What parameters can CPFE1000Fi power supplies provide via I2C?

TDK-Lambda’s CPFE1000FI conduction cooled AC-DC power supplies feature an I2C interface as standard. This video explains what can be monitored, including baseplate temperature and status signals. The interface allows the units to be operated and monitored remotely.

Click here to read more about the full range of AC-DC power supplies, or click here for the product page: www.uk.tdk-lambda.com/cpfei

If you have a question you’d like to ask TDK-Lambda, please feel free to use the online FAQ form and we’ll get back to you with an answer to your question as soon as possible.


What are the key features of CPFE1000FI conduction cooled power supplies?

The CPFE1000FI series of conduction cooled power supplies can deliver up to 1000W and are based on the TDK-Lambda’s popular PFE1000F AC-DC power modules. This video demonstrates the key features and available options of the power supply, including board coating and three choices of mechanical configuration. Product specifications are reviewed, including the I2C communications interface, which allows remote monitoring.

Click here to read more about the full range of AC-DC power supplies, or click here for the product page: www.uk.tdk-lambda.com/cpfei

If you have a question you’d like to ask TDK-Lambda, please feel free to use the online FAQ form and we’ll get back to you with an answer to your question as soon as possible.


How to differentiate between power supply standby voltage and off-load power draw

Power supply standby voltage and off-load power draw are two terms that seem similar but are really quite different.

Standby Voltage
The use of a Standby Voltage on computer power supplies became widespread when the ATX specification was published in 1995. It enables a computer to be put into a low power consumption mode without fully powering down the processor, allowing a quick response when activated again. This was achieved by using a remote on/off signal to turn off the outputs, but still supplying a small amount of power to the processor from an independent voltage. This “Standby Voltage” is always present even if the main outputs are inhibited using the remote on/off.

Figure 1 shows a block diagram for a power supply like TDK-Lambda’s CUS350M, which features a main output, an auxiliary output (typically used for driving fans) and a standby voltage. A remote on/off is also provided.

Fig 1 - CUS350M block diagram
Figure 1: CUS350M power supply block diagram

The main and the auxiliary outputs use a common transformer and switching circuit. If the remote on/off is activated, both the main output and the auxiliary will turned off. As the V Standby output has an independent transformer and switching circuit, it will continue to operate. Figure 2 shows the timing diagram under the different conditions.

Fig 2 - timing diagram
Figure 2: Timing diagram

It can be seen that when the remote on/off (dark blue line) is pulled high, the 5V Standby (purple) continues to operate, but the main DC Output (green) drops until the remote on/off is pulled low again. Of course if the AC Input voltage (red) is removed for an extended period, then the 5V Standby will eventually fall.

Off-load power draw
With low power products (typically 150W or less), the off-load power draw is measured by removing the load and measuring the input power.

With products greater than 150W that have a remote on/off feature, often the off-load power draw is measured when the remote on/off is activated. This may be written in the specification as “Standby input power draw” or “remote off power draw”. Users who want a low off-load power draw must turn off the main converter using the remote on/off function.

It must be noted that if the power supply has a standby voltage, then that load must also be at zero when minimum off-load power draw is needed. If for example the standby is supplying 5V 0.25A (1.25W) and the remote on/off is applied, the standby output will continue to delivery 1.25W, making it impossible to achieve <0.5W input power draw!

For more information about the CUS350M power supply, please visit: www.uk.tdk-lambda.com/cus350m


What is the operating ambient and baseplate temperature of CPFE1000Fi power supplies?

The CPFE1000FI series of 700 to 1000W power supplies rely on conduction cooling to operate. This video from TDK-Lambda explains that the operating ambient temperature range is from -40 to 70oC. The maximum baseplate temperature is higher, at 85oC, where waste heat is transferred to either a cold-plate (liquid or air-cooled) or to an enclosure for outdoor applications.

Click here to read more about the full range of AC-DC power supplies, or click here for the product page: www.uk.tdk-lambda.com/cpfei

If you have a question you’d like to ask TDK-Lambda, please feel free to use the online FAQ form and we’ll get back to you with an answer to your question as soon as possible.


Industrial power supplies deliver 2500W in slim-line 1U high format

LA2882 - RFE2500 Series

TDK Corporation announces the introduction of the RFE2500 series of AC-DC power supplies. Rated at up to 2500W output power, the units are available in three output voltages, 12V, 24V and 48V. Featuring screw terminal and bus-bar connections, this very compact series does not require an additional plug-in rack or backplane making it ideal for space-constrained industrial, communications and test & measurement applications.

Operating from a wide-range input of 85 to 265Vac, the RFE series has operating efficiencies of 90 to 93% minimising internal heating and reducing power consumption. Up to 8 units can be connected in parallel for additional power or to provide a redundant power system. Internal ORing FETs and single wire current share are included as standard.

The units will operate in ambient temperatures of -10 to +70ºC with applicable derating above 50ºC. The outputs are adjustable by up to 20% using either the front panel trim pot, an external 0 – 5V signal or an external 1k potentiometer. The RFE is cooled by two internal temperature controlled fans to reduce acoustic noise at lower temperatures and loading conditions. Overall case dimensions are 107 x 41 x 345mm (W x H x D), and the weight is just 2.5kg.

As standard the RFE has AC Fail and DC Good signals, remote on/off, a 12V 0.5A auxiliary output, remote sense and LED indicator lights. An optional PMBus™ interface allows engineers to remotely monitor output voltage, output current and the internal ambient temperature in addition to status information. The output voltage, overcurrent limit and remote on/off can also be programmed.

The units are safety certified to IEC/EN/US 60950-1 with CE marking for the Low Voltage and RoHS2 Directives. They also comply with EN 55022-B conducted emissions (Class A radiated), and meet the EN 61000-3-2 harmonics and IEC 61000-4 immunity standards.

For more information about the full range of TDK-Lambda RFE2500 series of AC-DC power supplies, please call TDK-Lambda directly on +44 (0)1271 856600 or visit the TDK-Lambda website at: www.uk.tdk-lambda.com/rfe


Introducing the iJA 35A non-isolated SMT Point of Load with PMBus™

With PMBusTM compliance, the iJA series of non-isolated POL DC-DC converters provides excellent flexibility and the ability for customisation. Accepting an 8 to 14Vdc input, the product can deliver up to 35A with an adjustable output voltage of 0.6 to 3.3Vdc. Designed to drive CPUs, FPGAs and ASICs, these POLs feature digital adaptive control to accommodate a wide range of external load capacitance with great stability, even without the use of external loop components.

To watch the video, which introduces the iJA series, please click here.

Click here to read more about the full range of DC-DC converters, or click here for the product page: www.uk.tdk-lambda.com/ija

If you have a question you’d like to ask TDK-Lambda, please feel free to use the online FAQ form and we’ll get back to you with an answer to your question as soon as possible.


Testing Transportation Refrigeration Units


To ensure refrigeration reliability in transportation applications, each unit must be thoroughly tested to avoid expensive cargo losses. TDK-Lambda’s 5-year warranty RWS-B 600W power supply is used to supply the 12Vdc input needed during the test process by a producer of high quality refrigeration units. The /CO2 option was specified to help protect the power supply printed circuit boards from ingress of any contaminants. Also, the customer preferred the additional protection the RWS600B galvanized sheet metal provided against corrosion. Local support and relationship also helped win the opportunity.



Satellite Communications


For remote or offshore locations, satellite communication is an ideal and reliable way to transfer data and connect facilities or equipment together. Transmission channel up-time is enhanced as third party infrastructure is avoided. A provider of satellite communications designed in TDK-Lambda’s iQE series of 12V output DC-DC converters. The wide-range 18 – 60V input version was used to allow operation with either 24V or 48V battery back-up. The 5-year warranty RWS150B AC-DC power supply is also being used where DC input is not required. Support was provided throughout the project by the local sales team.



Integrated Process Plant Telecommunication Systems


Telecom equipment is often isolated from the manufacturing process plant control system. The revolution of Industry 4.0 is changing the way goods are built and processed, requiring full integration of all the communication networks. A major provider of process control integrated systems is using TDK-Lambda’s iEA high efficiency DC-DC converter to deliver 28V power with minimal airflow. Local support was welcomed by the customer during the development.



DNV GL and how this applies to power supplies

Like UL (Underwriter’s Laboratories), DNV GL’s heritage stems from insurance. DNV and GL were originally formed in 1860s to evaluate the quality of ships. That has since been expanded to include the vast array of electronics systems now used in maritime on/offshore applications.

Power supplies are used extensively to provide regulated voltages to drive motors, relays and power those electronic systems. Most manufacturers of power supplies are already familiar with getting IEC 60950-1 certification for use in information technology equipment. DNV GL certification, or Type Approval as it is referred to, has some differences:
An audit is carried out at the manufacturer’s factory, similar to that for ISO9001, which is valid for five years. Follow up visits are made after that.

Product assessment is made to the test standard “Guidelines for the Performance of Type Approvals – Test Requirements for Electrical / Electronic Equipment and Systems (VI-7-2)”. This report format is similar to that of an IEC 60950-1 CB report, and includes conducted and radiated EMC results.

Two levels of approval are possible which determines the type of application the power supply can be used in: Zone 1 – Bridge and open deck and Zone 2 – General power distribution. The limits on radiated emissions and conducted emissions are different to EN 55022, with Zone 1 more stringent.

DNV - image1

Immunity tests are performed using IEC 61000-4 as a basis.

Products also are defined to environmental categories A through H which states operating conditions like temperature, humidity and vibration.

Upon successful completion of the tests, the power supply can then be labelled with the GL Mark.

DNV - image2

A power supply like TDK-Lambda’s DRF/HL series of 120W to 480W DIN Rail power supplies which is approved to Environmental Category C, Zone 2, could be used in a Zone 1 application provided it is mounted in a minimum IP54 rated enclosure with an additional input filter. Coated printed circuit boards in the DRF/HL provide additional protection against moisture.
The DRF/HL series is also ATEX and IEC Ex certified for explosive atmospheres, certified to IEC 60950-1 and is backed by a five year warranty.