Pickering 40-252 User manual

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Issue 1.4 January 2020
40-252 User Manual
PXI 5W Programmable Resistor Module

Page (II) 5W PROGRAMMABLE RESISTOR MODULE 40-252
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Page (II) REED RELAY MODULE 40-110/115/120/125
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© COPYRIGHT (2020) PICKERING INTERFACES. ALL RIGHTS RESERVED.
No part of this publication may be reproduced, transmitted, transcribed, translated or stored in any form, or by
any means without the written permission of Pickering Interfaces.
Technical details contained within this publication are subject to change without notice.
ISO 9001
Reg No. FM38792

Page (III)
5W PROGRAMMABLE RESISTOR MODULE 40-252
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Page (III)
REED RELAY MODULE 40-110/115/120/125
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TECHNICAL SUPPORT
For Technical Support please contact Pickering Interfaces either by phone, the website or via e-mail.
WARRANTY
All products manufactured by Pickering Interfaces are warranted against defective materials and workmanship for a period of
three years, excluding programmable power supplies, from the date of delivery to the original purchaser. Any product found to be
defective within this period will, at the discretion of Pickering Interfaces be repaired or replaced.
Products serviced and repaired outside of the warranty period are warranted for ninety days.
Extended warranty and service are available. Please contact Pickering Interfaces by phone, the website or via e-mail.
ENVIRONMENTAL POLICY
Pickering Interfaces operates under an environmental management system similar to ISO 14001.
Pickering Interfaces strives to full all relevant environmental laws and regulations and reduce wastes and releases to the
environment. Pickering Interfaces aims to design and operate products in a way that protects the environment and the health and
safety of its employees, customers and the public. Pickering Interfaces endeavours to develop and manufacture products that can
be produced, distributed, used and recycled, or disposed of, in a safe and environmentally friendly manner.
Worldwide Technical Support and Product Information
pickeringtest.com
Germany
Tel: [phone]
E-mail: [email protected]
Sweden
Tel: [phone]
E-mail: [email protected]
USA
Tel: (West) [phone]
Tel: (East) [phone]
E-mail: [email protected]
Czech Republic
Tel: [phone]
E-mail: [email protected]
France
Tel [phone]
E-mail [email protected]
Pickering Interfaces Headquarters
Stephenson Road Clacton-on-Sea CO15 4NL United Kingdom
Tel: [phone]
E-Mail: [email protected]
China
Tel: [phone]
E-mail: [email protected]

Page (IV) 5W PROGRAMMABLE RESISTOR MODULE 40-252
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Page (IV) REED RELAY MODULE 40-110/115/120/125
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MEANING / DESCRIPTION SYMBOL
PROTECTIVE EARTH (GROUND)
To identify any terminal which is intended for connection to an external conductor for
protection against electric shock in case of a fault, or the terminal of a protective earth
(ground) electrode.
DANGEROUS VOLTAGE
To indicate hazards arising from dangerous voltages.
WARNING / CAUTION
An appropriate safety instruction should be followed or caution to a potential hazard
exists.
Refer to the relevant instructions detailed within the product manual.
HEAVY
If this product is heavy reference should be made to the safety instructions for
provisions of lifting and moving.
STATIC SENSITIVE
To indicate that static sensitive devices are present and handling precautions should
be followed.
!
kg
SAFETY SYMBOLS
PRODUCT SAFETY
The following safety symbols may be used on the product and throughout the product documentation.

Page (V)
5W PROGRAMMABLE RESISTOR MODULE 40-252
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Copyright Statement ...................................................................II
Technical Support and Warranty................................................III
Product Safety .............................................................................IV
Contents (this page)....................................................................V
Warnings and Cautions ..............................................................VII
Section 1
Technical Specication...............................................................1.1
Section 2
Technical Description .................................................................2.1
Functional Description..........................................................2.1
Guidance on Using the Module............................................2.2
Section 3
Installation....................................................................................3.1
Pre Operation Checks...........................................................3.1
Hardware Installation ............................................................3.2
Software Installation .............................................................3.2
Testing Operation ..................................................................3.3
Section 4
Programming Guide....................................................................4.1
Programming Options For Pickering PXI Modules ............4.1
Module Architecture..............................................................4.2
Programming Module............................................................4.2
Using The Soft Front Panel ..................................................4.4
Section 5
Connector Information................................................................5.1
Section 6
Trouble Shooting .........................................................................6.1
Section 7
Maintenance Information............................................................7.1
Verication & Adjustment Procedure ..................................7.2
Verication Test Results .......................................................7.9
CONTENTS

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THIS PAGE INTENTIONALLY BLANK

Page (VII)
5W PROGRAMMABLE RESISTOR MODULE 40-252
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Page (VII)
2 AMP 1-POLE UHD MATRIX MODULES 40-575 / 576 / 577 / 578 / 579
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WARNINGS AND CAUTIONS
WARNING - HAZARDOUS ENVIRONMENTS SYMBOL
This product is not specically designed for use in hazardous environments, for example in explosive
atmospheres. If the product is to be used in hazardous environments we recommend that the user
ensures suitable protective measures are taken.
!
WARNING - DANGER OF ELECTRIC SHOCK SYMBOL
This module may contain hazardous voltages. Before removing the module from the rack remove all
supplies and disconnect user I/O signals.
Unused slots in the host chassis are populated with blanking plates to prevent access to user I/O
signals that may be present. Blanking panels are available to order from Pickering in a variety of
slot widths. If the product is not used in this manner for example by using an extender card then
additional care must be taken to avoid contact with exposed signals.
Not to be used in safety critical circuits, refer to the Pickering Interfaces’ terms & conditions of sale.
This module must not be used for the switching of Mains Circuits. For the switching of voltages up
to the module’s full specication, Secondary Circuit power supplies and the Device Under Test must
be fully isolated from the Mains Circuit and the safety earth.
The host chassis must be correctly installed and be connected to mains or factory safety ground,
please refer to your chassis installation manual.
Diagram Showing Separation Between The Mains Circuit and Secondary Circuit / DUT
For the purposes of this document, a Mains Circuit is an installation classied as Overvoltage
Category II up to 300V. Separation between the Secondary Circuit and Mains Circuit is achieved
by a transformer in which the primary windings are separated from the secondary windings by
reinforced insulation, double insulation, or a screen connected to the protective conductor terminal.
CAUTION - HANDLING OF ELECTROSTATIC-SENSITIVE DEVICES SYMBOL
Certain semiconductor devices used in this equipment are liable to damage due to static voltage.
Observe the following precautions when handling these devices in their unterminated state, or
sub-assemblies containing these devices:
1. Persons removing sub-assemblies from equipment using these devices must be earthed by a
wrist strap and a resistor at the point provided on the equipment.
2. Soldering irons used during the repair operations must be low voltage types with earthed tips and
isolated from the mains voltage by a double insulated transformer.
3. Outer clothing worn must be unable to generate static charges.
4. Printed Circuit Boards (PCBs) tted with these devices must be stored and transported in
anti-static bags.
PXI Switching
Module
Device
Under Test
Power
Supply
Power
Supply
Host Chassis
Secondary Circuit
Mains
Circuit
Mains
Circuit
Mains/Factory
Safety Ground

Page (VIII) 5W PROGRAMMABLE RESISTOR MODULE 40-252
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Page (VIII) 2 AMP 1-POLE UHD MATRIX MODULES 40-575 / 576 / 577 / 578 / 579
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CAUTION - PRODUCT DOCUMENTATION SYMBOL
Suitably qualied & trained users should ensure that the accompanying documentation is fully read
and understood before attempting to install or operate the product.
!
SAFETY INSTRUCTIONS
SAFETY INSTRUCTIONS
All cleaning and servicing requires the equipment to be isolated and disconnected from the power source and user I/O
signals (refer to the Maintenance Section).
• Appropriate manual handling procedures should be followed as dictated by the weight of the individual module or
the combined weight of the modules & chassis.
• Should a fault occur with the module or chassis, immediately isolate and disconnect the incoming power to the
chassis and the user I/O signals.
• Ensure the equipment is installed, operated and maintained by trained and authorised personnel.
• For suitably equipped products in the event of an emergency press the red “emergency stop” button situated on
the front of the unit.

Page 1.1
5W PROGRAMMABLE RESISTOR MODULE 40-252
pickering SECTION 1 - TECHNICAL SPECIFICATION
SECTION 1 - TECHNICAL SPECIFICATION
pickeringtest.com
PXI 5W Programmable Resistor Module 40-252
ISSUE F NOV 2019
Up to 4
Up to 4
37-pin
D-type
Plug
Resistor
Channel
Switched
Resistor
Functional Diagram for the 40-252 5W
Programmable Resistor Module
• Up To 5W Per Channel
• Up To 4 Channels in a One Slot Module
• Resistance Resolution to 0.125Ω
• Values From 1Ω to 22MΩ
• Short and Open Simulation
• Simple Software Control Through
Resistance Calls
• VISA & Kernel Drivers Supplied for
Windows
• Supported by PXI or LXI Chassis
• 3 Year Warranty
Part of a growing range of medium to high power
resistor modules, the 40-252 provides a simple
solution for applications requiring up to 5W of power
handling capability. The 40-252 is available in a
variety of resistance ranges and resolutions that
meet the needs of most functional test systems.
Each channel of the 40-252 is able to simulate
short circuit and open circuit conditions that can be
experienced in a system caused by faulty wiring or
sensors.
Software control is simplied by the use of resistor
value calls. The module works out the resistance
setting closest to the requested value and sets that
value. The user can interrogate the module to nd
the actual setting used.
A calibration cable assembly can be attached to
the module in place of the UUT to enable a DMM
to be used for verifying the resistor channels. This
considerably simplies the checking of the module’s
calibration.
The 40-252 is available in 40 standard builds that suit the most common
congurations:
• Narrow resistance range version, available in 2 or 4 channel variants.
• Medium resistance range version, available in 1 or 2 channel variants.
• Wide resistance range version, available in 1 channel variants.
For applications requiring greater density with lower power, users should
consider the 40-297 High Density Precision Resistor Modules.
Pickering’s Range of PXI Resistor Modules
Model No. Description Channels Range
40-251 2.5W Programmable Resistor 1, 2, 4 or 8 Up to 22MΩ
40-252 5W Programmable Resistor 1, 2, or 4 Up to 22MΩ
40-253 10W Programmable Resistor 1 or 2 Up to 102kΩ
40-280/1/2 Selectable 12 to 48 User Specied
40-290 Programmable Resistor 20.5Ω to 32kΩ
40-291 4 0.5Ω to 128Ω
40-292 Programmable Load 1 40Ω to 295Ω or
10Ω to 2.56kΩ
40-293 Programmable Resistor + SPDT 2 or 4 Up to 131kΩ
40-294 Programmable Resistor + SPST 2 or 4 Up to 131kΩ
40-295 Programmable Resistor 3, 6, 5,
10 or 18 Up to 16MΩ
40-296 Programmable Potentiometer 1, 2, 3, 4,
5 or 9 Up to 16MΩ
40-297 High Density Precision Resistor 3, 4, 6,
9 or 18 Up to 22.3MΩ
40-298
Precision Resistor Modules
For applications requiring a Resistor Module with greater resolution (to <2mΩ) or better
accuracy (to <0.03%), look to our Precision Resistor range which includes models
40-260, 40-261, 40-262, 40-265, and 40-297
Custom Resistor Modules
If our range of Resistor Modules does not meet your specic requirements, please
contact you local sales ofce to discuss your application. Customizations include:
different start and stop values, current, power, voltage, precision, accuracy, number of
channels, connector etc.

Page 1.2 5W PROGRAMMABLE RESISTOR MODULE 40-252
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SECTION 1 - TECHNICAL SPECIFICATION
5W Programmable Resistor – 40-252
pickeringtest.com
Overview
Soft Front Panel for the Programmable Resistor Module
Graphical Representation of the 40-252 Programmable Resistor Module Range
PXI Part Number
(Number of Channels)
Resistance Range
Resolution
1Ω 10Ω 100Ω 1kΩ 10kΩ 100kΩ 1MΩ 10MΩ 100MΩ
40-252-010 (4) 40-252-110 (2) 0.125Ω
40-252-011 (4) 40-252-111 (2) 0.25Ω
40-252-012 (4) 40-252-112 (2) 0.5Ω
40-252-013 (4) 40-252-113 (2) 1Ω
40-252-014 (4) 40-252-114 (2) 2Ω
40-252-020 (2) 40-252-120 (1) 0.125Ω
40-252-021 (2) 40-252-121 (1) 0.25Ω
40-252-022 (2) 40-252-122 (1) 0.5Ω
40-252-023 (2) 40-252-123 (1) 1Ω
40-252-024 (2) 40-252-124 (1) 2Ω
40-252-030 (2) 40-252-130 (1) 0.125Ω
40-252-031 (2) 40-252-131 (1) 0.25Ω
40-252-032 (2) 40-252-132 (1) 0.5Ω
40-252-033 (2) 40-252-133 (1) 1Ω
40-252-034 (2) 40-252-134 (1) 2Ω
40-252-040 (1) 0.125Ω
40-252-041 (1) 0.25Ω
40-252-042 (1) 0.5Ω
40-252-043 (1) 1Ω
40-252-044 (1) 2Ω
40-252-050 (1) 0.125Ω
40-252-051 (1) 0.25Ω
40-252-052 (1) 0.5Ω
40-252-053 (1) 1Ω
40-252-054 (1) 2Ω

Page 1.3
5W PROGRAMMABLE RESISTOR MODULE 40-252
pickering SECTION 1 - TECHNICAL SPECIFICATION
5W Programmable Resistor – 40-252
pickeringtest.com
Specifications
Specifications
Accuracy (low power): ±0.3% ±Resolution @ ±10°C
from calibration temperature
(factory calibration @ 21°C)
Fault Simulation: Open and short circuit (typically <0.3Ω)
Power: 5W maximum per channel†
Maximum Current: 1A or as limited by power
Maximum Voltage: 100V* or as limited by power
Settling time: <3ms‡
Number of Operations: 1x108 (low power), 1x106 (high power)
Software Control: By resistance calls to module for
selected channel.
Calibration: 4-wire resistance measurement of
selected channel for verication
purposes with UUT removed and a
special cable assembly attached.
Factory calibration data is stored in the
module.
* For full voltage rating, signal sources must be fully isolated from
mains supply and safety earth.
† Or as limited by voltage/current, refer to power plot for
guidance.
‡ The total operate time when setting a resistance may be longer
depending upon the change requested due to relay sequencing.
10 1001 1000 10000 100000 1000000 10000000
0
1
2
3
4
5
6
Current
Limited
Voltage
Limited
Set Resistance (Ω)
Power (W)
40-252 Maximum Power for a
Given Resistance Setting
Power Requirements
+3.3V +5V +12V -12V
0.3A 0.5A 0 0
Mechanical Characteristics
1 slot 3U PXI (CompactPCI card).
3D models for all versions in a variety of popular le formats are
available on request.
Connectors
PXI bus via 32-bit P1/J1 backplane connector.
Resistor channels via front panel 37-pin male D-Type connector.
For pin outs please refer to the operating manual.
Operating/Storage Conditions
Operating Conditions
Operating Temperature:
Humidity:
Altitude:
0°C to +55°C
Up to 90% non-condensing
5000m
Storage and Transport Conditions
Storage Temperature:
Humidity:
Altitude:
-20°C to +75°C
Up to 90% non-condensing
15000m
PXI & CompactPCI Compliance
The module is compliant with the PXI Specication 2.2. Local Bus,
Trigger Bus and Star Trigger are not implemented.
Uses a 33MHz 32-bit backplane interface.
Safety & CE Compliance
All modules are fully CE compliant and meet applicable EU
directives: Low-voltage safety EN61010-1:2010, EMC Immunity
EN61326-1:2013, Emissions EN55011:2009+A1:2010.

Page 1.4 5W PROGRAMMABLE RESISTOR MODULE 40-252
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SECTION 1 - TECHNICAL SPECIFICATION
5W Programmable Resistor – 40-252
pickeringtest.com
Ordering Information
Resistor Module Order Codes
0.125Ω Resolution
Range No. of
Channels
Order
Code
No. of
Channels
Order
Code
1Ω to 31.5Ω 240-252-110 440-252-010
1.5Ω to 472Ω 140-252-120 240-252-020
2Ω to 6.97kΩ 140-252-130 240-252-030
2.5Ω to 102kΩ 140-252-040
3Ω to 1.51MΩ 140-252-050
0.25Ω Resolution
Range No. of
Channels
Order
Code
No. of
Channels
Order
Code
1Ω to 62.1Ω 240-252-111 440-252-011
1.5Ω to 925Ω 140-252-121 240-252-021
2Ω to 13.6kΩ 140-252-131 240-252-031
2.5Ω to 201kΩ 140-252-041
3Ω to 2.97MΩ 140-252-051
0.5Ω Resolution
Range No. of
Channels
Order
Code
No. of
Channels
Order
Code
1Ω to 122Ω 240-252-112 440-252-012
1.5Ω to 1.81kΩ 140-252-122 240-252-022
2Ω to 26.7kΩ 140-252-132 240-252-032
2.5Ω to 395kΩ 140-252-042
3Ω to 5.82MΩ 140-252-052
1Ω Resolution
Range No. of
Channels
Order
Code
No. of
Channels
Order
Code
1Ω to 239Ω 240-252-113 440-252-013
1.5Ω to 3.55kΩ 140-252-123 240-252-023
2Ω to 52.4kΩ 140-252-133 240-252-033
2.5Ω to 773kΩ 140-252-043
3Ω to 11.4MΩ 140-252-053
2Ω Resolution
Range No. of
Channels
Order
Code
No. of
Channels
Order
Code
1Ω to 470Ω 240-252-114 440-252-014
1.5Ω to 6.97kΩ 140-252-124 240-252-024
2Ω to 102kΩ 140-252-134 240-252-034
2.5Ω to 1.51MΩ 140-252-044
3Ω to 22.3MΩ 140-252-054
Product Customization
Pickering PXI modules are designed and manufactured on our own
exible manufacturing lines, giving complete product control and
enabling simple customization to meet very specic requirements.
Customization can include:
• Alternative resistance range
• Alternative resolution
• Different number of channels
• Different performance specications
All customized products are given a unique part number, fully
documented and may be ordered at any time in the future. Please
contact your local sales ofce to discuss.
Other Resistor Modules
Pickering Interfaces manufacture a range of variable resistor
modules in the PXI format. If you have a requirement for a variable
resistor module please contact your local sales ofce with the
information below and we will advise you on the best solution for
your application.
Lowest Resistance †
Highest Resistance
Resistance Resolution
Overall Accuracy
Maximum Power/Current
Number of Channels (variable resistors)
†Resistance is as measured across the user connector terminals,
minimum resistance must have a non-zero value.
Mating Connectors & Cabling
For connection accessories for the 40-252 please refer to the
90-007D 37-pin D-Type Connector Accessories data sheet where
a complete list and documentation can be found for accessories,
or refer to the Connection Solutions catalog.
Accessories
Calibration lead for 4-wire DMM resistance
measurement - 37-pin D-type socket to
shrouded 4mm bayonet plugs, 1m length 40-975-037-1m

Page 1.5
5W PROGRAMMABLE RESISTOR MODULE 40-252
pickering SECTION 1 - TECHNICAL SPECIFICATION
5W Programmable Resistor – 40-252
pickeringtest.com
Supporting Products & Software
We also offer customized cabling and have a free online Cable Design Tool that can be
used to create custom cable solutions for many applications.
Visit: pickeringtest.com/cdt to start your design.
Mass Interconnect
We recommend the use of a mass interconnect solution when an Interchangeable Test
Adapter (ITA) is required for a PXI or LXI based test system. Our modules are fully
supported by both Virginia Panel and MacPanel.
Pickering Reed Relays
We are the only switch provider with in-house reed relay manufacturing capability via
our sister company, Pickering Electronics. These instrument grade reed relays feature
SoftCenter® technology, ensuring long service life and repeatable contact performance.
To learn more, please go to: pickeringrelay.com
Chassis Compatibility
This PXI module must be used in a suitable chassis. It is compatible with the following chassis types:
• All chassis conforming to the 3U PXI and 3U Compact PCI (cPCI) specication
• Legacy and Hybrid Peripheral slots in a 3U PXI Express (PXIe) chassis
• Pickering Interfaces LXI or LXI/USB Modular Chassis
Chassis Selection Guide
Standard PXI or hybrid PXIe Chassis from any Vendor:
• Mix our 1000+ PXI switching & simulation modules with any
vendor’s PXI instrumentation
• Embedded or remote Windows PC control
• Real-time Operating System Support
• High data bandwidths, especially with PXI Express
• Integrated module timing and synchronization
Pickering LXI or LXI/USB Modular Chassis—only accept
our 1000+ PXI Switching & Simulation Modules:
• Ethernet or USB control enables remote operation
• Low-cost control from practically any controller
• LXI provides manual control via Web browsers
• Driverless software support
• Power sequencing immunity
• Ethernet provides chassis/controller voltage isolation
• Independence from Windows operating system
Connectivity Solutions
We provide a full range of supporting cable and connector solutions for all our switching products—20 connector families with 1200+
products. We offer everything from simple mating connectors to complex cables assemblies and terminal blocks. All assemblies are
manufactured by Pickering and are guaranteed to mechanically and electrically mate to our modules.
Connectors & Backshells Multiway Cable Assemblies RF Cable Assemblies Connector Blocks

Page 1.6 5W PROGRAMMABLE RESISTOR MODULE 40-252
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SECTION 1 - TECHNICAL SPECIFICATION
5W Programmable Resistor – 40-252
pickeringtest.com
Supporting Products & Software
© Copyright (2020) Pickering Interfaces. All Rights Reserved Pickering Interfaces maintains a commitment to continuous product development, consequently we reserve the right to vary from the description given in this data sheet.
Programming
Pickering provide kernel, IVI and VISA (NI & Keysight) drivers which are compatible with all Microsoft supported versions of Windows and
popular older versions. For a list of all supporting operating systems, please see: pickeringtest.com/os
The VISA driver is also compatible with Real-Time Operating Systems such as LabVIEW RT. For other RTOS support contact Pickering.
These drivers may be used with a variety of programming environments and applications including:
• Pickering Interfaces Switch Path Manager
• National Instruments products (LabVIEW, LabWindows/CVI, Switch Executive, MAX, TestStand, VeriStand, etc.)
• Microsoft Visual Studio products (Visual Basic, Visual C+)
• Keysight VEE and OpenTAP
• Mathworks Matlab
• Marvin ATEasy
• MTQ Testsolutions Tecap Test & Measurement Suite
Drivers for popular Linux distributions are available, other environments are also supported, please contact Pickering with specic enquiries.
We provide Soft Front Panels (SFPs) for our products for familiarity and manual control, as well as comprehensive documentation and
example programs to help you develop test routines with ease.
To learn more about software drivers and development environments, please go to:
pickeringtest.com/software
Signal Routing Software
Our signal routing software, Switch Path Manager, automatically selects and energizes switch
paths through Pickering switching systems. Signal routing is performed by simply dening test
system endpoints to be connected together, greatly accelerating Test System software
development. To learn more, please go to: pickeringtest.com/spm
Diagnostic Relay Test Tools
eBIRST Switching System Test Tools are designed specically for our PXI, PCI or LXI
products, these tools simplify switching system fault-nding by quickly testing the system
and graphically identifying the faulty relay.
To learn more, please go to: pickeringtest.com/ebirst
Three Year Warranty & Guaranteed Long-Term Support
All standard products manufactured by Pickering Interfaces are warranted against defective materials and workmanship for a period of three
years from the date of delivery to the original purchaser. Extended warranty and service agreements are available for all our modules and
systems with various levels to suit your requirements. Although we offer a 3-year warranty as standard, we also include guaranteed long-
term support—with a history of supporting our products for typically 15-20 years. To learn more, please go to: pickeringtest.com/support
Available Product Resources
We have a large library of product resources including success stories, product and support videos, articles, as well as complete product
catalogs and product reference maps to assist when looking for the switching, simulation and cable and connector solutions you need.
We have also published handy reference books on Switching Technology and for the PXI and LXI standards.
To view, download or request any of our product resources, please visit: pickeringtest.com/resources

Page 2.1
5W PROGRAMMABLE RESISTOR MODULE 40-252
pickering SECTION 2 - TECHNICAL DESCRIPTION
SECTION 2 - TECHNICAL DESCRIPTION
FUNCTIONAL DESCRIPTION
A functional block diagram is provided in Figure 2.1. The Programmable Resistor Module is powered by +3.3V and
+5V inputs via Compact PCI connector J1. The interface to the user test equipment is via the front panel mounted
37-pin D-type connector, J2. The module comprises two PCBs populated with resistor chains which are switched
via two pole electro-mechanical relays. The two PCBs are connected via a plug and socket connector arrangement.
The relays are energised via control signals from relay drivers which are addressed by PCI bridge via control logic
to output the required signal.
The module is factory congured to have different channel counts and different bits per channel as dened by the
specic part number. Each resistor channel includes relay contacts to hold the channel open circuit or short circuit.
Figure 2.1 - 5W Programmable Resistor Module 40-252: Functional Block Diagram
1 or 2 Resistor Channels
1 or 2 Resistor Channels
Daughter Board
(40-252-0xx only)
Relay
Drivers
U10-12
Relay
Drivers
U6-8
PCI Bridge
Configuration
U5
Bus
Switches
U1-2
PCI Bridge U3
Mother Board
(40-252-1xx
& 40-252-0xx)
+3.3V
GND
Control Logic
& Module
Configuration
Memory
Compact PCI Bus Connector J1
Front Panel Connector J2
37-pin Male D-type
Interconnection
PXI 5W PROGRAMMABLE
RESISTOR MODULE 40-252
+5V

Page 2.2 5W PROGRAMMABLE RESISTOR MODULE 40-252
pickering
SECTION 2 - TECHNICAL DESCRIPTION
GUIDANCE ON USING THE MODULE
The 40-252 behaves as a precise but adjustable in value resistor. The circuit elements in the design use switch
resistors with electro-mechanical relays. It can be used to simulate the type of variable resistor found in many control
systems that indicate the value of a parameter, such as temperature, strain or pressure.
The 40-252 responds directly to a request for a particular value of resistance and is therefore very easy to use in
a system. Applications programs are easily generated to convert, for example, temperature requests to resistance
values for different types of RTD that are to be emulated.
Each resistor channel has an “input” connection and an “output” connection. There is no signicance in the label
“input” and “output” other than to identify them. The resistor channel schematic is shown in Figure 2.2.
The module uses xed resistor values switched by relays. There are no user adjustable parts
A table containing calibration data is used to convert requests for specic resistance values to a setting which most
closely corresponds to the value requested. The module contains two versions of the calibration table, one created
by Pickering Interfaces at the point of manufacture and an alternate table which can be created by the user. The
Pickering Interfaces table cannot be overwritten by the user. The user can select which table is being is used, in
the majority of applications we recommend the Pickering Interfaces table is used, creation of a user table requires
accurate measurements of many points within the module and requires a program to create with condence. A
program is available for this purpose from Pickering Interfaces but requires the use of a specic DMM range.
For applications requiring the greatest accuracy Pickering Interfaces does offer a range of other resistor modules
with better accuracy.
Potentiometer Operation
The 40-252 can be used to simulate a potentiometer by using the two channels connected in series. The user
should decide on the value of the potentiometer to be simulated and program two channels so that the sum of their
resistances is always the same. For example, if a 5kΩ potentiometer is needed with a wiper position at 1kΩ, set one
channel to 1kΩ and the other to 4kΩ.
Figure 2.2 - Resistor Channels for 40-252 4-Channel 5W Programmable Resistor
CHANNEL 1
RESISTOR CHANNEL CONNECTOR
IN OUT
CHANNEL 2
IN OUT
CHANNEL 4
IN OUT
CHANNEL 3
IN OUT

Page 3.1
5W PROGRAMMABLE RESISTOR MODULE 40-252
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Page 3.1
REED RELAY MODULE 40-110/115/120/125
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kg
PREOPERATION CHECKS (UNPACKING)
1. Check the module for transport damage and report any damage immediately to Pickering Interfaces.
Do not attempt to install the product if any damage is evident.
2. Position the chassis relative to any other equipment the module(s) will connect with. Ensure the chassis is not
connected to the electrical supply.
3. Ensure that the designated area for the chassis containing the module is of at and solid construction to
withstand and support the combined weight of the module(s) and chassis.
SECTION 3 - INSTALLATION
!
Refer to the Warnings and Cautions at the front of this manual
Modular products require installation in a suitable PXI/LXI chassis. The module is designed for indoor use only.
Figure 3.1 - Installing the Module into a PXI/cPCI/LXI Chassis
PXI / LXI Chassis

Page 3.2 5W PROGRAMMABLE RESISTOR MODULE 40-252
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SECTION 3 - INSTALLATION
Page 3.2 REED RELAY MODULE 40-110/115/120/125
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SECTION 3 - INSTALLATION
SOFTWARE INSTALLATION
First install the appropriate Pickering PXI switch card drivers by running the installer program Setup.exe (provided
in a compressed zip le), either from the CD-ROM supplied, or by downloading the latest version from our website
pickeringtest.com - the recommended method. Setup is accompanied by a ReadMe le containing
additional installation information. A single installation covers all cards in the System 40, System 45 and System
50 ranges.
When installation completes, the installed drivers’ ReadMe le is offered for display. It can also be displayed
later using a shortcut on the Programs>>Pickering menu.
If you are not a LabVIEW user you should choose the “full” version, and once that has been installed run
the LabVIEW Runtime Engine installer via the shortcut on the Programs>>Pickering menu. In the absence of
LabVIEW the Runtime Engine is required to support the Pickering Test Panels application.
!
HARDWARE INSTALLATION
ELECTRICAL CONNECTION (CHASSIS)
1. The chassis must be electrically installed in accordance with local regional electrical codes by a qualied
engineer.
2. The chassis must be grounded.
Electrostatic discharge can damage the components on the module. To avoid such damage in handling the
board refer to page VII.
Ensure that there is adequate ventilation.
The module should be installed in accordance with the following procedure:
1. Ensure that the system is turned OFF but still connected to mains so that it remains grounded.
2. Choose an appropriate slot in the rack.
3. Remove the blanking plate for the chosen slot.
4. Ensure that the injector/ejector handle is in its downward position. Align the module with the card guides on
the top and bottom of the slot.
Do not raise the injector/ejector handle whilst inserting the module as the module will not insert properly.
5. Hold the handle whilst slowly sliding the module into the card guides until the handle catches on the injector/
ejector rail (refer to Figure 3.1).
6. Raise the injector/ejector handle until the module rmly seats into the backplane. The front panel of the
module should be ush with the front panel of the chassis.
7. Secure the front panel of the module using both screws to the chassis front panel mounting rails.
8. In a system employing a remote control interface to connect an external controller to a PXI chassis or to link
multiple chassis, power-up the system as follows:
a. For a system comprising an external controller and one chassis, power up the chassis before powering up
the external controller.
b. For a system comprising more than one chassis, turn ON the last chassis in the system followed by the
penultimate, etc, and nally turn ON the external controller or chassis containing the system controller.
9. For Pickering Interfaces modular LXI installation there is no requirement to use any particular power up
sequence.

Page 3.3
5W PROGRAMMABLE RESISTOR MODULE 40-252
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Page 3.3
REED RELAY MODULE 40-110/115/120/125
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Figure 3.3 - General Soft Front Panel Selector
TESTING OPERATION
After installation of the hardware and Pickering PXI Driver software package start the General Soft Front
Panel (GSFP) using the desktop icon or via the Start menu (Start Menu-> Pickering Interfaces Ltd ->
General Soft Front Panel).
A selector panel will appear, listing all installed Pickering PCI, PXI or LXI switch cards and resistor cards. Click
on the card you wish to control, and a graphical control panel is presented allowing operation of the card.
Panels can be opened simultaneously for all the installed cards.
More details how to use the GSFP can be found in the manual, via menu Help\Manual
Figure 3.2 - General Soft Front Panel Icon

Page 3.4 5W PROGRAMMABLE RESISTOR MODULE 40-252
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