Keysight 1143A User manual

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Keysight 1143A
Probe Offset Control and
Power Module
User’s Guide

2 1143A Probe Offset Control and Power Module User’s Guide
Notices
© Keysight Technologies, 2000-2014, 2017
No part of this manual may be reproduced in
any form or by any means (including elec-
tronic storage and retrieval or translation into
a foreign language) without prior agreement
and written consent from Keysight Technolo-
gies, Inc. as governed by United States and
international copyright laws.
Manual Part Number
01143-97003
May 2017
Printed in Malaysia
Published by:
Keysight Technologies
1400 Fountaingrove Parkway
Santa Rosa, CA, 95403
Warranty
The material contained in this document is
provided “as is,” and is subject to being
changed, without notice, in future editions.
Further, to the maximum extent permitted
by applicable law, Keysight disclaims all
warranties, either express or implied, with
regard to this manual and any information
contained herein, including but not limited
to the implied warranties of merchantability
and fitness for a particular purpose. Key-
sight shall not be liable for errors or for inci-
dental or consequential damages in
connection with the furnishing, use, or per-
formance of this document or of any infor-
mation contained herein. Should Keysight
and the user have a separate written agree-
ment with warranty terms covering the
material in this document that conflict with
these terms, the warranty terms in the sepa-
rate agreement shall control.
Technology Licenses
The hardware and/or software described in
this document are furnished under a license
and may be used or copied only in accor-
dance with the terms of such license.
U.S. Government Rights
The Software is "commercial computer
software," as defined by Federal Acqui-
sition Regulation ("FAR") 2.101. Pursu-
ant to FAR 12.212 and 27.405-3 and
Department of Defense FAR Supplement
("DFARS") 227.7202, the U.S. govern-
ment acquires commercial computer
software under the same terms by which
the software is customarily provided to
the public. Accordingly, Keysight pro-
vides the Software to U.S. government
customers under its standard commer-
cial license, which is embodied in its
End User License Agreement (EULA), a
copy of which can be found at
http://www.key-
sight.com/find/sweula. The license
set forth in the EULA represents the
exclusive authority by which the U.S.
government may use, modify, distribute,
or disclose the Software. The EULA and
the license set forth therein, does not
require or permit, among other things,
that Keysight: (1) Furnish technical
information related to commercial com-
puter software or commercial computer
software documentation that is not cus-
tomarily provided to the public; or (2)
Relinquish to, or otherwise provide, the
government rights in excess of these
rights customarily provided to the public
to use, modify, reproduce, release, per-
form, display, or disclose commercial
computer software or commercial com-
puter software documentation. No addi-
tional government requirements beyond
those set forth in the EULA shall apply,
except to the extent that those terms,
rights, or licenses are explicitly required
from all providers of commercial com-
puter software pursuant to the FAR and
the DFARS and are set forth specifically
in writing elsewhere in the EULA. Key-
sight shall be under no obligation to
update, revise or otherwise modify the
Software. With respect to any technical
data as defined by FAR 2.101, pursuant
to FAR 12.211 and 27.404.2 and DFARS
227.7102, the U.S. government acquires
no greater than Limited Rights as
defined in FAR 27.401 or DFAR
227.7103-5 (c), as applicable in any
technical data.
Safety Notices
CAUTION
A CAUTION notice denotes a hazard. It
calls attention to an operating proce-
dure, practice, or the like that, if not
correctly performed or adhered to, could
result in damage to the product or loss
of important data. Do not proceed
beyond a CAUTION notice until the indi-
cated conditions are fully understood
and met.
WARNING
A WARNING notice denotes a hazard. It
calls attention to an operating proce-
dure, practice, or the like that, if not
correctly performed or adhered to,
could result in personal injury or death.
Do not proceed beyond a WARNING
notice until the indicated conditions
are fully understood and met.

1143A Probe Offset Control and Power Module User’s Guide 3
Contents
Contents
1 Using the 1143A
Safety Information / 8
Using the 1143A / 11
Remote Control / 14
Characteristics / 16
Testing Performance / 19
Contacting Keysight / 21
2 Servicing the 1143A
Making Adjustments / 25
Disassembling The 1143A / 30
Troubleshooting The Power Supplies / 32
Troubleshooting The Offset Circuitry / 33
Replaceable Parts / 34
Theory of Operation / 48
Returning the Instrument For Service / 58

4 1143A Probe Offset Control and Power Module User’s Guide
Contents

5
Keysight 1143A Probe Offset Control and Power Module
User’s Guide
1 Using the 1143A
Safety Information 8
Using the 1143A 11
Remote Control 14
Characteristics 16
Testing Performance 19
Contacting Keysight 21
The 1143A Probe Offset Control and Power Module is an alternate control and
power source for active probes. When an active probe cannot be powered from a
connector at the front of the oscilloscope, the 1143A is used to provide power,
local offset control, and a remote offset interface.
Figure 1 1143A Front Panel
The 1143A provides:
• Power and control for two probes
• +17.3 Vdc and –17.3 Vdc at 300 mA each
• Offset current source of ±5 mA for each probe

6 1143A Probe Offset Control and Power Module User’s Guide
• Remote input for offset control
Accessories Supplied
The following accessories are supplied.
• Power cable
• User and Service Guide (this manual)
Accessories and Options
The 01143-61602, 1.5 meter (59-inch) probe power extension cable is available.
You can also order it with the 1143A as Option 001.
Initial Inspection
1Inspect the shipping container for damage.
Keep a damaged shipping container or cushioning material until the contents of
the shipment have been checked for completeness and the instrument has been
checked mechanically and electrically.
2Check the accessories. If the contents are incomplete or damaged notify your
Keysight Technologies sales office.
3Inspect the instrument.
• If there is mechanical damage or defect, or if the instrument does not operate
properly or pass performance tests, notify your Keysight Technologies sales
office.
• If the shipping container is damaged, or the cushioning materials show signs of
stress, notify the carrier as well as your Keysight Technologies sales office.
Keep the shipping materials for the carrier's inspection. The Keysight
Technologies office will arrange for repair or replacement at Keysight
Technologies' option without waiting for claim settlement.
Service Strategy
The service strategy for the 1143A Probe Offset Control and Power Module is for
field repair to the component level. Refer to Chapter 2, “Servicing the 1143A.

1143A Probe Offset Control and Power Module User’s Guide 7
To Clean The 1143A
Use a soft cloth dampened with mild soap and water to clean the instrument. Care
must be taken not to use a harsh soap which will damage the water-based paint
finish of the instrument.

8 1143A Probe Offset Control and Power Module User’s Guide
Safety Information
Safety Information
The following general safety precautions must be observed during all phases of
operation of this instrument. Failure to comply with these precautions or with
specific warnings or operating instructions in the product manuals violates safety
standards of design, manufacture, and intended use of the instrument. Keysight
Technologies assumes no liability for the customer's failure to comply with these
requirements.
Table 1 Instrument Markings
Marking Description
Instruction manual symbol: the product is marked with this symbol when it is necessary for you to refer
to the instruction manual in order to protect against damage to the product. "Caution" or "Warning"
risk of danger marked on product.
Hazardous voltage symbol.
Earth terminal symbol. Used to indicate a circuit common connected to grounded chassis.
Indicates AC (Alternating Current).
The CSA mark.
This symbol indicates the Environmental Protection Use Period (EPUP) for the product’s toxic
substances for the China RoHS requirements.
This product complies with the WEEE Directive marking requirements.

Safety Information
1143A Probe Offset Control and Power Module User’s Guide 9
General
Do not use this product in any manner not specified by the manufacturer. The
protective features of this product may be impaired if it is used in a manner not
specified in the operation instructions.
This apparatus has been designed and tested in accordance with IEC Publication
348, Safety Requirements for Measuring Apparatus, and has been supplied in a
safe condition. This is a Safety Class I instrument (provided with terminal for
protective earthing). Before applying power, verify that the correct safety
precautions are taken as described in the following warnings. In addition, note the
external markings on the instrument as described in Table 1 on page 8.
WARNING
If the instrument is damaged, or if it fails to operate according to the characteristics in
this manual, remove the power cord and contact Keysight Technologies.
WARNING
Only fuses with the required rated current, voltage, and specified type (normal blow,
time delay, etc.) should be used. Do not use repaired fuses or short-circuited fuse
holders. To do so could cause a shock or fire hazard.
WARNING
Before turning on the instrument, you must connect the protective earth terminal of the
instrument to the protective conductor of the (mains) power cord. The mains plug shall
only be inserted in a socket outlet provided with a protective earth contact. You must
not negate the protective action by using an extension cord (power cable) without a
protective conductor (grounding). Grounding one conductor of a two-conductor outlet
is not sufficient protection.
WARNING
If you energize this instrument by an auto transformer (for voltage reduction or mains
isolation), the common terminal must be connected to the earth terminal of the power
source.
WARNING
Whenever it is likely that the ground protection is impaired, you must make the
instrument inoperative and secure it against any unintended operation.

10 1143A Probe Offset Control and Power Module User’s Guide
Safety Information
WARNING
Service instructions are for trained service personnel. To avoid dangerous electric
shock, do not perform any service unless qualified to do so. Do not attempt internal
service or adjustment unless another person, capable of rendering first aid and
resuscitation, is present.
WARNING
Do not install substitute parts or perform any unauthorized modification to the
instrument.
WARNING
Capacitors inside the instrument may retain a charge even if the instrument is
disconnected from its source of supply.
WARNING
Do not operate the instrument in the presence of flammable gases or fumes. Operation
of any electrical instrument in such an environment constitutes a definite safety hazard.
WARNING
Do not subject the unit to vibration or shocks during transport or handling. Be
especially careful to avoid dropping the unit.
WARNING
When unplugging the power cord from the power receptacle or from the unit, grasp the
plug, not the cord, in order to avoid damaging the cable.
WARNING
This unit is not constructed to be waterproof or dust proof, so do not use it in a very
dusty environment or in one where it will get wet. For indoor use only.
WARNING
Do not use the instrument in a manner not specified by the manufacturer.

Using the 1143A
1143A Probe Offset Control and Power Module User’s Guide 11
Using the 1143A
This section of the manual contains information and instructions for installation
and use of the 1143A as an auxiliary power supply. Use of probe controls is
covered in the guide for the probe.
Checking the Power Requirements and Fuse
The power module requires a power source of either 115 Vac or 230 Vac, 47 to 440
Hz, 40VA maximum. The rear-panel fuse (F1) is a 0.25A, 250V time-delay fuse. The
fuse used is the same regardless of line voltage selection. To replace the fuse:
1Locate the fuse holder shown in Figure 2. Gently push the fuse holder in using
your finger or a flat-bladed screwdriver.
2While the fuse holder is pushed in, gently turn the fuse holder counterclockwise.
Figure 2 1143A Rear Panel
CAUTION
BEFORE CONNECTING POIWER TO THIS INSTRUMENT, be sure the line
voltage switch on the rear panel of the instrument is set properly. Applying a
voltage excessive to the setting may open the protective fuse.

12 1143A Probe Offset Control and Power Module User’s Guide
Using the 1143A
Setting Up the Line Voltage Selection
Before applying power, verify the setting of the LINE SELECT switch on the rear
panel. If the switch is set incorrectly, set it to either 115V or 230V, whichever is
appropriate for the voltage in your area. The fuse used is the same regardless of
input voltage selection.
Connecting The Probe
The following paragraphs cover system preparation using the 1143A. Refer also to
the probe’s user manual.
1Set the line voltage selection.
2Use the power cable to connect the power module to the ac mains.
3Connect the probe power cable 1143A’s front-panel Power connector. Red dots on
the cable connector housing and 1143A are aligned with the connector keys. Align
the dots when inserting the cable connector into the power connector.
4Connect the output of the probe to the input of the oscilloscope or other
instrument.
WARNING
SHOCK HAZARD! BEFORE YOU CONNECT THIS INSTRUMENT TO MAINS POWER OR LIVE
MEASURING CIRCUITS you must provide a protective earth ground. The Mains plug
must be inserted in a socket outlet provided with a protective earth contact.Do not use
an extension cord (power cable) without a protective conductor (grounding). Grounding
one conductor of a two-conductor outlet does not provide an instrument ground.
Failure to provide a protective earth ground could result in a shock hazard if there is a
failure in this instrument or equipment connected to it.
NOTE
This instrument is provided with a three-wire power cable. When connected to an appropriate
ac power outlet, this cable grounds the instrument cabinet. The type of power cable plug
shipped with the instrument depends on the country of destination.
CAUTION
The probe power cable connector automatically locks in the mating power connector. To
separate the connectors, you must pull on the knurled part of the cable connector
housing. This releases the lock. If you pull on the cable, the connectors won't release and
you may damage the connector or cable.

Using the 1143A
1143A Probe Offset Control and Power Module User’s Guide 13
To Use Local Offset
When setting the 1143A front-panel controls, be sure to use the controls that
correspond to the appropriate Power connector.
1Turn on the 1143A power.
2Set the appropriate Remote/Local switch.
• To control the probe offset voltage with the 1143A, set the switch to Local.
• To control the probe offset voltage remotely, set the switch to Remote and refer
to “Remote Control" on page 14.
3With Local control, set the appropriate Zero/Variable switch.
• To enable the local offset control, set the switch to Variable.
• To disable the local offset control, set the switch to Zero.
4Connect the probe to the signal to be measured.
5If you are using Variable offset, adjust the Coarse and Fine offset controls so the
desired part of the signal is displayed on the oscilloscope.
When the knobs are turned clockwise, the output of the probe goes positive. For
example, when using the probe with an oscilloscope, when the trace moves up,
the horizontal center line of the screen represents a more negative voltage. This
represents a negative offset.
NOTE
If you intend to use the probe with an instrument other than an oscilloscope, you may find it
easier to set up the probe with an oscilloscope first. This allows you to set the probe offset so
the output of the probe is compatible with the signal requirements of the other instrument.
After set-up, connect the output of the probe to the input of the other instrument.

14 1143A Probe Offset Control and Power Module User’s Guide
Remote Control
Remote Control
For automatic test applications, the offset provided by the 1143A can be remotely
controlled through the rear-panel a connector. This is a standard 9-pin, female,
D-sub-miniature connector shown in Table 2. This style is the same as that used
on some personal computer monitor cables, which provides an economical way to
connect the remote input to the controller interface on an automatic test system.
The following table gives the connections.
Operating Range
The remote variable offset can be used when the Local/Remote function is set to
Remote. The remote inputs for the two probe connectors are separate. The
following conditions apply:
• The remote offset input range is –10 to +10 Vdc. This provides a current of –5 to
+5 mA dc at the probe connector. With the 54701A Active Probe, this provides
an offset of –57.5 to +57.5 Vdc referenced to the probe tip.
• A positive, remote voltage input provides a negative offset in the probe. The
output of the probe goes positive. A negative, remote voltage input provides a
positive offset in the probe. The output of the probe goes negative.
• The offset voltage must be referenced to the appropriate (Probe 1 or Probe 2)
offset common of the remote input connector.
Table 2 Remote Input Connections
Pin Function Connector
1N.C.
2 Probe 1 offset common
3N.C.
4 Probe 2 offset common
5 Shield
6N.C.
7Probe1offset
8N.C.
9Probe2offset

Remote Control
1143A Probe Offset Control and Power Module User’s Guide 15
• To eliminate offset when using remote, the remote offset input must be set to
0.0V, disconnected, or grounded.
NOTE
To minimize dc offset errors and potential noise coupling caused by ground loops, electrically
isolate all connections between the remote input connector and the controlling system.

16 1143A Probe Offset Control and Power Module User’s Guide
Characteristics
Characteristics
Table 3 lists the performance characteristics for the 1143A. These characteristics
are nominal and non-warranted. Table 4 lists the operating characteristics. The
remainder of this section provides general characteristics.
Table 3 Performance Characteristics
Item Specification
Supply Output Voltage +17.3 Vdc ±500 mV
–17.3 Vdc ±500 mV
Supply Current 300 mA (for each supply)
Offset Voltage Variable from 0 to ±5 mA (for each probe)
Table 4 Operating Characteristics
Item Specification
Number of probes operated 2
Controls (for each probe) Remote/Local
Zero/Variable offset
Coarse and Fine offset
Remote Offset Input (for each probe) ±10 V for ±5 mA offset current

Characteristics
1143A Probe Offset Control and Power Module User’s Guide 17
Table 5 Environmental Conditions (General Characteristics)
Item Characteristic
Use Indoor
Temperature
Operating 0° C to +55° C (32° F to +131° F)
Non-operating –40° C to +70° C (–40° F to +158° F)
Humidity
Operating Up to 95% relative humidity (non-condensing) at +40° C (+104° F)
Non-operating Up to 90% relative humidity at +65° C (+149° F)
Altitude
Operating Up to 4,600 meters (15,000 ft)
Non-operating Up to 15,300 meters (50,000 ft)
Vibration
Operating Random vibration 5 to 500 Hz, 10 minutes per axis, 0.3, Grms.
Non-operating Random vibration 5 to 500 Hz, 10 minutes per axis, 2.41 Grms. Resonant search 5 to 500 Hz swept
sine, 1 octave/minute sweep rate, (0.75g), 5 minute resonant dwell at 4 resonances per axis.
Table 6 Power Requirements (General Characteristics)
Item Specification
Voltage 115/230 Vac, 47 to 440 Hz
Power 40 VA maximum
Table 7 Weight (General Characteristics)
Item Specification
Net approximately 1.5 kg (3.4 lb)
Shipping approximately 2.4 kg (5.4 lb)

18 1143A Probe Offset Control and Power Module User’s Guide
Characteristics
Figure 3 1143A Dimensions
Product Regulations
Safety
• CAN/CSA-C22.2 No. 61010-1-12
• ANSI/UL Standard 61010-1
• ANSI/ISA-61010-1 (82.02.01)

Testing Performance
1143A Probe Offset Control and Power Module User’s Guide 19
Testing Performance
The procedure in this section checks the probe power output voltage using the
value given in “Characteristics" on page 16 as a standard. This procedure may be
performed for incoming inspection of the 1143A and should be performed
periodically thereafter to ensure and maintain peak performance. The
recommended test interval is yearly or every 2,000 hours of operation. Amount of
use, environmental conditions, and the user's experience concerning need for
testing will contribute to verification requirements.
Equipment Required
The equipment required for this test is listed in the test. Any equipment satisfying
the critical specifications listed may be substituted for the recommended model.
To Test Output Voltages
This test checks the output voltages of the supply. The voltage requirement is not
a specification, but is checked to assure proper operation of the probes.
Requirement: +17.3 Vdc ±500 mV and –17.3 Vdc ±500 mV
Use Figure 4 on page 20 to locate the correct pins of the probe power connectors.
Either connector can be measured to check the voltage accuracy. Both can be
measured to assure both connectors have power.
Table 8 Equipment Required
Equipment Critical Specification Recommended
Model/Part
Digital Multimeter Better than 0.1% accuracy 3458A