Save Time and Maximize Reuse in HIL Testing with the SLSC Extension for PXI and CompactRIO

Panoramica

NI SLSC (Switch, Load and Signal Conditioning) is an add-on for NI data acquisition products like PXI and CompactRIO. SLSC standardizes connectivity and provides a modular approach to signal conditioning, fault insertion and other test needs. This white paper discusses the details of SLSC and showcases the growing ecosystem of SLSC modules and accessories created by NI and NI partners.

Contents

What is SLSC?

As technology advances, embedded software is becoming increasingly prevalent in complex, safety critical systems such as automobiles and aircraft. Hardware-in-the-loop (HIL) testing is a methodology adopted by many industries to test embedded software while simulating the real-world inputs to that system. This approach allows testers to test early and often without risking damage to costly hardware and without incurring safety risks associated with unvetted product.

Because successful HIL testing hinges on accurately simulating real-world signals, custom signal conditioning and in-house development of simulated loads to guarantee signal integrity has been the norm. While it’s true that no one is as knowledgeable about specific test requirements as the test engineer working on the system, NI has observed that much of this custom engineering is common across companies and industries. This observation lead to the development of SLSC, an add-on to NI’s powerful measurement and control platform that streamlines signal conditioning and test stimulus needs.

SLSC Extends the Functionality of Measurement and Control Hardware Such as PXI

SLSC extends PXI and CompactRIO and consists of a chassis with modules. Each module has a Rear Transition Interface (RTI) which provides flexible standardized connectivity from SLSC to PXI or CompactRIO. Additionally, an SLSC system has a standard pinout that allows for the use of standard cables and eliminates point to point wiring.


SLSC plug-in modules can operate in the chassis in three different modes: stand alone, pass through, or cascaded. Cascaded mode can be used to cascade the signal path through multiple SLSC modules and implement functionality like signal fault insertion. You can choose from a variety of third-party modules or create your own modules based on a detailed hardware and software module development kit (MDK) from NI.

SLSC hardware is designed to simplify overall system integration by reducing system point-to-point wiring through signal accumulation and standard cable use. Each SLSC chassis consists of an SLSC digital bus, which you can use to discover, configure, and set parameters on the individual modules. Signals pass through SLSC modules either from the front connector or the rear transition interface (RTI) connector. You have the flexibility to design your own secondary backplane RTIs to reduce system wiring.

HIL System Diagram with SLSC

SLSC sits between the DUT/UUT and the data acquisition device you’re using

An SLSC system is comprised of four different component types: chassis, modules, rear transition interfaces (RTIs), and cables.  The chassis and architecture have been designed and are produced by National Instruments with both NI and partners producing components that complete the ecosystem.

  • SLSC Chassis – The SLSC chassis in conjunction with PXI is designed to handle more power and provide more board footprint than PXI alone, which makes it ideal for high power loads, switching, and signal conditioning.  The chassis handles communication to the modules as well as mechanical fixturing and cooling.
  • SLSC Modules – SLSC modules provide the switching, load simulation, or signal conditioning for the signal paths.  Modules can communicate and be powered through the SLSC chassis or through auxiliary lines on the modules themselves.
  • Rear Transition Interface (RTI) – The RTIs provide standard connectivity from SLSC modules to commercial off the shelf (COTS) cable options and back to DAQ modules.  RTIs are generally SLSC module agnostic and are chosen based on the connectivity and cabling desired to bring signals back to the PXI or cRIO system.
  • Cabling – One of SLSC’s greatest strengths is reducing time consuming and expensive point to point wiring by allowing signals to be passed around through banks within standard available cables.  A variety of cables exist within the SLSC ecosystem that allow you to appropriately split out and combine signal paths.

An example system diagram of SLSC components and their interface with a PXI DAQ card

 

The Growing SLSC Ecosystem

NI brings automated test and automated measurement expertise from an array of industries. This broad expertise allows us to create technology like SLSC from our observations of cross-industry needs. However, you need products that are targeted to your specific application. That’s why SLSC, designed to be an open platform, is enhanced by modules created by NI, our partners, and you through our module development kit (MDK).

Our partners, like Bloomy who has created a MIL-STD-1553 module for SLSC, bring domain expertise that yield products that are specific to your industry and unique test needs.

Below is a list of products currently available for SLSC from NI and NI partners. Due to the complex nature of HIL systems, please contact us for assistance when reviewing the technology listed below. NI and our Alliance Partners are dedicated to ensuring your test requirements are met.

Core Components NI Part Number Vendor Description
NI SLSC-12001 784532-01 NI Chassis, 24 VDC
Module Dev Kit 785205-01 NI Module Development Kit

 

Modules NI Part Number Vendor Description
SLSC-12101 785204-01 NI Prototyping Module
SLSC-12201 785356-01 NI 33V DIO Module with Thresholding
SLSC-12251 784444-01 NI 16 Ch 8A Fault Insertion Module
SLSC-12252 786445-01 NI 8 Ch 30A Fault Insertion Module
SET-1320 785671-01 SET 32 Ch Optical Isolated Output
SET-2010 786433-01 SET Routing Base Module
SET-2210 786434-01 SET Routing Instrument Connect Daughter Module
SET-2310 786435-01 SET Routing Line Fault Daughter Module
SET-1310 Available through partner SET 32 Ch Isolated Input
SET-1210 Available through partner SET Resistor Simulator Card
SET-141x Available through partner SET Modular Card
SET-1623 Available through partner SET 32 Ch ARINC TX/RX
SET-2315 Available through partner SET Real-time fault module
SET-1215 Available through partner SET High Precision Resistance Thermometer Simulator (PT100/PT1000)
SET-1220 Available through partner SET Capacitive Fuel Sensor Emulation
SET-1240 Available through partner SET xVDT Emulator
SET-1250 Available through partner SET 32 Channel 4-20mA Current Sink
SET-2090 Available through partner SET 32 Channel Pass Through Card
SET-1640 Available through partner SET PS15 Sensor Interface Card
Bloomy SLSC VDT/Resolver Simulation Module Available through partner Bloomy VDT Conditioning
Bloomy Thermocouple Simulator Available through partner Bloomy Thermocouple Simulation
Bloomy Load Module Available through partner Bloomy Load Measurements
Bloomy Multipurpose Module Available through partner Bloomy Multipurpose module
AL-1010 Available through partner Aliaro Multifunction Module for Automotive
AL-2010 Available through partner Aliaro

CAN/LIN/Ethernet Bus Switch Board

AL-3010 Available through partner Aliaro Resistor Emulation Board
ALMA-10201 786924-01 ALMA 2 Channel Oxygen Sensor Simulation
ALMA-10401 786925-01 ALMA 4 Channel Oxygen Sensor Simulation
OP8901 Available through Partner OPAL-RT 32-Channel High-Speed Digital I/O Conditioning Board with FIU
OP8920 Available through Partner OPAL-RT 32-Channel Isolated Digital I/O Conditioning Board with FIU
OP8930 Available through Partner OPAL-RT 16-Channel Analog I/O Conditioning Board with FIU
OP8940  Available through Partner OPAL-RT

32-Channel Pass-Through with FIU Board

 

Rear Transition Interfaces* NI Part Number Vendor Description
RTI-12301B 786330-01 NI RTI DIO 32 for SHC68-C68-RDIO2
RTI-12302 785377-01 NI 64 Ch for RDIO2
RTI-12303 785375-01 NI DIO/AO/AI X 4 Bank Nanofit
RTI-12304 785374-01 NI DIO 37DSub
RTI-12344 785376-01 NI AO 37DSub
RTI-12305 785896-01 NI HD44 Connector


*See module user manuals for RTI recommendations.

 

Cables* NI Part Number Vendor Description
SHC68-C68-RDIO2 156166-01 NI 1 meter
SHC68-C68-RDIO2 156166-02 NI 2 meter
SH37F-37M-1 778621-01 NI 37-pin Female to Male Shielded I/O Cable, 1 meter
SH37F-37M-2 778621-02 NI 37-Pin Female to Male Shielded I/O Cable, 2 meter


*See module user manuals for cable recommendations.

 

Accessory NI Part Number Vendor Description
Front Panel Filler Kit 785206-01 NI 4 count
Rear Panel Filler Kit 785207-01 NI 4 count
Filter Replacement Kit 785208-01 NI N/A
Fan Replacement Kit 785218-01 NI N/A
Power Connector 785219-01 NI 5 count
RTI Strain Relief 785999-01 NI 5 count

 

While NI and our partners are developing and releasing modules we feel will be widely used, we know that there are specific requirements that are unique to your test system. To address these needs, our partners can design and deliver a test system based on NI’s platform that is tailored to your unique test demands.786924-01