Category Archive: Power Supply

Tips to Keep in Mind When Selecting an AC-DC Open-frame Power Supply

Cincon - AC-DC Open-frame Power Supply
Sager Power Systems, a specialized group of Sager Electronics, offers a dedicated sales force of power systems sales engineers concentrated on power, thermal management and battery solutions with the unique position of providing traditional distribution services and value-added design. Sager is focused on bringing our customers the newest products, technical design information and design support to support our customers’ application requirements.

Choosing the Right PSU Matters

AC-DC power supplies are essential in many end applications as major power supply units (PSUs). More and more, power supply manufacturers provide a wide variety of options to engineers. While some PSUs may be suitable to your device, others may not due to the design of the PSU. Therefore, selecting the right PSU for your specific requirement is an important factor in the success of your project.

  1. Class I or Class II for your system
  2. Heat dissipation to the power supply

Class I or Class II for Your Application?

The PSU is the key component in making your device work. The first thing to determine is if your end application has a ground (earth) connection.

If the system design of the device includes a ground connection, a Class I power supply is the correct choice. If the design does not include a ground connection, a Class II power supply is the best option. The EMC testing result is deeply affected by the choice of the power supply, making it a critical factor during the selection process.

In many cases, when an end application is a portable device, it’s common for a Class II power supply to be selected. The reason for choosing a Class II power supply is due to the increased uncertainty surrounding the AC power source in these types of devices; there is limited knowledge of the AC source’s connection with the ground. In other cases, Class I power supplies are chosen.

For the user’s convenience, unlike many power supplies which only have one version, Cincon also developed several series which can be used as either Class I or Class II with more options under development.

Protecting Patients from Potential Electrical Failure

Sager Power Systems, a specialized group of Sager Electronics, offers a dedicated sales force of power systems sales engineers concentrated on power, thermal management and battery solutions with the unique position of providing traditional distribution services and value-added Contact Sager Power Systemsdesign. Sager is focused on bringing our customers the newest products, technical design information and design expertise to support our customers’ application requirements.

As part of our education series, TRACO Power’s Florian Haas delves into the safety concerns that must be considered when a patient is connected to an electrically powered medical device, and how to best protect that patient by avoiding electrical failure.

People and power don’t mix well, and this is particularly true when people are medical patients. Aside from the more usual environment of a medical facility, patients are also increasingly using medical devices at home. Medical equipment is therefore heavily regulated by standards-based requirements and subsequent product testing to ensure the safety of patients and healthcare professionals alike.

Medical equipment with Power Supply & DC/DC Converter
The most pressing safety concern related to medical devices comes into play when the patient is physically connected to an electrically powered device, such as the conductive pads of an electrocardiograph. These are defined as applied parts (AP). The route to ensuring patient safety lies in the implementation of IEC 60601, “Medical electrical equipment,” the standard central to the safety of electronic and electrical medical equipment power supplies.

Understanding Key Definitions

To safeguard patients connected to an AP medical device, IEC 60601 dictates that all medical devices must contain at least one means of protection (MOP), which could include insulation, earthing systems, air gaps, minimum creepage distances, or other protective electrical impedances.

Since the release of the third edition, the standard makes a clear distinction between equipment that is designed to be used by operators and equipment that may come into contact with patients. Different levels of protection are required, defined as Means of Operator Protection (MOOP) and Means of Patient Protection (MOPP), respectively. MOPP regulations are the stricter of the two because of the additional risk that a patient might be unconscious when an electrical fault occurs. In addition, more than one MOP may sometimes be required in case one fails.

Traco Power
There are three classifications for AP devices: cardiac floating (CF) for conductive devices that could come into direct contact with the patient’s heart; body floating (BF) for conductive devices that may have prolonged contact with the patient’s body; and lastly body (B) for devices that are not normally conductive and can immediately be released from the body. Types CF and BF require a minimum of 2 x MOPPs.

Protecting Devices Against EMI

IEC 60601 has evolved over the past 40 years to keep up with advancements in technology. With wireless communication technology becoming more abundant in hospitals and homes, there is a need for these sensitive circuits to be impervious to electromagnetic interference (EMI). The fourth edition of the standard has, therefore, now increased the acceptance levels for electromagnetic compatibility (EMC).

TRACO Power TPP450 Series

Risk Reduction and QMS

Two significant new introductions to the standard have been the requirements for the manufacturers of medical devices to undertake risk assessments, which must be undertaken in compliance with ISO 14971, “Medical devices – Application of risk management to medical devices,” to define best practice throughout the entire life cycle of an AP medical device.

Component manufacturers must also implement an ISO 13485 compliant quality management system (QMS) to demonstrate their ability to consistently meet both customer and regulatory requirements.

Practical Tips for Meeting the Standards

For AP medical devices to meet IEC 60601, the first step would usually be to select a medically approved AC/DC supply. Many designers will specify a power supply with 2 x MOPPs to simplify the qualification process and risk assessment, even if the highest level of protection is not actually required for the device’s application.

The most pressing safety concern related to medical devices comes into play when the patient is physically connected to an electrically powered device, such as the conductive pads of an electrocardiograph. These are defined as applied parts (AP). The route to ensuring patient safety lies in the implementation of IEC 60601, “Medical electrical equipment,” the standard central to the safety of electronic and electrical medical equipment power supplies.

Traco Segment Medical

However, it can become challenging to source a medical-grade stand-alone AC/DC power supply with a BF-compliant 2 x MOPP rating, particularly when the DC voltages needed for the AP instrument are different to the main system DC voltage. In this case, a 2 x MOPP IEC 60601 DC/DC converter combined with an ITE 62368 rated AC/DC power supply can easily be used to obtain compliance instead of trying to source a custom AC/DC power supply for the task.

Specialized DC/DC converters are available that meet the standard 2 x MOPP requirements. With up to 5000 V AC of isolation, double insulation and 8 mm of creepage distance through its galvanically isolating transformer, a DC/DC converter can provide protection in the event of a mains failure (see Figure 1). By providing this, the DC/DC converter avoids mains voltage levels appearing at any patient AP points.

An important part of the protection lies in a low coupling capacitance between the primary and secondary transformer windings to ensure that there is negligible transfer of current across the isolation barrier. Traco Power, for example, offers both AC/DC and DC/DC solutions for medical applications, all of which fulfill the 2 x MOPP requirement. Compliant with the EMC requirements of IEC 60601-1 (4th edition), they are suitable for all patient-connected, AP medical devices (BF compliant). The AC/DC products range from small 5W PCB-mounting modules, to a range of mid-power open frame designs, and enclosed power supplies offering power levels of up to 850 W. The company’s medically approved DC/DC converters offer 5000 VAC rms of input-output isolation, rated for a 250 VAC rms working voltage. This, along with leakage currents below 2 μA, make them ideal choices for use in conjunction with non-approved AC/DC PSUs in safety-critical medical applications.


The healthcare market is growing rapidly and the applicable standards that govern medical products will no doubt continue to evolve to keep safety standards high. Understanding the differences between Means of Operator Protection (MOOP) and Means of Patient Protection (MOPP) is key to properly safeguarding patients. Protecting against EMI but also applying ISO 14971 can ensure that devices are safe when the patient is physically connected to an electrically powered device. Partnering with reliable and experienced power supply manufacturers such as TRACO can greatly simplify the process.This article was written by Florian Haas, Director of Marketing for TRACO Power Group, San Jose, CA.

As an authorized distributor of TRACO Power, Sager Power Systems is well positioned to support your medical design requirements. TRACO Power offers a wide selection of medical products, including their TPP Series of AC/DC power supplies and the THM series of DC/DC converters, all of which have medical approval, meet 2xMOPP and are BF Complaint. A Sager Power Systems Sales Engineer is ready to help you design-in one of these solutions:

Series Features & Benefits
  • Ultra wide 4:1 input voltage 3 W DC/DC converter in a compact DIP-24 plastic case
  • I/O isolation 5000 VACrms rated for 250 VACrms working voltage
  • Certification according to IEC/EN/ES 60601-1 3rd edition for 2xMOPP
  • Risk management process according to ISO 14971 including risk management file
  • Acceptance criteria for electronic assemblies according to IPC-A-610 Level 3
  • Low leakage current < 2µA
  • Extended operating temperature range -40°C to 90°C.
  • EMC compliance to IEC 60601-1-2 4th edition and EN55032 class A
  • Operating up to 5000m altitude
  • 5 year product warranty
THM 3 Traco Power
  • High power density 3″ x 5″ open frame medical power supply
  • 450 Watt with forced air cooling, up to 320 Watt convection cooled without derating up to 50°C
  • Medical certification to IEC/EN/ES 60601-1 3rd edition for 2 x MOPP
  • EMC compliance to IEC/EN 60601-1-2 4th edition
  • Risk management process according to ISO 14971 incl. risk management file
  • Acceptance criteria for electronic assemblies acc. to IPC-A-610 class 3
  • Isolation (4000 VAC) and leakage current (<100 µA) rated for BF applications
  • Standard features: 5 V standby output 12 V fan output, Remote On/Off, Power, Good Signal, variable fan speed
  • Operating up to 5000 m altitude
  • 5-year product warranty
 TRACO Power TPP450 Series
  • Compact DIP-16-package
  • Wide 2:1 input voltage
  • I/O isolation 5000 VACrms rated for 250 VACrms working voltage
  • Certification according to IEC/EN/ES 60601-1 3rd edition for 2xMOPP and operation to 5000 m altitude
  • Low leakage current < 2 µA for BF-applications
  • High efficiency up to 83%
  • Extended operating temperature range –40°C to 90°C.
  • MC compliance to IEC 60601-1-2 4th edition and EN55032 class A
  • 5-year product warranty
 TIM 3.5 Traco Power

Visit the TPP Series of AC/DC Power Supplies page for more information on this product offering.

Visit the THM Series of DC/DC Power Supplies page for more information on this product offering.

Visit the TRACO Power page on for more information on their offering or contact a Sager Power Systems representative, the authorized Distributor for TRACO Power, at (866) 588-1750, or through the below form:

Evaluating a Convection Cooled Power Supply’s Performance

Sager Power Systems, a specialized group of Sager Electronics, offers a dedicated sales force of power systems sales engineers concentrated on power, thermal management and battery solutions with the unique position of providing traditional distribution services and value-added design. Sager is focused on bringing our customers the newest products, technical design information and design support to support our customers’ application requirements.

The Power Guy at TDK-Lambda recently blogged on a subject worthy of mention: how to evaluate a convection cooled power supply’s performance. What makes this such an important topic of discussion is the variety of testing methods across the industry differ significantly.

Before jumping right into the topic at hand, the Power Guy recapped convection cooling as it is widely assumed a convection cooled power supply does not need any airflow to operate. One definition of convection is “The transfer of heat by the circulation or movement of the heated parts of a liquid or gas”. In our case – the circulation or movement of hot air.

An open frame power supply is typically mounted on a flat surface upon standoffs. Figure 1 shows how the air behaves. As the hot air rises, cooler air is drawn in from the sides. Although the airspeed is quite low, just 0.3m/s, it is sufficient to reduce internal temperatures..

Convection Cooled Power Supply
Evaluating a Convection Cooled Power Supply

Before making the choice of vendor and power supply it is advisable to download not only the datasheet, but also the manufacturer’s evaluation report, reliability data, application information and safety files for the “Conditions of Acceptability”. If it is not available from the website request it. This “homework” is paramount to ensuring you are not going to have program delays due to non-performing power supplies or worse, excessive field failures.
The report listing the thermal measurements is a key section and may raise some suspicions.

Most power supplies are capable of operating over a wide range input. From a thermal aspect 115Vac is tougher than 230Vac, due to the higher currents (I2 x R=losses) in the input filtering and rectification circuitry. If the report only states results measured at 230V, this may be an issue.

Convection cooled power supplies often have a higher forced air cooling rating stated on the datasheet. In this case the report should confirm if the test results were recorded with convection cooling. If that statement has not been made it should be noted for your own follow up testing. Check that the output loading is at 100%.

The mounting orientation affects the thermal performance of the power supply. This too should be identified in the report.

Where was the ambient temperature measured? Some reports show the temperature recorded above the power supply. This falsely overstates the true ambient temperature. Ambient should be recorded on both sides of the power supply, or underneath for a vertically mounted or DIN rail mounted supply.

At what ambient temperature were the measurements recorded at and how long was the power supply running before the tests took place?

A convection cooled power supply will take between two and three hours for the temperatures to stabilize. The larger, hotter components like the isolation transformer and power semiconductor heatsinks have a greater thermal mass than a small capacitor. If the report states that the power supply was run for one hour at 25oC and for one hour at 50oC then there should be at approximately a 20 oC delta between the two sets of results. Power semiconductors do operate more efficiently at higher case temperatures, and the natural convection airflow will be higher, so there will be some discrepancies. This is why extrapolating results can give errors due to non-linearity.

Having received your sample power supplies, you can start testing. If a thermal chamber is not readily available, it is advisable to bench test with the unit covered with a large enclosure. This avoids external airflow from air-conditioning systems affecting the results. Even in a thermal chamber, there may be an internal fan to circulate air. TDK-Lambda recommends placing the power supply in a sealed enclosure to shield that air from interfering with the results. Remember to test at all the input voltages your system will be operating from.
Ideally the temperature of each electrolytic capacitor should be measured using thermocouples attached to the exposed metal case at the top of the component. This data can be used to determine each capacitor’s life. TDK-Lambda can assist, supplying a sample with thermocouples already attached*.

In the end system it is very important to ensure that there is adequate space for the air to be drawn in from the sides and allowed to exit above the power supply. A distance of 50mm is considered safe, less than this will cause interference with the natural convection airflow. Power supply thermal testing has to be repeated again in the end system to verify the naturally circulating airflow has not been restricted.

The cooler a power supply operates, the longer it will last. Care taken during the early stages of product development can avoid last minute launch delays.
And that is where Sager can help. As an authorized distributor of TDK-Lambda convection cooled power supplies, Sager Power Systems is well positioned to support your design requirements. TDK-Lambda offers a wide selection of products to address these specific convection cooling needs including:


30W – 600W Switching Power Supply

  • 30W, 60W, 100W, 150W, 200W, 250W, 350W and 600W models
  • 5V to 48VDC output range
  • Suitable for Industrial & Medical applications
  • BF ready medical isolation (2 x MOPP)
  • Suitable for Class I and II installations
  • For high ambient temperatures up to 85°C (model dependent)
  • High efficiencies up to 94%
  • Operating Altitude up to 5000m
  • 3, 5 or 7 year warranty (model dependent)
  • IEC60335-1 compliant models available



CUS600M-19 TDK-Lambda Switching Power Supplies 600.4W 19V 31.6A Med

 600W Switching Power Supply

  • Convection Cooled
  • Up to 95% Efficient
  • RS-485 Read-Write Communication (Modbus RTU protocol)
  • Constant Voltage & Constant Current Modes
  • Medical and Industrial Certifications
  • Monitoring & Programming Functions
  • Digital or Analog Programming
  • Seven Year Warranty
 GXE600-24 TDK-Lambda Switching Power Supplies 600W 115-230AC input 24V out 25A Med

48V 480W DIN Rail Power Supply

  • 15W to 480W High Efficiency DIN Rail Mount Power Supplies
  • Excellent efficiency – up to 93%
  • ErP compliant
  • Very low no load power consumption
  • Market leading case widths
  • Output voltages 5, 12-15, 24, 48VDC
  • Single phase input
  • 15W, 30W, 50W, 100W 120W, 240W & 480W models
  • Class 1 Div 2 for Hazardous Locations (15-100W)
  • Class 2 Models to UL1310 (see selector guides)
  • 3 year warranty
  • Suitable for TS-35/7.5 and TS-35/15 DIN Rails
 TDK-Lambda DRB Series 48V 480W DIN Rail Power Supply in in stock at Sager

for more information on their offering, contact a Sager Power Systems representative, the authorized Distributor for TDK-Lambda, at (866) 588-1750 or complete the form below:

The Challenges of Designing and Sourcing Power Supplies and Batteries

Every electronic application requires some form of power source, but designing and sourcing power supplies and batteries can be challenging. Customers often face potentially complex solutions, long design cycles, extended lead times, and a lack of expert design guidance. Because power and power-related products are some of the most complex in terms of design and procurement, a number of key factors must be considered when designing power.  

Power Supplies

Engineers and purchasing professionals must weigh many factors including an understanding of the end application, including any portability requirement. Some of the questions to ask; What is the size, output power, efficiency, and reliability needed? How will heat be managed and what means of thermal management is required? For instance, should the power supply be fan-cooled, convection, or conduction cooled?  Are there safety concerns and at what level (e.g., Class 2 vs. Class II)? Is interference an issue and does the device require EMI/RFI filtering? How long will the device run and what are the peak power loads that are required? Does the application require an uninterruptible power source or a battery backup? 

A technical power supply distributor such as Sager Electronics through its specialized group Sager Power Systems is often the key in helping a customer address these types of design challenges. Sales engineers can assist customers in determining the correct power and battery backup solution. Recommendations may include several design options from off-the-shelf AC-DC power supplies and DC-Converters to modified standard products that range from simple modifications to highly complex design. 

Battery Backup

The power grids across the United States face major challenges due to infrastructure age, intense weather, and the increase in demand for electricity. Electrical outages, brownouts, and surges are a reality, and these factors need to be strongly considered when designing electronic systems.  This is especially so for equipment manufacturers in the industrial and medical sectors where down time can lead to major financial loss or potentially life-threatening situations. The growth of home health care devices like respirators, CPAP machines, power wheelchairs, and home dialysis equipment are essential to quality of life and independence, and these systems all require battery backup. To address the demand for portable and backup power requirements, Sager added RRC Power Solutions, a lithium-Ion smart battery pack manufacturer, and Power Sonic, a leader in sealed lead acid and lithium-Ion technology, to its line card.


Power sources tend to have a higher value and are often larger and weigh more than most components, impacting shipping methods and costs. Batteries also present some additional buying challenges specifically around shelf-life,  recycling considerations, and shipping and handling regulations. Lead times should be monitored as extensions on power supplies and batteries can present a challenge. Price, availability and handling make proper planning crucial in the procurement of power supplies and batteries.   

“The Sager Power Systems program is very unique to the marketplace. With a focus on power and synergistic technologies such as batteries and thermal management solutions, and the ability to provide best-in-class configurable and custom value-add services , no other distributor offers its customers this level of expertise in power and thermal,” explained Rich Arieta, Sager’s director of business development for Sager Power Systems. “Additionally, we can further support our customers’ requirements with a comprehensive array of supply chain services.”

In today’s quick and complex market, access to knowledgeable technical advice, breadth of quality product, and reliable service is paramount to successful design. 


Understanding the Complexities, Efficiency and safety Requirements of Power Supplies

The role of purchasing within an OEM or CEM is continuously expanding, and today’s purchasing professionals can heavily influence their company’s component selection. As influencers, their understanding of the parts they’re sourcing is critical to ensuring they make the right purchase at the right price and the right time. An educated buyer evaluates components, recognizes product quality requirements, and understands risk. This information is then used to make informed purchasing decisions. 


In the area of power supplies, these decisions may be made all the more challenging by the sheer nature of the product.  Design options are endless and may be more complex than other electronic components. Power supplies often have higher average selling prices (ASP) with long lead times, limited liability warranties, and stringent efficiency and safety requirements. Another consideration is the prevalence of power supplies amongst counterfeiters, and how easily a part may be sourced through unauthorized channels. With all of these challenges, what can a Purchasing professional do to source the best solution while protecting their company?


Understanding the complexities, efficiency and safety requirements of power supplies has a far-reaching, positive impact.  The best and easiest way to gain that understanding is to work with an authorized distributor that specializes in power conversion products.  This is even more critical as future power supplies will push the boundaries of technology, getting the most power into the smallest package while staying ahead of the latest safety and EMI/EMC requirements.  


An authorized distributor focused on power knows that by lowering the amount of wasted energy within the power supply, it runs coole- and aids in the thermal design of the overall system.  Less heat generated by the power supply allows the component size to be reduced or more power to be generated within the same package size.  For instance, not so long ago a 3”x5” power supply was designed to handle 40W of power.  Today, that same 3”x5” power supply can handle 250W with no airflow or up to 500W with air blowing across it. Standardizations in footprints (2”x3”, 2”x4”, 3”x5”, etc.), has allowed for more opportunities within the same footprint, but the number of options may be limitless. Having a resource to help guide purchasing through the buying process can save a lot of time, aggravation and money in the long-term.


Additionally, keeping up with changing standards is a constant challenge.  The international safety standards for power supplies, as well as end systems, are constantly being updated. EMI and EMC requirements are also changing based on new technology and how devices interact with each other.    The increase in electronic devices in our homes and businesses require more stringent requirements.  Electrostatic discharge (ESD) requirements have gone to higher levels to accommodate increased home use.  The susceptibility levels resulting from the presence of multiple electronic devices have also been raised to account for the proliferation of mobile phones, Wi-Fi networks, smarter appliances, and the internet of things (IoT) that are all connected wirelessly. The increase in medical devices for home healthcare brought about the need for additional safety standards as well. Authorized distribution works closely with power supply manufacturers to stay on top of these changes.


Sourcing smaller, more efficient, warrantied, and safe products, from an authorized power specialist like Sager Power Systems, a specialized group within Sager Electronics, will ultimately result in cost savings and an enhanced return on investment for a purchasing professional and their companies.


Knowledge is Power

When faced with a myriad of changing regulations, extended lead-times and tight delivery schedules, specialist expertise can provide powerful solutions, says Sager Electronics’ Paul Kopp

Q – What are the greatest challenges faced by the power sector?Paul Kopp

A) The ever-changing landscape of regulations is the biggest challenge, especially in medical, industrial and EMC-related applications, where regulations are frequently updated. Each country will have its own schedule for adopting industry certifications, so purchasers must be diligent in staying abreast of requirements. Manufacturers must also adapt materials and processes on an ongoing basis to ensure products meet the newest standards. Distribution plays a crucial role in tracking regulations and impacted parts across the supply chain. Sager works with both suppliers and customers to communicate changes, assist with new designs and stock the newest components, all while minimizing potential cost increases and delivery disruption.

Q – Have there been any major shifts in purchasing habits in the power sector?

A) For several years, we’ve seen a shift towards just in time deliveries from customers purchasing power conversion products. Power supplies have higher average selling prices and are physically larger than most components on a customer’s BOM, so purchasers can save money and production floorspace in this way. Increasingly, customers ask us to manage to their forecasts to make sure they have product available when required. We also work with purchasing and engineering to bridge any gaps between finding the best technical solution and sourcing components with the best price and lead-time. Customers are supported by a sales engineer and a field sales representative, while a dedicated inside sales representative manages price and delivery expectations.

Q – Have power supplies and associated products been affected by extending lead-times?

A) Lead-times of certain electronic components are beginning to extend, with pushouts of base products like capacitors, resistors, mosfets and FPGAs being felt across the supply chain. Power supplies rely on capacitive technology and are at an increased risk, but Sager has planned for any potential impact with significant investment in both high running items and customer specific parts. We’re confident we are well positioned to reduce the impact.

Q – How will readers benefit from Sager’s acquisition strategy?

A) The acquisition of PowerGate and Norvell, in 2014 and 2015 respectively, were designed to differentiate Sager Electronics through specialized knowledge, products and capabilities. Regional power supply distributor, PowerGate, was recognized for its technical sales team, marketing expertise and strong line card. Norvell furthered Sager’s value add capabilities, including full test, integration and design. In 2017, Sager acquired Power Sources Unlimited, which added to our technical expertise and enhanced relationships with shared power supply manufacturers. Today this technical team addresses front end inquiries from new customers, determining the right product solution.

Q – How does Sager prepare for the launch of a new power supply?

A)  Sager is given advanced notification of new product introduction and works closely with suppliers to profile and inventory products towards specific markets. We load descriptions, images and datasheets to support marketing efforts, which are communicated to customers through our News2Know email program. Our power sales engineering team also undergo training based on suppliers’ six to twelve-month product road map to provide customers with up-to-date product information.

Q – How does Sager’s inventory level compare now to three years ago?Authorized Distributor Structured to support both engineering and purchasing

A) We’ve increased our onhand inventory by over 30 per cent in the past three years. In the coming months, Sager will open a new 64,000 square foot power solutions center and distribution facility in Carrollton, Texas. Our new location is 70 per cent larger than our current center in that territory, allowing us to triple our existing distribution footprint.

Q – What advice would you give purchasers sourcing power supplies and associated products?

A) Power products are some of the most complex in terms of design and procurement, so work with an authorized distributor structured to support both engineering and purchasing; capitalize on the services, technical knowledge and breadth of product afforded by this relationship. Sager’s solutions such as vendor managed and bonded inventory, kitting and labelling, or power and thermal value-add capabilities, combined with a robust portfolio and dedicated technical specialists, help customers find the best fit for their requirement.

Off-board Power and Switch Challenges

Sourcing off-board power and switch components presents plenty of challenges in an industrial setting, as Sager Electronics’ vice president product marketing, electromechanical, Craig Sanderson, and director of supplier marketing, power products, Paul Kopp, explains

Off-board Power and Switch Challenges

Everyone involved in sourcing electronic components understands the intricacies of sourcing on-board components. Yet off-board components, although they may appear basic, have just as many variables and considerations, especially in industrial applications that require stringent regulatory compliance in potentially harsh environments.

Two key off-board components provide insight into these challenges: switches, which are one of the first components designed in; and power supplies, which are one of the most complex.

Today’s switch offering is more sophisticated than ever before. In addition to turning equipment on or off, switches may require sealing, LED illumination and wireless functionality. These considerations are even more complex when designing-in power supplies. At their most basic, power conversion products change currents or adjust voltage levels, but the variables are many and often a power supply architecture is required.

Technical Drivers

Technical Drivers

So, what does purchasing or engineering need to know to source the correct switch or power supply solution? In addition to electrical requirements, there are a few key considerations, not least of which is regulatory and standards compliance.

The regulatory environment has been dynamic over the past several years. Regulatory requirements such as UL, CSA, VDE, CCC as well as environmental standards such as RoHS, REACH, conflict mineral and others all play a role in sourcing the right components. In the power sector, one of the biggest changes occurred in early 2016 when Level VI energy efficiency requirements took effect.

It’s vital that OEMs continually track developments to ensure compliance and avoid costly delays or fines. Working through the distribution channel can ease the burden, since authorized distributors have their finger on the regulatory pulse and have close working relationships with the component manufacturers to help ensure compliance.

Ruggedization is another trend to consider, especially in the industrial sector where demand for robust, harsh-environment ready components has steadily increased. Considerations such as exposure to extreme temperatures, water and humidity, dust, vibrations and physical impact often come into play and it’s not uncommon to require IP67, IP68, or even the most stringent IP69 ratings.

Finally, miniaturization isn’t a new trend, but it continues to be pervasive across all components. Devices now require more power and increased functionality, while also fitting smaller footprints. Off-board components such as switches and power supplies must also meet these expectations.

Sourcing Switches

Sourcing Switches

The most common switches for industrial applications include limit, toggle, push button, oil-tight push button and basic or snap-action. Demand for sealed versions is generally higher in industrial applications, but there are also various other drivers at work in this segment.

Following the miniaturization trend, OEMs are looking for ways to pack more functionality into every component to create the most efficient footprint. Examples of this include circuit breakers used as switches and inline filters packaged together with a fuse and a power switch in a single device.

Physical appearance is another big driver regarding switch design. For example, a panel consisting of multiple switches, indicators, connectors and power supplies requires a uniform size so components fit together as a package. LED technology is also providing aesthetic opportunities, such as lit push button products. Unlike other components, however, switches have relatively few standard configurations and new switch designs are typically driven by specific OEM requirements.

Perhaps the most important consideration when selecting a switch is the degree to which the switch needs to support overall device safety. Some of the most common safety requirements include: heavy duty, high amperage; light duty, high current; harsh conditions and hazardous environments.

Pushing Power Boundaries

Sourcing power supplies is more complex than switches due to the number of variables, requirements and regulations. A lack of standard products and the need for complex solutions make sourcing power supplies a far bigger challenge for both purchasing and engineering.

All industrial electronic devices require power conversion using a power supply. This typically converts one type of electrical power to another, but may also convert a different form of energy such as solar into electrical energy. At the most elementary level, purchasers must first identify the type of power conversion required. For example, is a regulated or unregulated power supply best for the application? Does the application require AC to DC or DC to DC conversion, or does it require an external power supply? From there, the complexity and level of specification greatly increases.

When specifying a power supply, it is also important to understand the basic power requirements including: input voltage, wattage, number of outputs, voltages required, amperage and peak load.

After defining these requirements, there are other variables to consider. Think about the size, efficiency and reliability required. How will heat be managed, for example, and will the power supply be fan-cooled, convection, or conduction cooled? It may also be necessary to consider whether the supply will be used in a wet or damp location.

Other questions might focus on safety concerns, whether interference is an issue, or whether the device requires EMI/RFI filtering. Don’t forget to factor in how long the device will be running and what peak power loads will be required. Engineers must keep up with the latest power regulations and should consider whether the supply requires UL 60950, UL 508, CEC Level VI or UL 8750.

One final consideration in sourcing power supplies for industrial applications is the form factor. There are many different form factor options from open frame to enclosed, as well as encapsulated or PCB mount options. Other applications may call for an external adapter, or a Din rail or rack mount solution.

Supply Solutions

Supply Solutions

With so much to consider, a distributor like Sager Electronics and its specialized group, Sager Power Systems, can help by assisting with design, sourcing and supply chain services.

Sager believes the authorized distribution channel is the most efficient way for OEMs to source offboard components. Flexibility, ease of ordering and the ability to achieve economies by sourcing both on-board and off-board components from a single supplier are all hallmarks of distribution. Sager, for example, stocks a broad inventory of interconnect, power and electromechanical products while offering personalized services like bonded inventory programs, vendor managed inventory and bill of materials quotes to meet customer requirements.

As an authorized value-added reseller for its franchised suppliers, Sager also boasts quick turn assembly of modular power supplies. Value-added design and manufacturing services are offered through Sager’s power solutions center in Carrollton, Texas. From simple modifications to complex design, Sager’s team can guide a customer through the entire engineering process, including power supply selection, component sourcing, prototyping, test and manufacture.

Need a Custom Battery Pack? Know These 5 Critical Details First.

Reliable battery power is a critical piece in today’s portable world. Custom battery pack solutions across the medical, military, and industrial/commercial markets can vary widely.

Identifying the battery pack solution that will work best for your specific product is the tricky task.

Here are five key questions that you should be able to answer for your next battery product design:

1. What space is available for the battery power?

Do you have a sketch or drawing of the product you are building? Do you have dimensions of the space the battery should fit in?

Or are you early in your design process? Perhaps you still have flexibility on the form the battery pack needs to take.

This is a critical piece to plan for.

2. How long do you need your device to operate between charges?

This information is important because it indicates how much capacity (Ah) is needed when choosing a cell size and chemistry. One significant limitation, even a trade-off, is the space that is available for the battery.

3. What agency testing will be required?

The agency testing that is required will depend on the type of device and the market for which you’re building. The design of the custom battery pack inside your device may all or in part depend on the agency testing needed.

For instance, the drop test required for IEC 62133 will likely mean that the battery will need to be in a plastic case or at least protected with foam bumpers.

Some frequently required agency tests are: UL 2054, IEC 62133, and as well those referenced in the UN Manual of Tests and Criteria 38.3.

This can be a challenging aspect of the battery design process. We will work with you to verify the testing that is needed, and modify and evolve your battery design to successfully meet the requirements.

4. What battery chemistry is under consideration?

Do you already have product design requirements that justify using a particular chemistry for the battery? The chemistry of the battery will determine the functionality with regard to weight, form factor, capacity, voltage, energy density, and more.

We work with a wide variety of chemistries including:

  • Sealed Lead Acid (2v/cell)
  • Nickel Cadmium (1.2v/cell)
  • Nickel Metal Hydride (1.2v/cell)
  • Li-Ion derivatives including Cobalt Oxide (3.7v/cell), Nickel Manganese Cobalt (3.6V/cell), Nickel Cobalt Aluminum (3.6v/cell), Lithium Iron Phosphate (3.2V/cell), and Lithium Titanate (2.4v/cell)

5. What conditions will the device and battery pack be subjected to on a daily basis?

You’ll want to consider four areas (if not more) that might affect the device and/or battery:

  • Operating and storage temperature of the product
  • Continuous, average and peak discharge currents
  • Operating voltage range of the battery and device
  • Battery charger rate and method of charging

The answers to these will vary, but they can be incredibly helpful to getting the proper start on your custom battery pack design.

The right provider will be asking you these key questions upfront. You will save time, error, and ultimately cost in the long run by knowing as much about your requirements as you can early on.

If you have flexibility in your design, one of our off-the-shelf battery designs may save you time and money.

Or you can click here to request a quote for your specific project.