Tektronix A621 User manual

Instructions
A621
1000 Amp AC Current Probe
070-8882-02

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.
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Warranty 2
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. Parts, modules and replacement products used by
Tektronix for warranty work may be new or reconditioned to like new performance. All
replaced parts, modules and products become the property of Tektronix.
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; c) to repair any
damage or malfunction caused by the use of non-Tektronix 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 WITH RESPECT TO THE
PRODUCT IN LIEU OF ANY OTHER WARRANTIES, EXPRESS 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.
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Contacting Tektronix
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*
Service
support
1-800-833-9200, select option 2*
Technical
support
www.tektronix.com/support
1-800-833-9200, select option 3*
6:00 a.m. -- 5:00 p.m. Pacific Standard 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.
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A621 Ins t ruc ti ons
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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. Connect the probe output to the
measurement instrument before connecting the probe to the circuit
under test. Disconnect the probe input and the probe ground from the
circuit under test before disconnecting the probe from the measure-
ment instrument.
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 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 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.
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General Safety Summary
Safety Terms and Symbols
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. These symbols may appear on the product:
CAUTION
Refer to Manual
Double
Insulated
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Product Description
The Tektronix A621 current probe enables the display of current
waveforms up to 1000 amps RMS on Tektronix TDS, TAS, or
general purpose oscilloscopes. The A621 is especially useful where
the display and measurement of distorted current waveforms and
harmonics is required. The A621 is also compatible with DMMs by
using the BNC-to-banana plug adapter (recommended accessory, see
page 17 for more information).
Current Flow Symbol
This arrow shows the probe’s polarity convention for measuring
current flowing from positive to negative.
1000
100
10
Range Switch
Slide to select the measurement range of theprobe-
10/100/1000 A.
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A621 Ins t ruc ti ons
Operating Basics
WARNING. Do not clamp the probe onto circuits with voltages greater
than 600 VAC. Personal injury or damage to the probe may result.
Always connect the probe to the instrument before clamping onto the
circuit under test.
1.
Connect the probe BNC connector to the oscilloscope input. Start
by setting the oscilloscope channel vertical coupling to AC volts,
the vertical deflection to 0.1 V/div, and the probe to 1 mV/A.
2. Connect the probe to the circuit by opening the jaws and
clamping around the conductor. See Figure 1. Note: Clamping
around both the “hot” and neutral wires may give you a zero
reading.
To load
From source
Figure 1: Connecting the A621
(Remember to unclamp the probe from the conductor before
disconnecting it from your meter or instrument.)
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Operating Basics
3. Adjust the probe range and scope channel as necessary to get a
clear view of the signal.
The current drawn by some devices will look much different than
that of others. While the RMS current may be low, the momentary
peaks may be quite high. Figure 2 shows the difference between the
line current drawn by a resistive load and a motor controller.
Resistive Load
Motor Controller
Figure 2: Typical Current Waveforms
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Operating Basics
If you are using the A621 with a multimeter, use the BNC-to-banana
adapter (recommended accessory) to connect the probe. Connect the
black lead to the meter COM, and the red lead to the VΩinput. Set
the meter to the AC Volts position.
To increase the measurement sensitivity of the A621, loop additional
turns of the wire under test through the jaws. See Figure 3. The
sensitivity of the A621 will be multiplied times the number of loops
in the jaws. For example: 10 mV/A X 4 turns = 40 mV/A.
Figure 3: Increasing the A621 Sensitivity
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Specifications
These characteristics apply to an A621 probe installed on a Tektronix
TDS320 oscilloscope. The oscilloscope must be warmed up for at
least 20 minutes and be in an environment within the limits in
Table 3.
Table 1: Electrical Characteristics
Output
1/10/100 mV/A
Accuracy
±2% at 1 mV/A and 10 mV/A
±3% at 100 mV/A
Maximum Working Current
2000 APEAK at 1 mV/A
1000 ARMS at 1 mV/A
200 APEAK at 10 mV/A
20 APEAK at 100 mV/A
Maximum Working Voltage
600 V CAT III
Frequency Range
5 Hz to 50 kHz
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A621 Ins t ruc ti ons
Specifications
Typical Response Curves
1 mV/A Range
1.00
Accuracy vs.Frequency
0.00
--1.00
--2.00
--3.00
--4.00
--5.00
10
1 mV/A Range
5.00
0.00
--5.00
--10.00
--15.00
--20.00
--25.00
--30.00
--35.00
--40.00
10
100 1000 10,000
Frequency (Hz)
Phase Shift vs. Frequency
100 1000 10,000
Frequency (Hz)
100,000
100,000
@ 10 A
@ 50 A
Accuracy In %
@ 10 A
@ 50 A
Phase In Degrees
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Specifications
10 mV/A Range
5.00
Accuracy vs.Frequency
0.00
--5.00
--10.00
--15.00
--20.00
--25.00
--30.00
10 100 1000 10,000
Frequency (Hz)
100,000
10 mV/A Range
10.00
0.00
--10.00
--20.00
--30.00
--40.00
--50.00
--60.00
--70.00
10
Phase Shift vs. Frequency
100 1000 10,000
Frequency (Hz)
100,000
@ 1A
@ 5A
Accuracy In %
@ 1A
@ 5A
Phase In Degrees
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A621 Ins t ruc ti ons
Specifications
100 mV/A Range
5.00
0.00
--5.00
--10.00
--15.00
--20.00
--25.00
--30.00
--35.00
--40.00
--45.00
10
Accuracy vs.Frequency
100 1000 10,000
Frequency (Hz)
100,000
100 mV/A Range
50.00
40.00
30.00
20.00
10.00
0.00
--10.00
--20.00
--30.00
--40.00
--50.00
Phase Shift vs. Frequency
100 1000 10,000
Frequency (Hz)
100,000
@ 0.1A
@ 0.5A
@ 0.1A
@ 0.5A
Phase In Degrees
Accuracy In %
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Specifications
Table 2: Physical Characteristics
Dimensions
206 mm x 48 mm x 105 mm
(8.11 x 1.89 x 4.13 inches)
Maximum Conductor Size
54 mm (2.13 inches)
Cable Length
1.5 m (5 feet)
Weight
650 g (1.43 lb)
Figure 4: Physical dimensions
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A621 Ins t ruc ti ons
Specifications
Table 3: Environmental Characteristics
Temperature
Working
Storage
0°C to +50°C
(+32°to +122°F)
--20°C to +80°C
(--4°to +176°F)
Humidity
0°C to 40°C, 95%humidity
40°C to 50°C, 45%humidity
Table 4: Certifications and compliances
EC Declaration of
Conformity
Compliance was demonstrated to the following specification as
listed in the Official Journal of the European Communities:
Low Voltage Directive 73/23/EEC, as amended by93/68/EEC
EN 61010-1/A2:1995
Safety requirements for electrical equipment for
measurement, control, and laboratory use.
EN 61010-2-032:1995
Particular requirements for hand-held current clamps for
electrical measurement and test equipment.
Installation
(Overvoltage)
Category
Terminals on this product may have different installation
(overvoltage) category designations. The installation categories
are:
CAT III Distribution-level mains (usually permanently
connected). Equipment at this level is typically in a
fixed industriallocation.
CAT II Local-level mains (wall sockets). Equipment at this
level includes appliances, portable tools, and similar
products. Equipment is usually cord-connected.
CAT I Secondary (signal level) or battery operated circuits of
electronic equipment.
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11
Specifications
Table 4: Certifications and compliances (cont.)
Pollution Degree 2
Do not operate in environments where conductive pollutants may
be present.
U.S. Nationally
UL3111-1, First Edition & UL3111-2-032, First Edition
Recognized Testing
CSA C22.2 No. 1010.1-92 & CAN/CSA C22.2 No. 1010.2.031-94
LaboratoryListing
IEC61010-1/A2
EN 61010-2-032
Pollution Degree 2
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A621 Ins t ruc ti ons
Performance Verification
This procedure verifies that the A621 performs as specified. It can
also be an acceptance check. There are no A621 adjustments. This
procedure is valid when:
• The system is operated in an environment that conforms to the
A621 environmental specifications (0。C to 50。C unless
otherwise stated).
• The oscilloscope is set to DC coupling, normal triggering.
The performance verification procedure requires the test equipment
in Table 5, or its equivalent. If different equipment is substituted,
control settings or test equipment setup may need to be altered.
The performance verification consists of an accuracy check of the
probe ranges.
Warm up the test equipment at least 20 minutes to stabilize it before
performing the checks.
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Performance Verification
Table 5: Test Equipment Required for Performance Verification
Item
Minimum Requirements
Recommended Example
Oscilloscope
1 MΩinput, general
purpose oscilloscope
Tektronix
TAS/TDS series
Signal Generator
60 Hz Sine Wave, ≥50 mARMS
into <1 Ω
Tektronix FG 501A1,
FG 5041or equivalent
Multimeter
≥0.5 A max. input current,
accuracy ≤0.6% of reading on
AC Current measurement at
60 Hz
Tektronix DM 504A1
or equivalent
Current Loop, 100 turn
100 turns coated wire,
20 AWG (≈0.9 mm),
loop diameter 7.5 cm (3 in),
alligator clips onends
See procedure
18 inch banana jack-to-banana jack patch cords, three
required
Tektronix part numbers:
012-0031-00
012-0039-00
1
Requires Tektronix TM 500 Series or Tektronix TM 5000 Series Power Module
100 Turn Current Loop
CAUTION. It is not recommended that a coil with greater than 100
turns be made. Magnetic fields are produced that may cause a
malfunction in heart pacemakers, or damage to sensitive equipment.
Coil currents in excess of 0.2 Amperes are not recommended.
For the accuracy check you will need a simple current loop. Wind
100 turns of 20 AWG (≈0.9m diameter) coated wire around a
cylindrical form approximately 7.5 cm (3 inches) in diameter.
NOTE. Be sure the current loop has exactly 100 turns. A significant
error will result for each extra or missing turn.
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A621 Ins t ruc ti ons
Performance Verification
AC Accuracy Check
1. Connect the 100 turn current loop, the multimeter current inputs,
and the signal generator output in series, using the patch cords
and adapter. Set the multimeter to display ACRMS current. See
Figure 5.
Multimeter
Signal
Generator
Oscilloscope
100 Turn coil
A621
Figure 5: Setup for Maximum Input Current and Accuracy Checks
2. Adjust the signal generator output to between 49 mARMS and
51 mARMS as measured on the multimeter.
3. Connect the A621 to the oscilloscope, and make the following
oscilloscope settings:
• time base to 5 mS / div.
•
vertical deflection to 500 mV / div.
• coupling to DC
4. Set the A621 sensitivity switch to 100 mV / A and center the
trace on the oscilloscope screen.
5. Clamp the A621 around the 100 turn current loop.
6. If necessary, readjust the signal generator output to read between
49 mARMS and 51 mARMS on the multimeter.
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