Intepro and Pickering Interfaces’ close collaboration and shared belief in open architecture hardware is producing great results, and end customers are benefitting from the prompt delivery of fit-for-purpose ATE systems that are adaptable and scalable.
Established in 1981, Intepro supplies automated test equipment (ATE) to manufacturers of power electronics assemblies and is active in sectors that include aerospace, defense, automotive, medical, telecommunications, and renewable energy.
The company has a global customer base that includes some of the biggest names in their fields but is itself a relatively small company, with a headcount of just 25 people based in Ireland, the UK, and the USA. Disciplines within Intepro include electrical, mechanical, and software engineering.
“We’re a small but extremely efficient company,” comments Gerard Sheehan, Intepro’s Managing Director. “We know how to maximize the skills and resources we have in-house, and we believe in partnering with other specialists to create optimum solutions for our customers that meet their immediate needs, and which also support expansion.”
Intepro’s defense sector customers include Raytheon, Lockheed Martin, MBDA, BAE Systems, Crane Aerospace & Electronics, and the UK Ministry of Defence. In most cases, these companies have been customers for decades and have multiple complex ATEs (like the one shown in Figure 1) in use that were designed, manufactured, and installed by Intepro.
Figure 1 – Above, one of Intepro’s more complex ATEs.
Assemblies being tested include power supplies and converters, auxiliary power units (APUs), DC power sources, battery backup systems, inverters, chargers, and AC to DC converters. In addition, the electrification taking place in aerospace and other sectors – such as automotive and rail – is requiring the increased use of power assemblies, in turn increasing the demand for ATE systems.
Intepro also supplies ATE systems to a number of traditional PSU manufacturers, including Lambda and TDK.
These and other volume manufacturers tend to order a number of identical ATE systems from Intepro. For example, one customer recently bought three systems. One is in the customer’s design lab and the other two are on the production floor. If a new test needs to be developed, it can be done in the design lab without disrupting production. Similarly, anomalous test results found in production can be investigated offline in the lab
A Blend of Open and Custom
Intepro favors the use of open-architecture hardware and software in its systems because they afford great flexibility when it comes to sourcing components and drivers. Integration with off-the-shelf instrumentation is easier, too, not only for Intepro when developing the ATE but also for customers should they wish to add to their systems.
Core to Intepro’s open-architecture philosophy is the use of Ethernet-based LXI, PC-based-PXI, and popular interconnect standards, including CAN bus, GPIB, USB, and serial buses such as RS-232 and RS-485.
Intepro’s ATE systems also include a variety of programmable electronic sources, loads, and switching matrices. Many of these are supplied by electronic test and verification specialist Pickering Interfaces.
The relationship between the two companies dates back more than 30 years, to a time when Intepro designed and built its own scanning matrix cards (switch matrices) and bought reed relays from Pickering Electronics. With the advent of PXI and, latterly, PXIe (based on PCI and PCIe buses, respectively) and LXI, Pickering Interfaces entered the market with commercial off-the-shelf (COTS) modules for not only switching signals but also simulating electrical loads and providing voltage and current sources.
“It was a logical course of action for us to start buying COTS modules from Pickering Interfaces,” recalls Sheehan. “We recognized early on that Pickering is an expert in the field of test, measurement, and simulation, plus they have fully embraced open architecture hardware and software. They align perfectly with our beliefs and business model.”
Accordingly, many of the ATE systems Intepro has built during recent decades include at least one Pickering chassis (typically LXI—see Figure 2) and multiple cards, such as switch matrices, high-frequency test cards, voltage and current sources, power relay modules, and digital I/O cards.
Figure 2 – LXI chassis are at heart of many ATE Systems Intepro designs and builds
The Process
Most customers approach Intepro because they need to test the subcomponents of a power assembly they have designed and are manufacturing. For example, the assembly might be a PSU that accepts three-phase AC as an input and outputs DC at a number of different voltages, each rated to a specific (maximum permissible) current.
The PSU will likely contain a few power modules and a controller module. Each module will need to be tested independently. When it is proven that they all work to spec, the PSU will be assembled and tested as a whole.
Sheehan explains that test requirements tend to be the starting point of most Intepro projects, as they govern which sources must be supplied (e.g., AC, DC or both, with associated voltage, current and power levels), which loads must be applied (e.g., impedances, voltage, current and power levels), and what needs to be measured (e.g., voltages, currents, power and timing measurements).
Understandably, customers in some sectors are unable to provide Intepro with little more than a broad wish list. However, Intepro will always work with the customer to spec’ a solution, one that includes the provision of a chassis, hardware, control software, and mechanical test fixture to physically interface with the unit under test.
The overall solution will also typically include a variety of fully integrated instruments, such as oscilloscopes, digital volt meters, and function generators. Data collection and interpretation are also factored into the design, and Intepro works with its customers to agree on the parameters to be measured and what constitutes a Pass or a Fail for any given test. In the majority of cases, Intepro then writes the software to fully automate the ATE.
Despite the scope of some projects, customers are typically looking at a project turnaround time of between three to nine months. The longer timeframe tends to be because more time (up to few months) might be spent agreeing specifications, creating schematics, and producing a bill of materials. Also, some parts might have long (two- or three-month) lead times.
Chassis & Modules
A very popular chassis with Intepro is Pickering’s 18-slot 3U LXI/USB modular switching chassis (see Figure 3). It is fully compliant with the LXI Standard 1.4 and accommodates up to 18 3U PXI modules that can be independently controlled through a standardized Ethernet or USB interface, i.e., each module is an addressable LXI-compliant device. The modules can also be controlled through a kernel driver.
Figure 3 – Pickering’s LXI/USB 18-Slot Modular Chassis
As for modules, the 40-320A-101 (see Figure 4) is a firm favorite. It is a single 24-channel multiplexer and part of Pickering’s 40-310/320A range of high voltage switching modules. All modules in the range are supported by PXI and LXI chassis, and feature Pickering’s own high quality reed relays. These relays have operational times of less than 0.5ms and can hot switch up to 750VDC or 750VAC peak (up to 10W max power) and cold switch up to 1kVDC or 1kVAC peak.
Figure 4 – Part of Pickering’s 40-310/320A range, the 40-320A-101 (pictured) is ideal for applications that include circuit board isolation testing, relay testing, semiconductor breakdown monitoring and cable harness insulation testing.
Another of Intepro’s favorites is the 40-755-110 (see Figure 5), a high-density RF multiplexer. It is part of a range within which the multiplexers are available as 50 or 75Ω variants. Also, all in the range are available with two connector options; either SMB (shown in Figure 5) that provides a frequency range of 1.8GHz (50Ω) / 1.3 GHz (75Ω) or multiway which limits the bandwidth to 1.3 GHz but offers a high-density solution that occupies a single PXI slot. The modules are supported by PXI or LXI chassis.
Figure 5 – The 40-755-110 offers low insertion loss and low VSWR through its usable frequency range and each multiplexer has been designed to have path independent loss.
“We try and standardize on certain generic Pickering modules that work across multiple platforms,” notes Sheehan. “So, when we build a new system, they will be our go-to modules because we have already written software to control them. This minimizes development time for us and keeps costs low for the customer.”
Futureproofing
Intepro’s approach to not only open architecture but also keeping as much as possible generic provides a high degree of hardware abstraction. Specifically, the way the company constructs its software means that if, for example, one DC source needs to be switched out and another used in its place, it is only a case of switching configuration files and the control software will work as before. Moreover, there is seldom a need for a customer to revalidate the system from either an engineering or a QA perspective. And this is one of Intepro’s big selling features: that the systems are so easily adaptable.
Another aspect of futureproofing is not being caught out by obsolescence. Sheehan goes on to say that another benefit of partnering with Pickering and using its COTS products is that component obsolescence is managed.
“It’s just one less headache for us,” says Sheehan. “We’re happy to standardize on some Pickering modules, safe in the knowledge that if they [Pickering Interfaces] have to replace some components because the original ones have become obsolete, we’re immune. At the end of the day, we’re buying functionality. And that’s what our customers are buying from us.”
Versatility is important, too, and Sheehan says that, following discussions to thoroughly understand both technical and business/commercial objectives, one customer has recently been supplied with a test station capable of testing 31 different products. The customer need only change the test fixture.
Conclusion
By leveraging open architecture hardware and software, Pickering Interfaces and Intepro’s close collaboration is delivering easy-to-integrate, scalable, adaptable, and future-proofed ATE systems that meet the complex (and often volume) test requirements of end users in a variety of industry sectors. These customers are benefitting from cost-effective and robust solutions – delivered within a relatively short timeframe, considering the complexity of some systems – that not only meet their current requirements, but which also support future modifications and expansion.
Reproduced here by the kind permission of Pickering Interfaces.