Sierra 900 User Manual

Series 240/241 Instruction Manual Table of Contents

Sierra Series 900

Single & Dual Channel System

Instruction Manual

Part Number IM-90-1

07/05 Revision D.1

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]

IM-24-C 0-1

Series 900 Single & Dual Instruction Manual

CUSTOMER CAUTION

RE: OXYGEN SERVICE

Sierra Instruments, Inc., is not liable for any dam­age or personal injury, whatsoever, resulting from
the use of Sierra Instruments mass flow meters or
controllers for oxygen gas. Although Sierra cleans
its mass flow meters and controllers prior to ship­ment, we make no claim or warranty that their
cleanliness renders them safe for oxygen service.
The customer must clean Sierra Instruments mass
flow meters or controllers to the degree required
for the customer’s oxygen flow applications.

© 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
Side-TrakTM and Flo-BoxTM are trademarks of Sierra Instruments Inc.

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Series 900 Single & Dual Instruction Manual

1. Introduction ............................................................................. 1

2. Locating System Electronics .................................................. 2

3. Front Panel Functions ............................................................ 3

3.1 Channel Selection .............................................................. 3

3.2 Reading Flow Value .......................................................... 3

3.3 Flow Setpoint Display and Adjustment ................................ 3

3.4 High/Low Alarm Display and Adjustment ........................... 3

3.5 Totalize (Mass Flow Integration) Function ........................... 4

3.5 3.5.1 Reset Totalize Function ........................................... 4

4. Rear Panel Connections ........................................................ 5

4.1 Power Line and Fuse .......................................................... 5

4.2 20-Pin Connectors for Sierra Flow Meters/Controllers .......... 5

4.3 26-Pin I/O Connector ......................................................... 5

4.4 4.3.1 Flow Value Output 0-5 VDC and 4-20 mA ................ 5

TABLE OF

CONTENTS

4.4 4.3.2 Valve Off/Purge/Monitor ......................................... 5

4.4 4.3.3 High/Low Flow Alarm Outputs ................................ 6

4.4 Automatic/Manual Setpoint Selection .................................. 6

5. Maintenance ........................................................................... 7

5.1 Display Adjustment ........................................................... 7

5.2 Zen and Span Adjusted ...................................................... 7

5.3 Factory Service ................................................................. 7

Appendix A: Specifications ........................................................... 8

Appendix B: Back Panel Connector, 20-Pin .................................... 9

Appendix C: Back Panel Connector, 26-Pin .................................. 10

Appendix D: Alarms for System Electronics ..................................11

Appendix E: Wiring Guide ..........................................................12

Appendix F: Ratio Control Option ................................................13

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Series 900 Single & Dual Instruction Manual

The Sierra Instruments, Inc. Single and Dual Channel System
Electronics is a highly integrated systems solution to flow mea­surement and control.

One or two independent flow meters or controllers can be operated
simultaneously.

Linear operation with LCD readout is standard.

The back panel connectors provide outputs of 0-5 VDC and 4-20
mA and are 0-100% analogs of the flow range. Both voltage and
current outputs are simultaneously available.

Flow setpoint for flow controllers is from either the front panel
adjustment potentiometers or a remote source via the back panel
I/O interface. These potentiometers are only available on system
electronics which have a “C” as part of the model number (i.e.,
902C).

Side-Trak mass flow controllers also incorporate valve purge/
monitor/off functions which are accessible from the back panel
I/O connector.

Each channel has an optional high and/or low alarm (open collec­tor) output. The alarm adjustment pots are located inside the
system electronics box and can be read on the front panel display
during adjustment.

1

INTRODUCTION

An optional built-in totalizer on single channel configurations
displays the total mass flow. The electronic totalizer is highly
immune to power line interruptions.

The power supply is a linear (non-switching) laboratory quality
unit capable of easily supplying power to 2 channels simulta­neously.

Page 1

Series 900 Single & Dual Instruction Manual

The System Electronics should be located in a room-temperature
location which is dry and dust-free. Use cable lengths in accor­dance with the guidelines given with your transducer. Excessive
cable lengths will impair operation of both the System Electronics
and the transducer.

Extremes of temperature and direct sunlight should be avoided.

Choose a location which allows the readout to be easily viewed.

2

LOCATING SYSTEM

ELECTRONICS

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Series 900 Single & Dual Instruction Manual

System Electronics’s front panel controls provide ease of opera­tion. To get the most benefit from a Sierra Instruments, Inc.
System Electronics, read these instructions before attempting
operation.

On dual channel units, the rotary switch labeled Channel Select
determines which channel is displayed.

The flow value is normally read from the LCD Display. Readout
is usually in engineering units and is indicated on the label.

System Electronics toggles between flow reading and flow setpoint
by the switch labeled “SET/READ”. When in the READ mode, the
display shows flow value as above. When in the SET mode, the
display shows the current setpoint value in the same units as the
“READ” mode.

For each channel, there is an optional high alarm and/or low
alarm. Each alarm output is active whenever the flow is above or
below the preset value, respectively. All alarm outputs are OPEN
COLLECTOR NPN and sink current to COMMON. If driving a
relay, a reverse polarity protection diode must be connected across
the coil. See appendix D for additional information regarding the
alarms.

3

FRONT PANEL

FUNCTIONS

3.1

Channel Selection

3.2

Reading Flow Value

3.3

Flow Setpoint Display

and Adjustment

(Controllers Only)

3.4

High/Low Alarm Display

and Adjustment

When the flow is below the low alarm set value, the low alarm is
active. (Alarm is ON).

When the flow value is greater than the high alarm set value, the
high alarm is active. (Alarm is ON).

The alarm adjustments are located internally. The front bezel
must first be removed by unscrewing the four black screws
holding it in place, then sliding the top cover out to expose the
main printed circuit board. See the drawing in Appendix G giving
the location of the alarm component.

The alarm display is activated using internal switches. These
switches are located near the front panel. The switch labeled ALM
or NORM shows the alarm setting on the front panel display. The
toggle switch labeled HI/LO selects whether the high or low alarm
is displayed. This switch must be held at the ALM position while
adjusting the alarm point with the switch in the ALM position, the
LCD display will show the alarm value.

The alarm adjustment potentiometers are located toward the rear
of the main PCB. As you face the front of the unit, Channel 1 is on
the right and Channel 2 is on the left. The high alarm pots are
marked R29 and the low alarm pots are marked R33.

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