Tektronix P6021 User manual

Instruction Manual
P6021
60 MHz Current Probe
070-0947-05
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.
www.tektronix.com

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.
Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
LUBRIPLATE is a registered trademark of the Fiske Brothers Refining Co.
POSIDRIV is a registered trademark of the Philips Screw Co.

WARRANTY
Tektronix warrants that this product will be free from defects in materials and workmanship for a period of one (1)
year from the date of shipment. If any such product proves defective during this warranty period, Tektronix, 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 Tektronix, with
shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a
location within the country in which the Tektronix 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. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage
resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product;
b) to repair damage resulting from improper use or connection to incompatible equipment; or c) 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 WITH RESPECT TO THIS PRODUCT IN LIEU OF
ANY OTHER WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX AND ITS VENDORS
DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE. TEKTRONIX’ RESPONSIBILITY TO REPAIR 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.

P6021 Instruction Manual i
Table of Contents
General Safety Summary iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Safety Summary v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contacting Tektronix vi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operator Information 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Description 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating Considerations 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Information 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Warranted Characteristics 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Typical Characteristics 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Description 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Performance Verification 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adjustment Procedures 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replaceable Electrical Parts 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Ordering Information 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the Replaceable Electrical Parts List 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replaceable Mechanical Parts 37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Ordering Information 37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the Replaceable Mechanical Parts List 37. . . . . . . . . . . . . . . . . . . . . . . . . . .
Index 43. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table of Contents
ii P6021 Instruction Manual
List of Figures
Figure 1: The P6021 Probe and Termination 2. . . . . . . . . . . . . . . . . . . .
Figure 2: Insertion Impedance of the P6021 5. . . . . . . . . . . . . . . . . . . . .
Figure 3: Probe and Termination Input Current vs.
Frequency Derating 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 4: Typical P6021 Phase Response 11. . . . . . . . . . . . . . . . . . . . . . .
Figure 5: P6021 Schematic Diagram 13. . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6: Connecting the Probe to the Calibration Fixture 18. . . . . . . .
Figure 7: Location of Probe Adjustments 19. . . . . . . . . . . . . . . . . . . . . . .
Figure 8: Location of Termination Adjustments 20. . . . . . . . . . . . . . . . .
Figure 9: Disassembling the Probe 27. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 10: P6021 Probe Component Location 35. . . . . . . . . . . . . . . . . . .
Figure 11: P6021 Termination Component Location 35. . . . . . . . . . . . . .
Figure 12: P6021 Exploded View 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List of Tables
Table 1: Warranted Electrical Characteristics 7. . . . . . . . . . . . . . . . . .
Table 2: Warranted Environmental Characteristics 8. . . . . . . . . . . . . .
Table 3: Maximum Ratings 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 4: Certifications and Compliances 9. . . . . . . . . . . . . . . . . . . . . . .
Table 5: Electrical Characteristics 10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 6: Mechanical Characteristics 11. . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 7: Equipment List 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P6021 Instruction Manual iii
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.
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.
Connect the ground lead of the probe to earth ground only.
Do not apply a potential to any terminal, including the common terminal, that
exceeds the maximum rating of that terminal.
Do Not Operate Without Covers. Do not operate this product with covers or panels
removed.
Avoid Exposed Circuitry. Do not touch exposed connections and components
when power is present.
Do Not Operate With SuspectedFailures. If you suspect there is damage to this
product, have it inspected by qualified service personnel.
Do Not Operate in Wet/DampConditions.
Do Not Operate in an Explosive Atmosphere.
Keep Product Surfaces Clean and Dry.
To Avoid Fire or
Personal Injury

General Safety Summary
iv P6021 Instruction Manual
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 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 Double
Insulated ProtectiveGround
(Earth) Terminal
Symbols and Terms

P6021 Instruction Manual v
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.
To avoid electric shock, do not touch exposed connections.

Contacting Tektronix
vi P6021 Instruction Manual
ContactingTektronix
Phone [phone]*
Address Tektronix, Inc.
Department or name (if known)
14200 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
Web site www.tektronix.com
Sales support 1-800-833-9200, select option 1*
Servicesupport 1-800-833-9200, select option 2*
Technical support Email: [email protected]
1-800-833-9200, select option 3*
1-503-627-2400
6:00 a.m. – 5:00 p.m. Pacific time
*This phone number is toll free in North America. After office hours, please leave a
voice mail message.
Outside North America, contact a Tektronix sales office or distributor; see the
Tektronix web site for a list of offices.

P6021 Instruction Manual 1
Operator Information
Thank you for choosing a Tektronix current probe. This manual describes the
P6021 current probe with passive termination and provides information about
making measurements with the probe.
Description
The P6021 current probe converts an alternating current waveform to a voltage
that can be displayed and measured on an oscilloscope display. The probe
provides accurate current measurements over a wide range of frequencies and
allows you to measure current without breaking the circuit.
The P6021 probe is compatible with general purpose oscilloscopes having a
1M W input impedance. The P6021 probe comes with a passive termination that
matches oscilloscope and probe impedance, optimizes the probe performance,
and provides two sensitivity settings.
In the standard configuration, the P6021 probe comes with a 5-foot cable and
termination. The following option is also available.
Option 03. 9-foot cable with termination
Installation
This section describes both attaching the probe to an oscilloscope and using the
standard accessories with the probe.
To ensure the best performance from your probe and oscilloscope measurement
system, check that the probe and oscilloscope are appropriately matched. The
oscilloscope inputs should use BNC connectors and have an impedance of
1M W .
Figure 1 shows the probe and various parts referred to in this manual.

Operator Information
2P6021 Instruction Manual
P6021 Probe
Termination
6" Ground Lead
Figure 1: The P6021 Probe and termination
Attach the probe to the termination as shown in Figure 1.
An alligator-style ground clip is supplied to improve EMI rejection at high
frequencies (2 MHz and above). Snap the ground lead to the probe transformer
post and attach the alligator clip directly to RF ground. This will reduce ringing
and help bypass capacitively-coupled RF currents that can flow into the probe
cable.
WARNING. To avoid injury or equipment damage, remove power from an
uninsulated wire before clamping the current probe around it. When the probe
slides are open, the exposed ferrite core pieces are not insulated. Also, never
disconnect the probe from the termination when the probe is connected to a live
conductor.
To avoid damaging the probe, do not disconnect the probe termination and leave
the P6021 clamped around the conductor when measuring high currents.
Leaving the probe cable unterminated can cause a high voltage to develop in the
secondary winding, which may damage the current probe transformer.
Attaching the Probe and
Termination to an
Oscilloscope

Operator Information
P6021 Instruction Manual 3
Your P6021 is shipped with the following accessories:
H This instruction manual — Read these instructions to familiarize yourself
with the features, specifications, and operation of the P6021 current probe.
H 6-inch ground lead — Use the 6-inch ground lead to ground the shield
around the probe transformer at the probe end of the cable. This allows you
to move the ground connection closer to the circuit that you are measuring,
thereby improving high frequency response. The ground lead clips onto the
ground connector on the bottom of the probe as shown.
Please refer to the parts list in the section entitled Replaceable Mechanical Parts
for part numbers.
Your P6021 may be used with the following optional accessory:
H CT-4 Current Probe — The CT-4 is a robust clip-on transformer that
extends the current range of the P6021 up to 1000 amps (provided the
amp-second rating is not exceeded). The CT-4 has receptacles for current
probes in either 20:1 or 1000:1 step-down ratios.
Using the Standard
Accessories
Optional Accessories

Operator Information
4P6021 Instruction Manual
Operating Considerations
The information in this section will help you make effective use of your P6021
probe.
H Sensitivity Control — The P6021 termination has a control that allows you
to select probe sensitivity. The switch has two positions: 2 mA/mV and
10 mA/mV. When the control is in the 2 mA/mV position, the oscilloscope
displays 1 mV for every 2 mA of current in the circuit under test. When the
control is in the 10 mA/mV position, the oscilloscope displays 1 mV for
every 10 mA of current in the circuit under test.
You can set vertical scale on the oscilloscope to any scale factor, as
determined by the signal amplitude. To calculate the overall vertical scale
factor for the oscilloscope, probe, and termination, multiply the termination
sensitivity control setting by the vertical scale factor of the oscilloscope. For
example, if the termination control is set to the 10 mA/mV position and the
oscilloscope to a vertical scale of 20 mV/division, the overall scale factor is
10 X 20, or 200 mA/division.
H Probe Slide Switch — The slide switch on the probe has three positions:
open, closed, and locked. Use your thumb to move the probe slide switch.
The switch is spring loaded so that it automatically moves from the open to
closed positions.
To Use the Probe:
a. Pull the slide switch toward you, and hold the switch in position.
b. Place the conductor-under-test inside the exposed transformer core. The
arrow on the transformer end of the probe indicates conventional current
flow. If you place the probe on the conductor so that the arrow on the
probe matches conventional current flow through the conductor,
orientation of the displayed waveform will be correct.
c. Release the switch, allowing the probe to close.
d. Lock the slide switch. To lock the switch, push it firmly toward the
transformer (the switch will move only about 1/8th inch). Locking the
switch assures maximum contact between the two halves of the
transformer secondary. The conductor now becomes the primary of the
transformer. (When measuring current, always check that the probe slide
switch is moved completely forward into the locked position.)
WARNING. To prevent shock when measuring uninsulated conductors, keep your
hands and fingers behind the ridge on the probe head.
Sensitivity
control
Probe
slide switch
Open
Closed
Locked
Ridge
Features and Controls

Operator Information
P6021 Instruction Manual 5
When you insert a conductor into the probe, you add impedance to the circuit
you are measuring. This additional impedance affects signals; this is particularly
important if you are measuring fast rise times. Figure 2 illustrates the equivalent
circuit with the additional impedance introduced by the P6021.
.004 W
1.7 nH2.8 m H
Figure 2: Insertion Impedance of the P6021
To minimize the loading effect of the probe, clamp it at the low or ground end of
a component lead when possible. This method also minimizes noise or stray
signal interference.
You can increase the current sensitivity of the probe by increasing the number of
times a conductor passes through it. For example, if the conductor loops through
the probe twice (a two-turn primary winding), the secondary current is doubled.
For example, suppose you set the termination sensitivity to 2 mA/mV and the
oscilloscope vertical scale to 10 mV/division. Ordinarily, this would result in the
equivalent of 2 X 10, or 20 mA/division. However, if the conductor is looped
through the probe twice, the vertical scale is divided by two, resulting in the
equivalent of 10 mA/division.
Looping the conductor twice effectively doubles vertical sensitivity; however,
impedance from the probe winding is also reflected into the circuit being
measured. This impedance is proportional to the square of the number of loops.
This additional impedance affects signals; this impedance is particularly
important when you are measuring high-frequency current waveforms or
waveforms with fast rise times.
Insertion Impedance
Minimizing Loading Effect
Increasing Probe
Sensitivity

Operator Information
6P6021 Instruction Manual
The P6021 is shielded to minimize the effect of external magnetic fields.
However, strong fields can interfere with the current signal being measured. If
you suspect that an external field is interfering with your measurement, remove
the probe from the conductor, but keep it in the same location as when you made
the suspect measurement. If a signal still appears on the oscilloscope, try to
measure the conductor current at a point farther from the location of the magnetic
field.
If you must measure current in the presence of a strong magnetic field, you can
minimize its interference by using two current probes and a differential-input
oscilloscope. To do so, follow these steps.
1. Connect the probes (with termination) to the positive and negative inputs of
the oscilloscope.
2. Clamp one probe around the conductor whose current you want to measure.
3. Place the other probe as close as possible to the first. Ensure that its slide
switch is completely closed, without a conductor inside it.
4. Set the oscilloscope to subtract the component of the signal that is common
to both probes.
5. Adjust the positions of the probes for best results. It may be difficult to
eliminate the undesirable signal completely, due to differences between the
probes or their terminations.
The flat-top response of any AC current probe displays a certain amount of
droop. This is caused by probe inductance loading the source impedance, causing
an L/R exponential decay. For short pulse widths, the response looks nearly flat.
The amount of droop can be calculated from the following relationship:
% Droop = 200 ( p ) T f
where:
T=pulse duration in microseconds
f=lower 3 dB frequency of probe in Hertz
For example, to calculate the percent droop of a 100 m s pulse measured with a
P6021 probe:
In the 10 mA/mV position, f=120 Hz
% Droop = 200 ( p ) T f
= 200 ( p ) (100*10–6) (120)
= 0.075%
Probe Shielding
Droop

P6021 Instruction Manual 7
Service Information
Warranted Characteristics
This section lists the various warranted characteristics that describe the P6021
Current Probe. Included are warranted electrical and environmental characteris-
tics.
Warranted characteristics are described in terms of quantifiable performance
limits which are warranted.
The electrical characteristics listed in Table 1 apply under the following
conditions:
H The probe and instrument must be in an environment whose limits are
described in Table 2.
Table 1: Warranted electrical characteristics
Characteristic Information
Sensitivity 2 mA or 10 mA for each mV at oscilloscope input,
selectedbyterminationsensitivitycontrol
MidbandAccuracy ±3% at 10 kHz to 30 kHz
SystemBandwidth
(with BW>200 MHz oscilloscope)
2 mA/mV 450 Hz to 60 MHz
10 mA/mV 120 Hz to 60 MHz
Probe Rise Time ≤5.8 ns
StepResponse Becausetheoscilloscopeinput capacitance becomes
a part of the termination network, the step response
will vary with different oscilloscopes
Aberrations(probe and termination
at either sensitivity setting.) ≤10% peak-to-peak within50 ns of step; ≤2% peak-to-peakthereafter

Service Information
8P6021 Instruction Manual
Table 2: Warranted environmental characteristics
Characteristic Information
Temperaturerange
Operating –0 _ C to +50 _ C (+32 _ F to +122 _ F)
Nonoperating –40 _ C to +65 _ C (–40 _ F to +149 _ F)
Altitude
Operating To 2,000 m (6,561 ft), <300 V CAT I
To 4,572 m (15,000 ft), <150 V, CAT I
Nonoperating To 15,240 m (50,000 ft)
Table 3: Maximum ratings
Characteristic Information
Maximum Continuous (CW) Current Refer to Figure 3 for frequency derating curves
2 mA/mV 5A
p-p sine wave between 1.2 kHz and 5 MHz
10 mA/mV 15 Ap-p sine wave between 300 Hz and 5 MHz
MaximumPulse Current 250 A peak, not to exceed 500(A · m s) or 5 ARMS. An
(A · s) product greater than 500(A · m s)reduces
probe output to zero due to core saturation
MaximumWorking
Input Voltage
(uninsulatedconductors)
300 VAC or VDC, CAT I, and 600 Vpk limited to
<10 ms and <25% duty factor.

Service Information
P6021 Instruction Manual 9
100 MHz10 MHz1 MHz1 kHz100 Hz10 Hz
FREQUENCY
1A
0.1A
PĆP
AMPS
10 A
20 A
100 A
10mA/mV
2 mA/mV
Figure 3: Probe and termination input current vs. frequency derating
Table 4: Certifications and compliances
EC Declaration of Conformity – Low Voltage
Compliance was demonstrated to the following specifications as listed in the
Official Journal of the European Communities:
Low Voltage Directive 73/23/EEC,as amended by 93/68/EEC
EN61010-1/A2 Part 1: General Requirements
Safetyrequirementsfor electrical equipment for
measurement,control, and laboratory test
EN61010-2-032:1995 Part2-032:
Particularrequirements for hand-held current clamps
forelectricalmeasurements and test
ListedUL1244, Third Edition Electrical and electronic measuring and test
equipment

Service Information
10 P6021 Instruction Manual
Table 4: Certifications and compliances (Cont.)
InstallationCategoryDescriptions
Terminals on this product may have differentinstallation category
designations.The installation categories are:
CAT III Distribution-levelmains (usuallypermanently
connected). Equipment at this level is typically in a
fixedindustrial location
CAT II Local-level mains (wall sockets). Equipment at this
level includes appliances, portable tools, and similar
products.Equipment is usuallycord-connected
CAT I Secondary (signal level) or battery operated circuits
ofelectronic equipment
PollutionDegree2 Do not operate in environments where conductive
pollutantsmaybe present.
Typical Characteristics
This section lists the various typical characteristics that describe the P6021
Current Probe. Included are typical electrical and mechanical characteristics.
Typical characteristics are described in terms of typical or average performance.
Typical characteristics are not warranted.
Table 5: Electrical characteristics
Characteristic Information
Tilt
2 mA/mV 2.8% or less within 10 m s of step
10 mA/mV 7.5% or less within 100 m s of step
Maximum DCsaturation 0.5 A
SignalDelay
5-foot probewith termination Approximately9 ns
9-footprobewith termination Approximately 15.8 ns
InsertionImpedance 0.03 W or less at 1 MHz, increasing to 1.0 W or less
at 60 MHz