Racal Instruments 2251A User manual

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VXI REVISION 1.4
OPERATOR’S MANUAL
2251A
UNIVERSAL TIMER/COUNTER
PUBLICATION NO. 980789
RACAL INSTRUMENTS
Racal Instruments, Inc.
4 Goodyear St., Irvine, CA 92718-2002
Tel: (800) RACAL-ATE, (949) 859- 8999, FAX: [phone]
Racal Instruments, Ltd.
480 Bath Road, Slough, Berkshire, SL1 6BE, United Kingdom
Tel: [phone]; FAX: [phone]
Racal Systems Electronique
18 Avenue Dutartre, 78150 LeChesnay, France
Tel: [phone]; FAX: [phone]
Racal Systems Elettronica Srl.
Strada 2-Palazzo C4, 20090 Milanofiori Assago, Milan, Italy
Tel: [phone]; FAX [phone]
Racal Elektronik System GmbH.
Frankenforster Strasse 21, 51427 Bergisch-Gladbach 1, Germany
Tel:[phone]; FAX: [phone]
Racal Australia Pty. Ltd.
3 Powells Road, Brookvale, NSW 2100, Australia
Tel: [phone], FAX: [phone]
Racal Electronics Pte. Ltd.
26 Ayer Rajah Crescent, 04-06/07 Ayer Rajah Industrial Estate, Singapore 0513.
Tel: [phone], FAX: [phone]
Racal Instruments, Ltd.
Room 1213 Nan Fung Centre, Tsuen Wan, New Territories, Hong Kong
Tel: [phone], FAX: [phone]
http://www.racalinst.com
PUBLICATION DATE: SEPTEMBER 1998
Copyright 1998 by Racal Instruments, Inc. Printed in the United States of America. All rights reserved.
This book or parts thereof may not be reproduced in any form without written permission of the publisher.
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WARRANTY STATEMENT
All Racal Instruments, Inc. products are designed and manufactured to exacting standards and in full
conformance to Racal’s ISO 9001 procedures.
For the specific terms of your standard warranty, or optional extended warranty or service agreement, contact
your Racal customer service advisor. Please have the following information available to facilitate service.
1. Product serial number
2. Product model number
3. Your company and contact information
You may contact your customer service advisor by:
E-Mail: [email protected]
Telephone: [phone] (USA)
[phone] (UK)
[phone] (Hong Kong)
Fax: [phone] (USA)
[phone] (UK)
[phone] (Hong Kong)
RETURN of PRODUCT
Authorization is required from Racal Instruments before you send us your product for service or calibration. Call
your nearest Racal Instruments support facility. A list is located on the last page of this manual. If you are
unsure where to call, contact Racal Instruments, Inc. Customer Support Department in Irvine, California, USA at
1-800-722-3262 or 1-949-859-8999 or via fax at 1-949-859-7139. We can be reached at:
[email protected].
PROPRIETARY NOTICE
This document and the technical data herein disclosed, are proprietary to Racal Instruments, and shall not,
without express written permission of Racal Instruments, be used, in whole or in part to solicit quotations from a
competitive source or used for manufacture by anyone other than Racal Instruments. The information herein has
been developed at private expense, and may only be used for operation and maintenance reference purposes or
for purposes of engineering evaluation and incorporation into technical specifications and other documents which
specify procurement of products from Racal Instruments.
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FOR YOUR SAFETY
Before undertaking any troubleshooting, maintenance or exploratory procedure, read
carefully the WARNINGS and CAUTION notices.
This equipment contains voltage hazardous to human life and safety, and is capable of
inflicting personal injury.
If this instrument is to be powered from the AC line (mains) through an autotransformer,
ensure the common connector is connected to the neutral (earth pole) of the power
supply.
Before operating the unit, ensure the conductor (green wire) is connected to the ground
(earth) conductor of the power outlet. Do not use a two-conductor extension cord or a
three-prong/two-prong adapter. This will defeat the protective feature of the third conductor
in the power cord.
Maintenance and calibration procedures sometimes call for operation of the unit with
power applied and protective covers removed. Read the procedures and heed warnings to
avoid “live” circuit points.
Before operating this instrument:
1. Ensure the instrument is configured to operate on the voltage at the power source. See
Installation Section.
2. Ensure the proper fuse is in place for the power source to operate.
3. Ensure all other devices connected to or in proximity to this instrument are properly
grounded or connected to the protective third-wire earth ground.
If the instrument:
-fails to operate satisfactorily
-shows visible damage
-has been stored under unfavorable conditions
-has sustained stress
Do not operate until performance is checked by qualified personnel.
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i
OPERATORS MANUAL
TABLE OF CONTENTS
MODEL 2251A
SECTION 1 GENERAL INFORMATION ...................... 1-1
1.1 Introduction ..................................... 1-1
1.2 Measurement Functions ............................ 1-2
1.3 Input Signal Conditioning .......................... 1-3
1.4 Options......................................... 1-4
1.5 PerformanceSpecifications ......................... 1-5
1.6 DefinitionsandNotes ............................. 1-14
1.7 Safety .......................................... 1-17
1.8 Product Support .................................. 1-17
SECTION 2 INSTALLATION ................................ 2-1
2.1 Introduction ..................................... 2-1
2.2 UnpackingandInspection .......................... 2-1
2.3 ReshipmentInstructions ........................... 2-1
2.4 Interrupt Level and Logical Address Setting ............ 2-1
2.5 Installation ...................................... 2-2
SECTION 3 USING THE INSTRUMENT ...................... 3-1
3.1 VXIbusControl .................................. 3-1
3.2 VXIbus Logical Address and Interrupt Level Assignment . 3-1
3.3 2251A Home State ................................ 3-2
3.4 FunctionalCheck................................. 3-3
3.5 Output Message Format ............................ 3-4
3.6 Input Commands ................................. 3-6
3.7 Selecting the Measurement Function .................. 3-11
3.8 Numerical Input Data .............................. 3-12
3.9 ResolutionControlSelection........................ 3-13
3.10 Signal Conditional Parameters ....................... 3-14
3.11 Measurement Control Codes ........................ 3-15
3.12 Store and Recall Codes ............................ 3-16
3.13 Special Functions ................................. 3-17
3.14 2251A Supported IEEE-488.2 Commands ............. 3-20
3.15 2251A IEEE-488.2 Status Reporting Structure Requiremnts 3-22
3.16 Device Dependent Status Bit (DDSB) ................. 3-23
3.17 Error Messages .................................. 3-25
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ii
TABLE OF CONTENTS (Continued)
SECTION 4 PERFORMANCE VERIFICATION ................ 4-1
4.1 Performance Verification Procedures (PVPs) .......... 4-1
4.2 FunctionalChecks ................................ 4-14
4.3 Disassembly Instructions .......................... 4-17
4.4 Reassembly Instructions ........................... 4-17
4.5 2251A Input Amplifier Setup Procedure .............. 4-18
SECTION 5 APPLICATION NOTES .......................... 5-1
5.1 ProgrammingDefaultsinAutomaticFunctions ......... 5-1
5.2 Calculating Measurement Cycle Time ................ 5-8
SECTION 6 OPTIONAL CABLE ASSEMBLIES ................ 6-1
FIGURES
1.1 2251A Resident In a VXIbus Compatible Mainframe .... 1-1
2.1 LocationofSwitches .............................. 2-2
3.1 IEEE-488.2 Status Reporting Model .................. 3-22
4.1 Input A Low Frequency Sensitivity Test Configuration . . . 4-3
4.2 Input A High Frequency Sensitivity Test Configuration . . . 4-4
4.3 Input B Low Frequency Sensitivity Test Configuration . . . 4-5
4.4 Input B High Frequency Sensitivity Test Configuration . . . 4-6
4.5 Input C Test Configuration ......................... 4-7
4.6 Time Interval A-B Test Configuration ................ 4-8
4.7 TotalizeAbyBTestConfiguration .................. 4-9
4.8 RatioA/BTestConfiguration ....................... 4-10
4.9 RatioC/BTestConfiguration ....................... 4-11
4.10 Input A Trigger Level Test Configuration .............. 4-12
4.11 Input B Trigger Level Test Configuration .............. 4-13
4.12 Input A Filter Check Configuration ................... 4-14
4.13 Input A X10 Attenuator Check Configuration .......... 4-15
4.14 Input B X10 Attenuator Check Configuration ........... 4-16
4.15 Location of R10, R11, R12 and R15 .................. 4-18
4.16 Input A Amplifier Setup Configuration ................ 4-19
4.17 Input B Amplifier Setup Configuration ................ 4-20
4.18 Input C Setup Configuration ........................ 4-21
5.1 Positive/Negative Pulse ............................ 5-2
5.2 Rise/Fall Time ................................... 5-2
5.3 Phase Measurements .............................. 5-6
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iii
TABLE OF CONTENTS (Continued)
TABLES
3.1 2251A Home State ................................ 3-2
3.2 2251A Measurement Mode Output Strings ............. 3-5
3.3 2251A Recalled Data Output Strings ................. 3-6
3.4 Permitted Terminators ............................. 3-7
3.5 Instrument Preset Condition ........................ 3-8
3.6 Instrument Preset Code ............................ 3-9
3.7 Numerical Input Format ............................ 3-10
3.8 Measurement Function Codes ....................... 3-11
3.9 Numerical Input Ranges ........................... 3-12
3.10 Resolution Control Selection ........................ 3-13
3.11 Input Control Codes ............................... 3-14
3.12 Measurement Control Codes ........................ 3-15
3.13 Store and Recall Codes ............................ 3-16
3.14 Special Function Codes ............................ 3-18
3.15 Using the Special Function ......................... 3-19
3.16 IEEE-488.2 Command Codes ....................... 3-20
3.17 STA Related “Q” Codes ........................... 3-23
3.18 2251A STA Response Description ................... 3-24
3.19 2251A STA Error Code Set ......................... 3-25
3.20 Alphabetical List of 2251A Command Codes ........... 3-26
4.1 Input A Sensitivity Low Frequency Test ............... 4-3
4.2 Input A Sensitivity High Frequency Performance Limits . . 4-4
4.3 Input B Sensitivity Low Frequency Performance Limits . . 4-5
4.4 Input B Sensitivity High Frequency Performance Limits . . 4-6
4.5 Input C Sensitivity Performance Limits ............... 4-7
4.6 Time Interval A-B Test Performance Limits ............ 4-8
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iv
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1-1
SECTION 1 GENERAL INFORMATION
1.1 Introduction
1.1.1 The Racal Instruments Universal Counter Timer Model 2251A is a microprocessor
controlled instrument offering high resolution measurement capabilities. The 2251A
is designed to be used under the direction of the Slot 0 System Resource Manager of
aVXIbus compatible mainframe. The 2251A conforms to VXIbus System
Specification Revision 1.4.
1.1.2 The measurement capabilities of the 2251A may be extended to include frequency
measurements to 1.3 GHz with Option 41.
1.1.3 The 2251A is designed to be controlled remotely over the VXIbus. No local control
of the counter is possible. The command set the counter responds to is defined by
Racal Instruments. Refer to Section 3 of this manual for details of this command set.
1.1.4 Refer to Figure 1-1 for an illustration of the 2251A in a VXI mainframe.
Figure 1-1. Model 2251A Resident In a VXIbus Compatible Mainframe.
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