Tektronix DTM500 Series Use and care manual

Technical Reference
Handheld and Benchtop Instruments
Basic Service
061-4108-00
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 Tektronix, Inc. All rights reserved.
Tektronix 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.
Tektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070–1000
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

Handheld and Benchtop Instruments Basic Service i
Handheld and Benchtop Instruments Service Reference
Service information not provided in this manual may be available under separate
cover. See Table i for a complete list of Handheld and Benchtop Instruments
service documentation.
Table i: Handheld and Benchtop Instruments Service Manuals
Product Tektronix Part Number
212Oscilloscope 070-5053-00
214Oscilloscope 070-5055-00
214Storage Oscilloscope 070-1483-00
221Oscilloscope 070-1573-01
222Digital Storage Oscilloscope 070-7459-00
222ADSO:
B010100thru B039999
B040000and above 070-8330-00
070-8330-02
222PSPower Scout 070-8098-02
224Digital Storage Oscilloscope 070-8405-02
305DMM Oscilloscope 070-2423-01
314Storage Oscilloscope 070-1824-00
335Oscilloscope 070-1943-01
336Digital Storage Oscilloscope 070-4421-00
2201PortableOscilloscope 070-7189-00
2205Oscilloscope 070-6716-00
2211Oscilloscope 070-7234-00
2214Digital Storage Oscilloscope 070-7783-00
2220Digital Storage Oscilloscope 070-5302-00
2221AOscilloscope:
B010100to B019999
B020000and above 070-8157-01
070-8549-00
2225Oscilloscope 070-6299-00
2230Digital Storage Oscilloscope 070-4999-00
2232Digital Storage Oscilloscope:
B010100to B029999
B030000and above 070-7067-01
070-8548-00
2235AN/USM-488Oscilloscope 070-4977-00

Handheld and Benchtop Instruments Service Reference
ii Handheld and Benchtop Instruments Basic Service
Table i: Handheld and Benchtop Instruments Service Manuals (Cont.)
Product Tektronix Part Number
2245PortableOscilloscope 070-6276-00
2245APortableOscilloscope:
B010100to B015999
B016000and above 070-6557-00
070-7672-00
2246APortableOscilloscope 070-6555-00
2246/1Y/2R/2246Mod A 070-7062-00
2247APortableOscilloscope 070-6367-00
2252PortableOscilloscope 070-7838-01
2335Oscilloscope 070-4116-00
2336Oscilloscope 070-4118-00
2336YAOscilloscope 070-5011-00
2337Oscilloscope 070-4120-00
TAS 455/465 Oscilloscope 070-8524-02
TAS 465 Oscilloscope 070-9403-00
TAS 475/485 Oscilloscope:
B010100to B020099
B020100and above 070-8878-01
070-9404-00
TDS210 Oscilloscope
TDS 220 070-9693-00
TDS310 Oscilloscope
TDS 320
TDS 350
070-8570-05
TDS340 Oscilloscope
TDS340A
TDS 360
TDS 380
070-9435-02
THS710 Oscilloscope
THS 720
THS 730
070-9246-03

Handheld and Benchtop Instruments Basic Service iii
General Safety Summary
Review the following safety precautions to avoid injury and prevent damage to
the products in this manual or any products connected to them. To avoid
potential hazards, use these products only as specified.
Only qualified personnel should perform service procedures.
While using these products, you may need to access other parts of the system.
Read the General Safety Summary in other system manuals for warnings and
cautions related to operating the system.
Use Proper Power Cord. To avoid fire hazard, use only the power cord specified
for the product you are using.
Use Proper Voltage Setting. Before applying power, ensure that the line selector is
in the proper position for the power source being used.
Connect and Disconnect Properly. Do not connect or disconnect probes or test
leads while they are connected to a voltage source.
Ground the Product. Some of these products are grounded through the grounding
conductor or the power cord. To avoid electric shock, the grounding conductor
must be connected to earth ground. Before making connections to the input or
output terminals of the product you are using, ensure that the product is properly
grounded.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings
and markings on the product you are using. 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.
Recharge Batteries Properly. Recharge batteries for the recommended charge
cycle only.
Use Proper AC Adapter. Use only the AC adapter specified for the product you
are using.
To Avoid Fire or
Personal Injury

General Safety Summary
iv Handheld and Benchtop Instruments Basic Service
Do Not Operate Without Covers. Do not operate these products with covers or
panels removed.
Use Proper Fuse. Use only the fuse type and rating specified for the product you
are using.
Avoid Exposed Circuitry. Do not touch exposed connections and components
when power is present.
Do Not Operate in Wet/Damp Conditions.To avoid electric shock, do not operate
these products in wet or damp conditions.
Do Not Operate in Explosive Conditions. To avoid injury or fire hazard, do not
operate these products in an explosive atmosphere.
Keep Product Surfaces Clean and Dry. To avoid electric shock and erroneous
readings, keep probe surfaces clean and dry.
Provide Proper Ventilation. Refer to the product installation instructions for details
on installing the product so it has proper ventilation.
Terms 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.
Terms on the Products. 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 and Terms

General Safety Summary
Handheld and Benchtop Instruments Basic Service v
Symbols on the Product. The following symbols may appear on the product:
ProtectiveGround
(Earth)Terminal ATTENTION Refer to Manual Double Insulated
DANGER
High Voltage

vi Handheld and Benchtop Instruments Basic Service
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.
Disconnect Power. To avoid electric shock, disconnect the main power by means
of the power cord or, if provided, the power switch.
Use Caution When Servicing the CRT. To avoid electric shock or injury, use
extreme caution when handling the CRT. Only qualified personnel familiar with
CRT servicing procedures and precautions should remove or install the CRT.
CRTs retain hazardous voltages for long periods of time after power is turned off.
Before attempting any servicing, discharge the CRT by shorting the anode to
chassis ground. When discharging the CRT, connect the discharge path to ground
and then the anode. Rough handling may cause the CRT to implode. Do not nick
or scratch the glass or subject it to undue pressure when removing or installing it.
When handling the CRT, wear safety goggles and heavy gloves for protection.
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.
X-Radiation. To avoid x-radiation exposure, do not modify or otherwise alter the
high-voltage circuitry or the CRT enclosure. X-ray emissions generated within
this product have been sufficiently shielded.

Handheld and Benchtop Instruments Basic Service vii
Preventing Electrostatic Discharge
CAUTION. Static discharge can damage internal semiconductor components.
Follow the guidelines listed below to avoid product damage.
When performing service that requires internal access to an instrument, adhere to
the following precautions to avoid damaging internal modules or their compo-
nents:
Avoid handling modules or components in areas that have floors or work
surfaces capable of generating a static charge.
Spray carpeted work areas with a solution of equal parts of water and fabric
softener.
Wear clothing made from materials that do not accumulate static charges.
Avoid Wool (and some artificial fibers) which build up static charges readily;
wear cotton which conducts electricity and resists static accumulation.
Minimize the handling of static-sensitive devices.
Transport and store static-sensitive devices in their protected containers or on
a metal rail. Label any package that contains static-sensitive parts.
Service instruments and modules at grounded, static-free work stations.
Do not allow devices capable of generating a static charge on a work station
surface.
Wear a grounding strap while working with static-sensitive devices.
Handle circuit boards by their edges, if possible.
Do not slide static-sensitive components over any surface.
Do not use high-velocity compressed air to clean or dry components or
modules.

Preventing Electrostatic Discharge
viii Handheld and Benchtop Instruments Basic Service

Handheld and Benchtop Instruments Basic Service ix
Preface
This manual contains service information for a wide range of handheld and
benchtop products. Each section covers a product or related series of products
and includes the following information:
A product description that details instrument functions, capabilities, and
recommended uses
A front panel illustration
A set of electrical, mechanical, environmental, and physical specifications
A performance verification procedure to ensure the instrument meets
specifications
An adjustment procedure to return the instrument to factory calibration (not
included for all instruments)
The information contained in this manual is current at the date of publication and
is typical or suggested, not guaranteed. Since manual updates occur at approxi-
mately six month intervals, information may be incomplete or missing in some
versions.
Some instruments have optional service information available under separate
cover. This manual does not duplicate information from optional service
manuals. Refer to the optional accessories list in your user manual for Tektronix
part numbers of optional service manuals. A list of Handheld and Benchtop
instruments manuals can also be found on Page i.
NOTE. This manual provides the necessary service information to verify that
your instrument is working properly. Should you have service-related questions
not covered in either this manual or in an optional service manual, please
contact your Tektronix Service Center for additional information.
For product warranty information, refer to the user manual supplied with your
instrument.

Preface
xHandheld and Benchtop Instruments Basic Service
Contacting Tektronix
Product
Support For application-oriented questions about a Tektronix measure- ment 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:
[email protected]
For product support outside of North America, contact your
local Tektronix distributor or sales office.
Service
Support Contact your local Tektronix distributor or sales office. Or visit our web site for a listing of worldwide service locations.
http://www.tek.com
For other
information In North America: 1-800-TEK-WIDE (1-800-835-9433)
An operator will direct your call.
To write us Tektronix, Inc.
P.O. Box 1000
Wilsonville, OR 97070-1000

Instructions Manual
DCM300 and DCM320
Digital Clamp Multimeters
070-9847-00

Handheld and Benchtop Instruments Basic Service i
Table of Contents
DCM300 and DCM320 Digital Clamp Multimeters 1. . . . . . . . . . . . . .
Specifications 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Performance Verification 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test Equipment 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Set Up 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Verification Procedure 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test Records 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adjustment Procedures 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List of Adjustments 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test Equipment 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preparation for Adjustment 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adjustment Procedure 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table of Contents
ii Handheld and Benchtop Instruments Basic Service

Handheld and Benchtop Instruments Basic Service 1
DCM300 and DCM320 Digital Clamp Multimeters
The DCM300 and DCM320 Digital Clamp Multimeters measure AC current,
AC voltage, and resistance/continuity. The meters use a current transformer to
measure current without opening the circuit.
The meters automatically select the correct measurement range and have a 4000
count resolution. (The maximum reading is 3999.)
The DCM320 meter provides true RMS readings for both AC volts and AC
current.
Figure 1: DCM300 Digital Clamp Multimeter

DCM300 and DCM320 Specifications
2Handheld and Benchtop Instruments Basic Service
Specifications
The characteristics listed in this section apply under the following conditions:
HThe instrument operates in a 0_to 45_C ambient environment unless
otherwise noted.
HThe instrument warms up for at least 20 minutes.
NOTE. All specifications are warranted unless marked “typical.” Typical
characteristics are not guaranteed but are provided for the convenience of the
user.
Table 1: Electrical Characteristics
Characteristic Description
AC Voltage, Auto Ranging (nominal Input Impedance: 10 M, <100 pF)
Ranges 600 V and 400 V
VoltageRating 600 VRMS CAT II
Resolution
400 V Range 0.1 V
600 V Range 1 V
Accuracy 40 to 500 Hz: ±(1.2% of reading + 5 digits)
Crest Factor (DCM 320 only) 1.4 to 2.0, add 0.6% to accuracy
2.0 to 2.5, add 2.0% to accuracy
AC Current, Auto Ranging
Ranges 600A and 400A
OverloadProtection 800 A
UninsulatedWire Voltage Rating 600 VRMS CAT II
Resolution
400 A Range 0.1 A
600 A Range 1 A
Accuracy 50 to 60 Hz
400A Range ±(1.9% of reading + 5 digits)
600 A Range ±(2.9% of reading + 5 digits)
Crest Factor (DCM 320 only) 1.4 to 2.0, add 1.0% to accuracy
2.0 to 2.5, add 2.5% to accuracy

DCM300 and DCM320 Specifications
Handheld and Benchtop Instruments Basic Service 3
Table 1: Electrical Characteristics (Cont.)
Characteristic Description
Resistance, Auto ranging (meter beeps if resistance is <100 W.)
Ranges 4 kWand 40 kW
OverloadProtection 600 VRMS
Resolution
4 kWRange 1 W
40 kWRange 10 W
Accuracy ±(2.0% of reading + 9 digits)
Maximum Open Circuit Voltage 1 V
Table 2: General Specifications
Characteristic Description
Auto Power Off Approximately30 minutes
Battery 9 V, NEDA1604, IEC6F22, JIS 006P
BatteryLife 200 hours (alkaline)
MaximumConductor Size 40 mm
Table 3: Certifications and Compliances
Certifications
C
anadian Standards Association certified to Standard
C
SA 1
0
1
0
.1, Standard
UL3111-1 for Electrical and Electronic Measuring and Testing Equipment, and
IC00--03 m - m
3- T m
IEC1010-2-032particular requirements for hand-held currentclamps for electrical
measurementand test.
OvervoltageCategory Category: Examples of Products in this Category:
CAT III Distribution-levelmains, fixed installation
CAT II Local-levelmains, appliances, portable equipment
CAT I Signal levels in special equipment or parts of equipment,
telecommunications,electronics
PollutionDegree 2 Do not operate in environments where conductive pollutants may be present.

DCM300 and DCM320 Specifications
4Handheld and Benchtop Instruments Basic Service
Table 4: Environmental Characteristics
Characteristic Description
Temperature
Operating 0_to 45°C (32_to 113°F), <75% relative humidity
Nonoperating –20_to +60°C (–4_to 140°F), <80% relative humidity
TemperatureCoefficient 0.2% (specified accuracy) per _C at <18_C (64_F) or >28_C (82_F)
MaximumAltitude(Operating) 2,200 m (7,218 ft.)

DCM300 and DCM320 Performance Verification
Handheld and Benchtop Instruments Basic Service 5
Performance Verification
This section contains procedures to verify that the DCM300 and DCM320
Digital Clamp Multimeters perform as warranted. If an instrument fails any of
the checks, it needs adjustment and or repair.
The performance verification procedures provide a valid confirmation of
instrument electrical characteristics and function under the following conditions:
HThe instrument operates in an 18_to 28_C ambient environment with a
relative humidity of less than 75%.
HThe instrument warms up for 20 minutes.
HThe instrument remains fully assembled (do not remove the bottom cover).
The DCM300 and DCM320 performance verification consists of the checks
listed in Table 5.
Table 5: Performance Verification Checks
AC Current Check
AC VoltageCheck
Resistanceand Continuity Check
Test Equipment
The performance verification procedures use external traceable test equipment to
directly check warranted characteristics. If you substitute equipment, always
choose instruments that meet or exceed the minimum requirements specified in
Table 6.
Alternative test equipment must meet or exceed the intended minimum
requirements. If you substitute equipment, you may need to modify the
performance verification procedures.
NOTE. Before beginning the performance verification procedures, warm up the
test equipment according to the manufacturer’s recommendations.