Tektronix TX3, TX1 Service Manual

Service Manual

TX1 and TX3
True RMS Digital Multimeter

070-9893-01

Warning

The servicing instructions are for use by qualified
personnel only. To avoid personal injury, do not
perform any servicing unless you are qualified to
do so. Refer to all safety summaries prior to
performing service.

Copyright © T ektronix, Inc. All rights reserved.
T ektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes

that in all previously published material. Specifications and price change privileges reserved.
Printed in the U.S.A.
T ektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070–1000
TEKTRONIX and TEK are registered trademarks of T ektronix, Inc.

WARRANTY

T ektronix warrants that the products that it manufactures and sells will be free from defects in materials and workmanship
for a period of three (3) years from the date of shipment. If a product proves defective during this warranty period,
T ektronix, at its option, either will repair the defective product without charge for parts and labor, or will provide a
replacement in exchange for the defective product.

In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the
warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for
packaging and shipping the defective product to the service center designated by T ektronix, with shipping charges prepaid.
T ektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which the
T ektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any
other charges for products returned to any other locations.

This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate
maintenance and care. T ektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting
from attempts by personnel other than T ektronix representatives to install, repair or service the product; b) to repair
damage resulting from improper use or connection to incompatible equipment; c) to repair any damage or malfunction
caused by the use of non-T ektronix supplies; or d) to service a product that has been modified or integrated with other
products when the effect of such modification or integration increases the time or difficulty of servicing the product.

THIS WARRANTY IS GIVEN BY TEKTRONIX IN LIEU OF ANY OTHER WARRANTIES, EXPRESS OR
IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PAR TICULAR PURPOSE. TEKTRONIX’ RESPONSIBILITY TO
REP AIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO
THE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BE
LIABLE FOR ANY INDIRECT , SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE
OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH
DAMAGES.

Service Assurance

If you have not already purchased Service Assurance for this product, you may do so at any time during the product’s
warranty period. Service Assurance provides Repair Protection and Calibration Services to meet your needs.

Repair Protection extends priority repair services beyond the product’s warranty period; you may purchase up to three
years of Repair Protection.

Calibration Services provide annual calibration of your product, standards compliance and required audit documentation,
recall assurance, and reminder notification of scheduled calibration. Coverage begins upon registration; you may purchase
up to five years of Calibration Services.

Service Assurance Advantages

H Priced well below the cost of a single repair or calibration
H Avoid delays for service by eliminating the need for separate purchase authorizations from your company
H Eliminates unexpected service expenses

For Information and Ordering

For more information or to order Service Assurance, contact your T ektronix representative and provide the information
below . Service Assurance may not be available in locations outside the United States of America.

Name VISA or Master Card number and expiration
Company date or purchase order number
Address Repair Protection (1,2, or 3 years)
City , State, Postal code Calibration Services (1,2,3,4, or 5 years)
Country Instrument model and serial number
Phone Instrument purchase date

Table of Contents

Specifications

Operating Information

General Safety Summary v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Service Safety Summary vii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Preface ix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Manual Structure ix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Manual Conventions x. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Related Manuals x. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contacting T ektronix x. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Introduction xi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Service Strategy xi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Service Offerings xi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Before You Begin xii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Specifications 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating Information 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Front and Rear Panel Overview 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Display Indicators 2–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Measurement Function Knob 2–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Input Connectors 2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Button and Softkey Overview 2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Softkeys 2–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Setup Menu 2–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Battery Replacement 2–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Theory of Operation

Theory of Operation 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Performance Verification

Performance Verification 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

T est Equipment 4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Set Up 4–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Verification Procedure 4–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TX1 Test Record 4–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TX3 Test Record 4–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Adjustment Procedure

Adjustment Procedure 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Options

Options 6–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TX1 and TX3 True RMS Digital Multimeter Service Manual

i

Table of Contents

Maintenance

Replaceable Parts

Maintenance 7–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Related Maintenance Procedures 7–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Preparation 7–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Inspection and Cleaning 7–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Disassembly and Assembly Procedures 7–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Troubleshooting 7–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Repackaging Instructions 7–22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Replaceable Parts 8–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Parts Ordering Information 8–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Using the Replaceable Parts List 8–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ii

TX1 and TX3 True RMS Digital Multimeter Service Manual

List of Figures

Table of Contents

Figure 2–1: Front panel overview 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 2–2: Rear panel overview 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 2–3: Display indicators 2–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 2–4: Measurement function knob 2–4. . . . . . . . . . . . . . . . . . . . . . .

Figure 2–5: Input connectors 2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 2–6: Battery replacement 2–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 3–1: Simple block diagram 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 7–1: Opening and closing the case 7–6. . . . . . . . . . . . . . . . . . . . . . .

Figure 7–2: Internal assembly removal and installation 7–8. . . . . . . . . . .

Figure 7–3: Battery holder removal and installation 7–9. . . . . . . . . . . . . .

Figure 7–4: LCD bezel removal and installation 7–10. . . . . . . . . . . . . . . . .

Figure 7–5: LCD removal and installation 7–11. . . . . . . . . . . . . . . . . . . . . .

Figure 7–6: Circuit board tabs 7–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 7–7: Circuit board removal and installation 7–13. . . . . . . . . . . . . .

Figure 7–8: Light diffuser removal and installation 7–14. . . . . . . . . . . . . .

Figure 7–9: Function knob removal 7–16. . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 7–10: Function knob and switch keypad installation 7–17. . . . . . .

Figure 7–11: Troubleshooting start 7–19. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 7–12: Troubleshooting two 7–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 7–13: Troubleshooting three 7–21. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 8–1: Exploded view 8–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TX1 and TX3 True RMS Digital Multimeter Service Manual

iii

Table of Contents

List of Tables

Table 1–1: General characteristics 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–2: DC voltage characteristics 1–2. . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–3: DC voltage range, resolution, and accuracy 1–2. . . . . . . . . . .

Table 1–4: AC voltage characteristics 1–2. . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–5: AC voltage range, resolution, and accuracy 1–3. . . . . . . . . . .

Table 1–6: DC current characteristics 1–4. . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–7: DC current range, resolution, and accuracy 1–4. . . . . . . . . . .

Table 1–8: AC current characteristics 1–4. . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–9: AC current range, resolution, and accuracy 1–5. . . . . . . . . . .

Table 1–10: Resistance (W) characteristics 1–5. . . . . . . . . . . . . . . . . . . . . .

Table 1–11: Resistance range, resolution, and accuracy 1–6. . . . . . . . . . .

Table 1–12: Continuity characteristics 1–6. . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–13: Diode test characteristics 1–7. . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–14: Capacitance range, resolution, and accuracy

(5,000 counts only) 1–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–15: Frequency characteristics, resolution, and accuracy 1–7. . .

Table 1–16: Frequency voltage range 1–8. . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–17: Duty factor characteristics 1–8. . . . . . . . . . . . . . . . . . . . . . . .

Table 1–18: Temperature characteristics 1–8. . . . . . . . . . . . . . . . . . . . . . .

Table 1–19: 1ms peak hold characteristics 1–8. . . . . . . . . . . . . . . . . . . . . .

Table 1–20: Physical characteristics 1–9. . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–21: Environmental characteristics 1–9. . . . . . . . . . . . . . . . . . . . .

Table 1–22: Certifications and compliances 1–9. . . . . . . . . . . . . . . . . . . . .

Table 2–1: Setup prompts, definitions, and default values 2–9. . . . . . . . .

Table 4–1: Performance verification checks 4–1. . . . . . . . . . . . . . . . . . . .

Table 4–2: Test equipment 4–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 4–3: TX1 test record results 4–11. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 4–4: TX3 test record results 4–15. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 7–1: Relative susceptibility to static-discharge damage 7–3. . . . . .

Table 7–2: List of tools 7–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 8–1: Parts list column descriptions 8–2. . . . . . . . . . . . . . . . . . . . . . .

Table 8–2: Manufacturers cross index 8–3. . . . . . . . . . . . . . . . . . . . . . . . .

Table 8–3: Replaceable parts list 8–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 8–4: Standard accessories 8–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 8–5: Optional accessories 8–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

iv

TX1 and TX3 True RMS Digital Multimeter Service Manual

General Safety Summary

Review the following safety precautions to avoid injury and prevent damage to
this product or any products connected to it. To avoid potential hazards, use this
product only as specified.

Only qualified personnel should perform service procedures.

To Avoid Fire or
Personal Injury

Connect and Disconnect Properly . Do not connect or disconnect probes or test

leads while they are connected to a voltage source.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings

and markings on the product. Consult the product manual for further ratings
information before making connections to the product.

Do not apply a potential to any terminal, including the common terminal, that
exceeds the maximum rating of that terminal.

Replace Batteries Properly. Replace batteries only with the proper type and rating
specified.

Do Not Operate Without Covers. Do not operate this product with covers or panels
removed.

Use Proper Fuse. Use only the fuse type and rating specified for this product.
Avoid Exposed Circuitry. Do not touch exposed connections and components

when power is present.
Do Not Operate With Suspected Failures. If you suspect there is damage to this

product, have it inspected by qualified service personnel.

Do Not Operate in Wet/Damp Conditions.
Do Not Operate in an Explosive Atmosphere.
Keep Product Surfaces Clean and Dry .

Symbols and Terms

TX1 and TX3 True RMS Digital Multimeter Service Manual

T erms in this Manual. These terms may appear in this manual:

WARNING. Warning statements identify conditions or practices that could result
in injury or loss of life.

CAUTION. Caution statements identify conditions or practices that could result in
damage to this product or other property.

v

General Safety Summary

T erms on the Product. These terms may appear on the product:
DANGER indicates an injury hazard immediately accessible as you read the

marking.
WARNING indicates an injury hazard not immediately accessible as you read the

marking.
CAUTION indicates a hazard to property including the product.
Symbols on the Product. The following symbols may appear on the product:

CAUTION

Refer to Manual

WARNING

High Voltage

Double

Insulated

vi

TX1 and TX3 True RMS Digital Multimeter Service Manual

Service Safety Summary

Only qualified personnel should perform service procedures. Read this Service
Safety Summary and the General Safety Summary before performing any service

procedures.
Do Not Service Alone. Do not perform internal service or adjustments of this

product unless another person capable of rendering first aid and resuscitation is
present.

Use Care When Servicing With Power On. Dangerous voltages or currents may
exist in this product. Disconnect power, remove battery (if applicable), and
disconnect test leads before removing protective panels, soldering, or replacing
components.

To avoid electric shock, do not touch exposed connections.

TX1 and TX3 True RMS Digital Multimeter Service Manual

vii

Service Safety Summary

viii

TX1 and TX3 True RMS Digital Multimeter Service Manual

Preface

Manual Structure

This section contains information needed to properly use this manual to service
the TX1 and TX3 True RMS Digital Multimeters as well as general information
critical to safe and effective servicing of multimeters.

This manual is divided into chapters, such as Specifications and Theory of
Operation. Further, it is divided into subsections, such as Product Description
and Disassembly and Assembly Procedures.

Sections containing procedures also contain introductions to those procedures. Be
sure to read these introductions because they provide information needed to do
the service correctly and efficiently. The following is a brief description of each
manual chapter.

H Specifications contains a product description and tables of the characteristics

and descriptions that apply to it.

H Operating Information includes general information and operating instruc-

tions at the level needed to safely service the multimeters. A statement of the
service strategy is in this section.

H Theory of Operation contains circuit descriptions down to the module level.
H Performance Verification contains a collection of procedures for confirming

that the multimeters function properly and meet warranted limits.

H Adjustment Procedure informs you how to obtain calibration services.
H Options lists the available options for the TX1 and TX3 meters.
H Maintenance contains information and procedures for doing preventive and

corrective maintenance. This includes cleaning instructions and disassembly
and assembly instructions.

H Replaceable Parts includes a table of all replaceable parts, their descriptions,

and their Tektronix part numbers.

TX1 and TX3 True RMS Digital Multimeter Service Manual

ix

Preface

Manual Conventions

This manual uses certain conventions which you should become familiar with
before doing service.

Safety

Symbols

Related Manuals

Contacting Tektronix

Symbols and terms related to safety appear in the Safety Summary found at the
beginning of this manual.

Refer to the Safety section in this manual to learn about the symbols used in this
manual.

The TX1 and TX3 digital multimeters are shipped with a user manual. Refer to
the user manual for detailed operating instructions.

Product
Support

For application-oriented questions about a Tektronix measure­ment product, call toll free in North America:
1-800-TEK-WIDE (1-800-835-9433 ext. 2400)
6:00 a.m. – 5:00 p.m. Pacific time

Or, contact us by e-mail:
[e-mail]

For product support outside of North America, contact your
local Tektronix distributor or sales office.

Service
Support

For other
information

To write us Tektronix, Inc.

x

Contact your local Tektronix distributor or sales office. Or, visit
our web site for a listing of worldwide service locations.

http://www.tektronix.com
In North America:

1-800-TEK-WIDE (1-800-835-9433)
An operator will direct your call.

P.O. Box 1000
Wilsonville, OR 97070-1000

TX1 and TX3 True RMS Digital Multimeter Service Manual

Introduction

Service Strategy

Service Offerings

This manual contains all the information needed for periodic maintenance of the
TX1 and TX3 True RMS Digital Multimeters.

All replaceable parts are listed in Table 8–3 Replaceable parts list. To remove and
replace any parts, follow the instructions in Dissasembly and Assembly Proce-
dures found in Chapter 7.

Tektronix provides service to cover repair under warranty as well as other
services that may provide a cost-effective answer to your service needs.

Whether providing warranty repair service or any of the other services listed
below, Tektronix service technicians, trained on Tektronix products, are best
equipped to service your TX1 and TX3 True RMS Digital Multimeters.
Tektronix technicians are apprised of the latest information on improvements to
the product as well as the latest options to the product.

Warranty Repair Service

Repair or Calibration

Service

Tektronix warrants this product for three years from date of purchase. (The
warranty appears after the title page and copyright page in this manual.)
Tektronix technicians provide warranty service at most Tektronix service
locations worldwide. Your Tektronix product catalog lists all service locations
worldwide.

The following services may be purchased to tailor repair and/or calibration of
your TX1 and TX3 True RMS Digital Multimeters to fit your requirements.

At-Depot Service. Tektronix offers several standard-priced adjustment (calibra­tion) and repair services:

H A single repair and/or adjustment.
H Calibrations using equipment and procedures that meet the traceability

standards specific to the local area.

H Annual maintenance agreements that provide for either calibration and repair

or calibration only.

TX1 and TX3 True RMS Digital Multimeter Service Manual

xi

Introduction

Of these services, the annual maintenance agreement offers a particularly
cost-effective approach to service for many owners. Such agreements can be
purchased to span several years.

Self Service

Before You Begin

Tektronix supports self service repair by providing replaceable parts. See the
Replaceable Parts chapter for a list of all replaceable parts.

This manual is for servicing the TX1 and TX3 True RMS Digital Multimeters.
To prevent injury to yourself or damage to the meter, do the following tasks
before you attempt service:

H Read the Safety Summary found at the beginning of this manual.
H Read Service Strategy in this section.

When using this manual for servicing, be sure to read and follow all warnings,
cautions, and notes.

xii

TX1 and TX3 True RMS Digital Multimeter Service Manual

Specifications

Specifications

All specifications are warranted, unless noted as typical, for the rated tempera­ture range of 23_ C

± 5_ C at less than 80% relative humidity.

T able 1–1: General characteristics

Characteristics Description

LCD display digits 3$@5 (default) or 4$@5

Display counts 5,000 (default) or 50,000

Bargraph 20 segment, updated 20 times per second

Memory locations TX1: 10, TX3: 30

Out of range indicator OL: overrange

Ur: underrange

Low voltage indicator Battery symbol shows on LCD at 2.0 V .

Meter powers down at 1.5 V .
Battery life 100 hours continuous use with backlight off (typical)
Auto-off Adjustable, 30 minute default
Power source Two AA 1.5 V alkaline batteries (IEC LRG or ANSI/NEDA

15A)
Maximum input voltage be-

tween terminals and between
terminals and earth

Maximum open circuit voltage
when utilizing the A terminal

Overload protection, V terminal 1000 V
F1 fuse protection 15 A (1000 V) fast
Backlight Green LEDs

1

If meter is exposed to water, have it inspected by qualified service personnel.

1000 V

600 V

Installation Category III (CAT III)

RMS

CAT III

RMS

(1500 Vpk) for all functions

RMS

1

TX1 and TX3 True RMS Digital Multimeter Service Manual

1–1

Specifications

R

e

T able 1–2: DC voltage characteristics

Characteristic Description

Settling time 3 readings (typical)
Reading rate 5,000 ct.: 4 readings per second

50,000 ct.: 1 reading per second

Rejection ratio

Common mode 120 dB at DC or 50 Hz or 60 Hz
Normal mode 60 dB at 50 Hz or 60 Hz

Input impedance 10 MW (typical)

T able 1–3: DC voltage range, resolution, and accuracy

Resolution Accuracy

1

ang

0.5 V 100 mV 10 mV
5 V 1 mV 100 mV

5,000 counts 50,000 counts TX1 TX3

± (0.07% + 1 ± (0.05% + 1
count) count)

50 V 10 mV 1 mV
500 V 100 mV 10 mV
1000 V 1 V 100 mV
T emperature coef ficient Add (0.005% + 0.1 ct.)/°C to accuracy

beyond rated temperature range.

1

Accuracy in 50,000-count mode is % + 10 counts.

T able 1–4: AC voltage characteristics

Characteristic Description

Input impedance 10 MW in parallel with <100 pF (typical)
Settling time 4 readings (typical)
Reading rate 5,000 ct.: 4 readings per second

50,000 ct.: 1 reading per second

Common mode

60 dB at DC to 60 Hz

rejection ratio
Crest factor, maximum Full scale: 3

Half scale: 6

1

AC+DC

total RMS volts

AC (RMS) accuracy + 0.1% + 1 count

accuracy

1–2

TX1 and TX3 True RMS Digital Multimeter Service Manual

T able 1–4: AC voltage characteristics (cont.)

R

e

±

±

s

s

Characteristic Description

1

AC DC

Upper display frequency
(5,000 counts)

dB reference
dBm reference

1
2

dual display accuracy DC Accuracy + 0.05% + 1 count

AC RMS Accuracy + 0.1% + 1 count

Accuracy ±(0.002% + 1 count) for 20 Hz to 20 kHz
Sensitivity 10% of selected voltage range

2

2

1 V

(adjustable)

RMS

775 mV across 600 W (1 mW)

5,000-count mode only.
dB readout = 20 log (main display readout/ref), where ref = 1 V is the default.

dBm readout = 10 log (main display readout2/R), where R=600 W.

Specifications

T able 1–5: AC voltage range, resolution, and accuracy

Resolution Accuracy

ang

0.5 V 100 mV 10 mV
5 V 1 mV 100 mV

5,000 counts 50,000 counts TX1 TX3

40 Hz – 20 kHz:

(0.6% + 2

counts)

50 V 10 mV 1 mV

2

500 V
1000 V

100 mV 10 mV

2

1 V 100 mV 40 Hz – 10 kHz:

± (0.6% + 2
counts)

T emperature coef ficient AC: Add (0.03% + 0.1 ct.)/°C beyond

rated temperature range.
AC+DC: Add (0.06% + 0.1 ct.)/°C

beyond rated temperature range.

1

Accuracy in 50,000-count mode is % + 20 counts.

2

For voltages u 100 V , the maximum volts–Hz product is t 10 MVHz.

1

40 Hz – 20 kHz:

(0.4% + 2

counts)

40 Hz – 10 kHz:
± (0.4% + 2
counts)

TX1 and TX3 True RMS Digital Multimeter Service Manual

1–3

Specifications

R

e

2

T able 1–6: DC current characteristics

Characteristics Description

Burden voltage 5 mA to 5 A: 0.3 V max.

10 A: 0.5 V max.

Percent 4-20 mA (calculated in
50 mA range)

4 mA = 0%

20 mA = 100%
Settling time 4 readings (typical)
Reading rate 5,000 ct.: 4 readings per second

50,000 ct.: 1 reading per second

T able 1–7: DC current range, resolution, and accuracy

Resolution Accuracy

ang

500 A 100 nA 10 nA ± (0.2% + 4 counts)
5 mA 1 A 100 nA
50 mA 10 A 1 A
500 mA 100 A 10 A
5 A 1 mA 100 A ± (0.4% + 2 counts)
10 A

(15 A for
3 minutes)

5,000 counts 50,000 counts TX1 TX3

± (0.2% + 2 counts)

10 mA 1 mA ±(0.8% + 2 counts)

1

2
2

1–4

T emperature coef ficient Add (0.05% + 0.1 ct.)/°C beyond rated

temperature range.

1

Accuracy in 50,000-count mode is % + 40 counts.

2

Accuracy in 50,000-count mode is % + 20 counts.

T able 1–8: AC current characteristics

Characteristics Description

Burden voltage 0.5 mA to 5 A: 0.9 V max.

10 A: 1.0 V max.

1

AC+DC

Accuracy AC RMS amps accuracy + DC amps accuracy

Upper display frequency

Accuracy ±(0.002% + 1 count) for 20 Hz to 5 kHz
Sensitivity 10% of range

TX1 and TX3 True RMS Digital Multimeter Service Manual

T able 1–8: AC current characteristics (cont.)

R

e

Characteristics Description

Settling time 4 readings (typical)
Reading rate 5,000 ct.: 4 readings per second

50,000 ct.: 1 reading per second

1

5,000-count mode only.

T able 1–9: AC current range, resolution, and accuracy

Specifications

Resolution Accuracy

ang

5,000 counts 50,000 counts TX1 TX3

0.5 mA 100 nA 10 nA
5 mA 1 mA 100 nA
50 mA 10 mA 1 mA

40 Hz – 1 kHz: ± (0.6% + 2 counts)
>1 kHz – 3 kHz: ± (1.0% + 2 counts)
>3 kHz – 5 kHz: ± (2.0% + 2 counts)

1,2

500 mA 100 mA 10 mA
5 A 1 mA 100 mA
10 A

10 mA 1 mA
(15 A for
3 minutes)

T emperature coef ficient Add (0.05% + 0.1 ct.)/°C beyond rated

temperature range.

1

Accuracy in 50,000-count mode is % + 20 counts.

2

5% of range.

T able 1–10: Resistance (W) characteristics

Characteristics Description

Update rate 5,000 ct.: 2 readings per second

50,000 ct.: 1 reading per second
50 MW: 1 reading per second

Settling time 50 W to 5 MW range: 3 readings (typical)

50 MW range: 4 readings (typical)
Compliance voltages (typical) 0.6 V (50 W and 500 W range is 1.3 V)
Common mode rejection ratio 60 dB at DC, 50 Hz, or 60 Hz
Normal mode rejection ratio 20 dB at  50 Hz

TX1 and TX3 True RMS Digital Multimeter Service Manual

1–5

Specifications

R

e

T able 1–11: Resistance range, resolution, and accuracy

Resolution Accuracy

ang

50  0.01 
500  0.1  0.01  ± (0.1% + 4 counts)
5 k 1  0.1 

5,000 counts 50,000 counts TX1 TX3

1

–– ± (0.1% + 10 counts)

± (0.1% + 2 counts)

2
3

50 k 10  1 
500 k 100  10 
5 M 1 k 100  ± (0.4% + 4 counts)
50 M 10 k

1

–– ± (1.0% + 4 counts)

2

2

T emperature coef ficient 50  to 500 k: Add (0.03% + 0.1

ct.)/°C beyond rated temperature range.
5 M to 50 M: Add (0.2% + 0.1 ct.)/°C

beyond rated temperature range.

1

5,000 count mode only.

2

Accuracy in 50,000-count mode is % + 40 counts.

3

Accuracy in 50,000-count mode is % + 20 counts.

T able 1–12: Continuity characteristics

Characteristics Description

Continuity threshold Beeper sounds when resistance is 100  or less (typical)
Response time 1 ms

T able 1–13: Diode test characteristics

Characteristics Description

Test current (typical) 0.35 mA
Test voltage 2.8 V maximum, open circuit
Accuracy ± 1.0%

1–6

TX1 and TX3 True RMS Digital Multimeter Service Manual

Specifications

R

e

Resoluti

1

T able 1–14: Capacitance range, resolution, and accuracy (5,000 counts
only)

Accuracy

ang

on

TX1 TX3

5 nF 1 pF ± (1.0% + 5 counts) (using D mode)
50 nF 10 pF ± (1.0% + 3 counts) (using D mode)

2

500 nF 100 pF

± (1.0% + 3 counts)
5 mF 1 nF
50 mF 10 nF

± (3.0% + 3 counts)
500 mF 100 nF
5 mF 1 mF
50 mF 10 mF
T emperature coef ficient Add (0.05% + 0.1 ct.)/°C beyond rated

temperature range.

1

5,000 count mode only.

2

1% of range.

T able 1–15: Frequency characteristics, resolution, and accuracy

Characteristics Description

Signal coupling AC
Minimum frequency 0.5 Hz
Maximum frequency 1 MHz
Accuracy ±(0.002%) + 1 count
Best resolution 10,000 count: 0.01 Hz

T emperature coef ficient Add 0.00004%/(°C)2 beyond rated temperature range.

T able 1–16: Frequency voltage range

Range Sensitivity, 10 Hz - 100 kHz Sensitivity, 1 MHz

500 mV 100 mV ––
5 V 500 mV 2 V
50 V 5 V 20 V

TX1 and TX3 True RMS Digital Multimeter Service Manual

100,000 count: 0.001 Hz

1

1–7

Specifications

T able 1–16: Frequency voltage range (Cont.)

Range Sensitivity, 1 MHz

Sensitivity, 10 Hz - 100 kHz

1

500 V 50 V ––

1

For voltages  100 V , the maximum volts–Hz product is  10 MVHz.

T able 1–17: Duty factor characteristics

Characteristics Description

Range 1 Hz to 100 kHz
Accuracy ±(0.1% + 0.05% per kHz) for 5 V input (logic signals only)
Signal coupling DC
Resolution 0.1%
Sensitivity 30% of range

T able 1–18: Temperature characteristics

Characteristics Description

Main display

Range –50_ C to +980_ C
Accuracy ±3_C

1

(typical)

Thermocouple type K

Upper display

Accuracy ± 3_C of ambient temperature (typical)

1

Use the water and ice offset calibration method on page 2–9 for accuracy to ±1.0 °C.

T able 1–19: 1ms peak hold characteristics

Characteristics Description

Accuracy

1

1

5,000-count mode only.

Specified voltage or current measurement ±30 counts of the
peak value of a single 1ms pulse.

1–8

TX1 and TX3 True RMS Digital Multimeter Service Manual

T able 1–20: Physical characteristics

Characteristic Description

Dimensions (H  W  D) 38 mm  88 mm  183 mm

(without holster)

Weight (with batteries) 383 g (13.5 oz)

With holster 539 g (1 lb 3 oz)

T able 1–21: Environmental characteristics

Characteristic Description

Temperature

Operating –10 to +50_ C
Non-operating (storage) –40 to +60_ C

Humidity –40 to +35_ C: 80%

+35 to +40_ C: 70%
+40 to +60_ C: 55%

Specifications

Altitude

Operating 2,000m (6,562 ft)

For altitudes from 2,000 m up to 5,000 m (16,404 ft) derate
voltage input to 600 VAC CAT III.

Non-operating (storage) 12,300 m (40,354 ft)

Vibration

Operating 2.66 g
Non-operating 3.48 g

, 5 to 500 Hz, 3 axes (10 minutes each)

RMS

, 5 to 500 Hz, 3 axes (10 minutes each)

RMS

TX1 and TX3 True RMS Digital Multimeter Service Manual

1–9

Specifications

T able 1–22: Certifications and compliances

Category Standards or description

EC Declaration of Conformity
– EMC

Australia/New Zealand Decla­ration of Conformity – EMC

Meets intent of Directive 89/336/EEC for Electromagnetic
Compatibility. Compliance was demonstrated to the following
specifications as listed in the Official Journal of the European
Union:

EN 55011 Class A Radiated Emissions
EN 50082-1 Immunity:

IEC 801-2 Electrostatic Discharge Immunity
IEC 801-3 RF Electromagnetic Field

Immunity

1

Add 25 counts (250 counts in 50,000 count mode) to
the accuracy specifications when in the presence of
an RF field as defined in IEC801–3.

2

Amps DC: Add 60 counts (600 counts in 50,000 count
mode) to the amps accuracy specifications when in
the presence of an RF field as defined in IEC801–3.

Complies with EMC provision of Radiocommunications Act
per the following standard(s):

1,2

AS/NZS 2064.1/2 Industrial, Scientific, and Medical
Equipment: 1992

EC Declaration of Conformity
– Low Voltage

Compliance was demonstrated to the following specification
as listed in the Official Journal of the European Union:

Low Voltage Directive 73/23/EEC, amended by 93/69/EEC
EN 61010-1/A2:1995

Safety requirements for electrical equipment for
measuring control, and laboratory use.

U.S. Nationally Recognized
Testing Laboratory Listing

UL31 11-1 – Standard for electrical measuring and test
equipment.

Canadian Certification CAN/CSA C22.2 No. 1010.1

Safety requirements for electrical equipment for
measurement, control, and laboratory use.

Additional Compliance IEC61010-1/A2:1995

Safety requirements for electrical equipment for
measurement, control, and laboratory use.

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TX1 and TX3 True RMS Digital Multimeter Service Manual