANSI/NCSL-Z540 and ISO/IEC
Guide 25. If the flow body or electronics have been damaged or you
simply want to have the flow meter re-calibrated, contact the factory
for return shipping instructions. Calibration must be performed by
qualified personnel using NIST-traceable equipment.

8 IM-73-E

Series 730 Instruction Manual

Problem Possible Cause Solution

Flow measurement is
erratic or fluctuating

Velocity measurement
seems too high or low

No response to flow from
sensor assembly

Very erratic or non-uniform flow Follow installation requirements

shown in Figure 2

Flow meter installed with less than re­quired minimum pipe diameters up­stream and downstream of the sensor

Probe is not secured to a solid base Secure probe to a non-vibrating solid

Sensor component broken Return to factory for replacement
Malfunction in system

electronics
Moisture present in gas flow Install a water trap or filter upstream

Sensor assembly not aligned correctly
to flow

No power Turn on power to the flow meter

Flow profile distortions Try to find another location for the

Follow installation requirements
shown in Figure 2

mount

Return to factory for evaluation

of the flow sensor
Correct alignment with the flow indica-

tor pointing downstream in the direc­tion of flow

meter

Extremely turbulent flow Do not place the meter near a ventila-

tor, static mixer or valve
Sensor failure Return to factory for repair
Malfunction in system

electronics

System will not zero Out of calibration Return to factory for calibration

Probe tip is broken Return to factory for repair

4-20 mA output circuit not
indicating 4 mA at zero
flow

Output pegs plus or minus Flow body not plugged in Plug in both connectors

Improper current loop resistance; total
current loop resistance must be no
less than 150 Ohms and no greater
than 450 Ohms

Malfunction in system
electronics

Return to factory for evaluation

Install load resistor or use larger

gauge wire

Return to factory for evaluation

IM-73-E 9

Returning Equipment to Factory

Before returning any mass flow meter to the factory, you must com­plete a Sierra Calibration/Repair Data Sheet. You may download the
data sheet to your computer by visiting the Sierra website at
www.sierrainstruments.com. Or, contact Customer Service at:

[e-mail] (Email) or,
[phone] or [phone] in the US,
or [phone] in Europe.

Return shipments to:

USA Headquarters
Sierra Instruments Service Department
5 Harris Court, Building W
Monterey, CA 93940

European Headquarters
Sierra Instruments b.v. Service Department
Bolstoen 30A
1046 AV Amsterdam, The Netherlands

Series 730 Instruction Manual

When returning a component, make sure to include the completed
Calibration/Repair Data Sheet with the shipment.

10 IM-73-E

Series 730 Instruction Manual

Product Specifications

Operating Specifications

Gases Most non-combustible, non-corrosive gases
Mass Flow Rates

Mass Flow Rate for Air

NPT Size Minimum Range Maximum Range

1/4-inch 0–0.035 scfm 0–4.5 scfm
1/2-inch 0–0.5 scfm 0–12 scfm
3/4-inch 0–1 scfm 0–25 scfm

1 1/4-inch 0–2 scfm 0–50 scfm

2-inch 0–5 scfm 0–125 scfm
3-inch 0–10 scfm 0–250 scfm

(1) Contact factory for ranges of other gases

(1)

Gas Pressure 150 psig (10 barg)*

Pressure Drop Negligible

Gas & Ambient Temperature Gas.............................14° to 176°F (–10° to 80°C)

Leak Integrity 1 X 10-2 atm cc/sec of helium maximum
Power Requirements 15 or 24 VDC, 300 mA
Output Signal Linear 0-5 VDC or 0-10 VDC proportional to mass flow rate, 1000 Ohms

*Maximum gas pressure is determined by the mechanical process connections, as well as, the ap­plication conditions. Mechanical limitations are shown above, please consult factory for application
limitations.

Ambient......................32° to 120°F (0° to 50°C)

minimum load resistance; or, linear 4-20 mA proportional to mass flow rate,
400 Ohms maximum resistance

Performance Specifications

Accuracy ± 1% of full scale + 0.5% of reading over 32 to 120°F (0 to 50°C) and 5 to 30

Repeatability ± 0.2% of full scale
Temperature Coefficient ± 0.02% of reading per °F within ± 50°F of customer specified conditions

Pressure Coefficient Negligible within ±50 psig (3.4 barg) of customer specified conditions

Response Time 200 milliseconds to 63% of final velocity value

psia (0.3 to 2 barg)

± 0.03% of reading per °F within ± 50°F to 100°F of customer specified conditions
±0.04% of reading per °C within ± 25°C of customer specified conditions
±0.06% of reading per °C within ± 25°C to 50°C of customer specified conditions

(Special calibration required for higher pressures)

Physical Specifications

Wetted Materials Anodized aluminum or 316 stainless steel flow body

Enclosure Anodized aluminum NEMA 2

Glass-coated sensor; epoxy; Viton O-rings

Painted cast aluminum NEMA 4

IM-73-E 11

730/600 WIRING CONNECTIONS

No#. Color Signal
1 Black Sig. Ground
2 White Signal
3 Red DC input Power
4 N/C
5 N/C
6 Green Power Ground
7 (Brown or Orange) (Bridge)

Blue Hi Rose Connector

1

2

3

6

7

5

4

Female Mating Connector
Solder Side

No#. Color Signal
1 Black Sig. Ground
2 White Signal
3 Red DC input Power
4 N/C
5 N/C
6 Green Power Ground
7 (Brown or Orange) (Bridge)

No#. Color Signal
1 Red DC input Power
2 White Signal
3 Black Sig. Ground
4 (Brown or Orange) ( B r i dg e)
5 Green Power Ground
6

1

2

3

4

5

+VDC Input
Power Ground
Output Signal
Signal Ground

7

6

Black Connector
Female Mating Connector
Solder Side

5

4

3

Silver Connector

2

Female Mating Connector

6

Solder Side

1

E7
Enclosure

Red

Green

White

Black

N/C

To Sensor