Archive

Browsing

What is an Original Equipment Manufacturer (OEM)? The term Original Equipment Manufacturer (OEM) originally referred to a company that supplied equipment to another company to resell or incorporate into their own equipment for sale. OEM is now used to refer to a product that is acquired by the company to be reused or incorporated into another product using the reseller’s brand name. Sometimes, OEM is used to refer to a company that makes the end product using parts from another manufacturer. The OEM is the company that makes subsystems or parts that are used by other companies to make the end product. An example is the Acme Manufacturing Company that makes power cables that are used in Dell computers; in this case Acme manufacturing Co. is the OEM. How OEMs Work Initially, OEM was applicable to business to business sales, where component manufacturers could only sell to the equipment manufacturers.…

What is switch mode power supply? A switch mode power supply is a power converter that utilises switching devices such as MOSFETs that continuously turn on and off at high frequency; and energy storage devices such as the capacitors and inductors to supply power during the non-conduction state of the switching device. The supplies have higher efficiencies of up to 90 %, are small in size and widely used in computers and other sensitive electronic equipment. The basic switch mode power supplies (SMPS) are categorized based on supply input and output voltage. The main four groups are: AC to DC – Off-line DC power supply DC to DC – Converter DC to AC – Inverter AC to AC – Cycloconverter of frequency changer SMPS topologies The circuit configuration, referred to as topology determines how the power is transferred from the input to the output. Most topologies consist of a power…

The MR16 is a multifaceted reflector bulbs, compatible for lighting fittings from track lights to pendant fixtures and suitable for a wide variety of applications including commercial and domestic. Originally designed as an halogen, this style of bulb is now also available in compact fluorescent and LED formats. MR16 MR16 LED light bulbs will function with the majority of standard low voltage MR16 LED drivers however some are typically 20~60VA which can cause problems for this lamp due to the transformer minimum load requirements not being met. Compared to halogen bulbs the LED MR16 bulbs draw a significantly smaller amount of power, therefore do not provide a sufficient load for the more traditional Halogen low wattage MR16 transformers. Choosing the right kind of MR16 LED transformer is an investment for your MR16 LED bulbs to ensure maximum lifespan and perfect operation. If the incorrect MR16 transformer is selected it can…

Introduction to Linear Power SuppliesLinear power supplies regulate the output voltage by dissipating excess power in the form of heat. Linear power supplies are ideal for those applications that require a very low noise power supply. The linear power supply uses a low frequency transformer composing of a core made of a silicon steel sheet to convert AC mains to a desired voltage; the power supply rectifies and filters the voltage to a DC level. Since general equipment requires a stable DC voltage, the rectified and filtered DC level should be regulated through a power regulator. The power regulator clamps excessive voltage at the predetermined level and dissipates unwanted voltage in the form of heat. View Sunpower’s linear power supply range

LED lighting offers users an efficient, safe and reliable lighting power solution. LED’s are fast becoming the prefered lighting choice of so many applcations because you get more light per watt, have the ability to turn on/off quickly, there are more colour options and they have a long lifespan. To meet this demand an increasing range of LED lighting power supplies is now available on the market. Sunpower UK’s lighting power supply range varies in size and capacity helping you get the right power supply for your application. Whether you are looking for a internal light fitting solution or a weatherproof solution capable of powering long strings of lights we have a LED lighting power supplies solution to suit. LED Lighting System Designs Setting Circuit Diagram Description Advantages & Disadvantages Constant Current mode Power Supplies No need for a ballast resistor and LED driver IC For 1W LED, VF=3.2V, I…

LED lighting is the preferred lighting choice for many applications due to its versatility, energy efficient design, crisp light and instant start up. Numerous lighting applications use intelligent design systems which require a dimming function. To meet this demand Sunpower has created an extensive range of LED dimmable power supplies, offering a range of dimming techniques. The LED dimmable power supply range from Sunpower offers the following dimming functions; 3-in-1 dimming – This is a combination of 1~10Vdc, PWM and resistive dimming. 1~10Vdc dimming– 1~10V source is applied to the driver, 1V control voltage approximates to 10% output voltage. PWM Signal dimming– PWM also known as pulse width modulation, this is an external circuit used to control the average voltage to the dimming input. Resistive dimming– 100K potentiometer, this does not require an external voltage as it uses a variable resistance across the internal control voltage from a driver. The…

DIN Rails are metal strips that provide a convenient means for mounting electric and electronic devices in a compact and neat manner. For example, DIN Rails are frequently used for mounting circuit breakers , terminal strips , power supplies and all sorts of industrial control equipment within racks/enclosures or attached to backboards. In this way, any combination of devices can be mounted next to each other to meet the system requirements. Standard DIN rails are shaped as shown below. They typically measure 35mm from edge to edge. The distance from the back to the rail of the front bends can be either 7.5mm or 15mm. These metal DIN Rail strips can be purchased in any length to suit the application and multiple rows of rails can be used. The use of DIN Rail mounting systems saves installation time since all devices just snap onto the metal rails. A complete system…

What is Warm-Up Drift? The initial change in output voltage of a power supply from turn-on until it reaches thermal equilibrium at nominal line, full load, and ambient temperature. Power supplies take time to stabilize their outputs. After the warm up, the power supply output reaches its specified stability. And even though the supply is capable of working immediately it is turned on, it is necessary to wait for it to stabilize if it powers a sensitive load that requires a very stable supply. Allowing the supply to warm up will therefore give it time to reach its thermal equilibrium and stabilize the output. The warm-up drift measures the change in the output of a power supply that results from the initial warming of the components over certain period. This measurement is carried out by turning the supply at its rated full load and then determining the output after the…

What is Voltage Balance? The voltage balance is the difference in magnitudes, in percent, of two output voltages that have equal nominal voltage magnitudes but opposite polarities. The voltage balance is usually used when referring to dual power supplies. This is the difference, between in magnitude of the positive and negative output voltages and as a percentage. Ideally, the value should be zero, but this is barely practical in most of the supplies. Supposing a dual power supply has a positive 12 V output on one end and a negative 12.12V on the other output. The voltage balance, in this case, will be given by {(12.12-12.00)/12} x 100 % which is equal to one percent. A balanced power has symmetrical voltages, equal but different polarity. These are used in powering audio amplifiers, dual supply operation amplifiers, come computer circuits etc. The dual supplies are sometimes used to power analog ICs…

What is an Uninterruptible Power Supply? An Uninterruptible Power Supply (UPS) is an electrical power supply that supplies electricity a load when the mains is available as well as when there is a mains power outage. The UPS protects the loads from power failures, and interruptions such as low-, or over- voltages. The UPS takes in AC power, stores part of the energy in a backup storage such as a battery or flywheel arrangement while the transferring the rest to the load. In the event of a power failure, the UPS uses the stored energy to supply the load hence allowing one to save work and have perform a proper shutdown of the computer of any other load. All UPSs have an audible alarm that warns the user that the mains power has gone off. Main parts of a UPS There are four main blocks in majority of the UPSs.…