Importance Of RoHS For Medical Isolation Transformers – Miracle Electronics

The term “medical” in itself indicates safety and caution. Medical transformers thus also need to be very carefully designed so as to keep both the operators and patients safe while they’re around the device. 

And, this is the reason why the transformers used in medical applications are always isolation transformers – those that isolate the patient and operator from electric shock, and protect the equipment from power surges and other faults. Such medical grade isolation transformers  thus need to maintain strict adherence to certain crucial standards; one of them being RoHS.

What is RoHS?

RoHS, or the Restriction on the use of Hazardous Substances, in itself states that no kind of hazardous substances are permitted to be used while manufacturing the particular device. The main goal of RoHS is to reduce the environmental effect and health impact of electronic equipment, by making electronics manufacturing safe at every stage of the electronic device’s life cycle.

When was RoHS introduced?

The RoHS restriction originated in the European Union in 2002, restricting the use of 6 particular hazardous substances found in electrical and electronic equipment. It was then officially adopted in February 2003. In 2005, on the 21^st of October, the European Commission decided to exempt the use of Cadmium and its compounds in electrical contacts. The next year, the European community established July 1 as the phase-out date for hazardous material in electronic products.

Why was RoHS introduced?

A wide range of materials were used to manufacture electrical and electronic equipment, such as radium, lead-tin allow, etc. But these materials, despite of the fact that the had many useful properties, were also discovered to be hazardous to both humans and the environment. It was thus a must to stop the usage of such harmful materials. For strict adherence, the RoHS was introduced, in order to improve the welfare of consumers, manufacturers, distributors, and the environment.

Which materials are restricted for use under the RoHS restriction?

As per the RoHS, products compliant with the derivative must not exceed the allowable amounts of the restricted materials (with some limited exemptions). The 6 restricted materials include lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls, and polybrominated diphenyl ethers. This derivative applied to manufacturers, importers, distributors, and authorized representatives of a wide array of products. Some of the most common products that need to adhere to the RoHS standard include small and large household appliances, consumer electronics, lighting, computing equipment, communication equipment, power tools, and not to forget – medial transformers.

Why is it a must to adhere to the RoHS standard?

The 6 materials that fall under the RoHS derivative are hazardous to the environment, and also dangerous in terms of occupational exposure during manufacturing and recycling. Complying to RoHS reduces the amount of hazardous chemicals used in manufacturing electronics. This is why whenever you’re planning to purchase a medical isolation transformer in India, or any other electronic equipment for that matter, you should always approach a manufacturer whose products are all compliant to the RoHS certification. One such trusted manufacturer is Miracle Electronics, where every medical isolation transformer is not only RoHS compliant, but REACH compliant too!

 

Choosing The Ideal Core For Your SMPS Transformer – Miracle Electronics

 When you’re looking to transfer electrical power effectively while also providing galvanic isolation, an SMPS transformer proves to be the best choice that provides a clear barrier against dangerous high voltages from passing to the output. This is thus a safe and space-saving option, unlike other traditional linear kinds of transformers.

But when planning on having SMPS transformers manufactured for your application, you also need to be capable of making the right core choice. This choice is generally based on your power requirements, the frequency required, and the switching topology. Let’s help you know some basic considerations to make the right material, shape, and size selection.

Core material

It’s basically ferrite that is used for making the core of an SMPS transformer; the reason being that its frequency spectrum ranges between 20 kHz to 2 MHz, thanks to its reduce expense and minimal losses. But, ferrites should be employed in the saturating approach for low power and low frequency functioning. In the case of high power functionality, a tape-wrapped core used as the saturating core, with a ferrite core used as the output transformer, proves to be a better choice.

Core type

There are a variety of different core types you can choose from, some of the most popular ones stated below. Each core type has its own size and shape advantages. Let’s check them out.

EFD cores – EFD cores are economical flat design cores that offer excellent space utilization for transformers or inductors. They’re thus ideal for compact transformer and inductor applications.

EP cores – EP cores are circular center-post cubical designs that surround the coil thoroughly, with the exception of PCB terminals. This eliminates the influence of air flow crevices established at mating walls in the magnetic track, giving a more significant volume ratio to the absolute area used.

ETD and EER cores – ETD and EER cores are those with a round center-post and broad winding areas which offer the advantage of a short winding path length, and thus minimum winding resistance. They are absolutely good for high power designs and multiple output designs.

PQ cores – PQ cores have a maximum ratio of bulk to winding region and surface area. This results in comparatively fewer turns with a maximum winding area, lesser space consumed, and maximum inductance.

A perfect transformer is one that promises minimal core decline, while demanding the very least volume of room. The core loss is affected by the flux denseness and frequency. Having all of this considered is of utmost importance when selecting both the transformer and the core. This is why, when making your core choice, it is always advisable to work with an expert SPMS transformer manufacturer in India, one like MiracleElectronics. That’s because the expert engineers available here can help choose the most suitable material and dimensions for your particular project, so that your expenses are minimized, and profits maximized. Moreover, Miracle Electronics’ SMPS transformers are all RoHS and REACH compliant, thus assuring quality performance and minimal power wastage.

 

Choosing Segmented Cap Transformers Over Conventional Ones - Miracle Electronics

When you’re operating a critical application, something involved with medical, aerospace, or military, you’re always trying to settle down on a few crucial decisions. One such decision may be determining the kind of transformers you want to use, upon which lots of electrical and signal-based outcomes will depend. 

For instance, if you are into the medical industry, deciding upon the kind of medical isolation transformer in India you want to use for your applications, you may be unable to decide whether you should opt for a simple conventional one, or go in for a more radical one installed with segmented cap technology. If this is what you are unable to decide upon, you’re at the right place! We’ll help you know how a basic transformer is different from a segmented capped one, and how the latter can prove to be beneficial.

The basic construction of a toroidal transformer

A toroidal transformer has a basic method of construction which involves the following steps.

Creating a steel core – insulating the core – winding a magnetic wire around the core to create a primary winding – insulating the primary – winding a magnetic wire over the insulation to create a secondary winding – and finallyinsulating the secondary to complete the transformer.

Mounting the transformer

Once the transformer is manufactured, it is mounted either using a mounting washer and bolt, or by filling the center of the transformer with an epoxy, with a hole for a bolt.

The role of segmented core caps

Toroidal transformers are generally plain, but there are certain applications where additional segmented core caps are used. These core caps are mainly used to support the primary and secondary windings in alternate sectors to reduce leakage current. The insulating segments insulate the windings from the core over the full range of windings, allowing for double-wall insulation between adjacent windings, thus reducing leakage current to a great extent, as compared to conventional toroidal transformers. They also help to directly cool the core through ambient or forced air, without interfering with the insulation.

The construction of core caps

Several modular electrically insulating segments are snapped or joined together to form an annular or semi-annular core cap design to fully or partially cover the transformer core. The number of such segments that are required to complete a core cap is predetermined, based on the angle at which the adjacent walls are placed to each other. This is because the walls, which include male and female connector portions, are all disposed at a predetermined angle relative to each other, typically 30, 45, or 60 degrees. Typically, there are identical core cap segments in a single core, but there may also be groups of different segments spanning different arcs. The latter is basically seen in customized core cap designs that require certain particular properties and characteristics.

The benefits of a core cap design

Reduced costs – When a core cap design involves snapped segments, the cost to assemble the caps is reduced because the process of snapping requires lesser skill level than other techniques. Also, the cost to tool a smaller part for injection-moulding is lesser than the cost of tooling a larger part.

Reduced time – When a core cap design meets safety specifications for creepage and clearance, the manufacturing time is reduced because of no requirement for ground and inter-winding insulation and outer wrap. Moreover, the windings can be wound on one single machine, thus reducing the handling time.

Reduced temperature rise – When a core cap design allows airflow around the core and windings, while keeping creepage and clearance specifications safe, the temperature rise is reduced because there will be a direct path for the heat to escape from the un-insulated core into the environment, without having the windings and insulation to trap the heat within.

Reduced weight – When a core cap design includes mounting holes, the weight of the transformer is significantly reduced because there will be no center epoxy or mounting washer required.

As you can see, segmented cap transformers can offer significant reduction in leakage current, heat rise, costs, and time invested, in comparison to standard toroidal transformers. All of this combined, segmented cap transformers are lighter, faster, less expensive, and are rated for extended power for the same volume. This makes segmented cap transformers the ideal choice for critical applications like medical isolation transformers. So, whenever you are looking for an advantageous medical isolation transformer in India, you know what you have to choose. But, if you want a transformer that complies with applicable requirements, you need a manufacturer who you’re sure will provide you with only genuine standard transformers. One such reliable manufacturer  is Miracle Electronics, where every transformer is RoHS and REACH compliant, and also adhered to the regulations under UL 60601-1 standards.