What’s best: “TR CU” or “EAC” Certification?

Sometimes we get questions regarding TRCU & EAC and which is best. I thought it would be good to try to help our customers with this short post on what they are and how they are interpreted.

The compliance with current standards of the technical regulation is critical for importing products subject to conformity to Russia and other Eurasian Economic Union member states.

Many manufactures are confused by the conformity assessment process with what's the difference between TR CU Certificate and EAC Certificate?

It is two different names for the same process of conformity assessment, whereby both terms are wrong or incomplete and misleading translation.

The background of the names is historical when the standardisation originated in the former Soviet Union. The new system of standardisation covers a large part of Eurasia.

This system was known as GOST an abbreviation of "Государственный Стандарт", which translates into "state-standard". and was umbrella standardisation in the Soviet economy. 

With the disintegration of the Soviet Union in the 1990s, several of the member states started developing their standard and conformity assessment procedures, to simplify the confusing GOST system.

Around 2002/2003, the "On technical regulation" law passed in the Russian Federation declaring that new technical guidelines are developed. Subsequently, the "Technical Regulation" "TR" formed containing fixed requirements for products, services & manufacturing processes.

Russia, Belarus & Kazakhstan founded their Free-Trade-Association which eventually became known as a "Customs Union" "CU". Allowing a single technical regulation to facilitate the sale of goods & services between the member countries underpinned by a common standard "TR CU"

Later when Kyrgystan & Armenia joined an opportunity to enhance standardisation further, Europes "CE" mark would be an appropriate model in which to combine with, developing into what today is the "EurAsian Confirmaity" or EAC certificate.

Now EAC is the proper standardised name but is commonly interchanged when TR CU, GOST standard is mentioned/required.

Transformers supplied from ITL destined for the EurAsian market will have the correct EAC certification attached. If you need a copy of our certificate for your project, feel free to reach out to us at marketing@itl-uk.com where one of our team will assist.

Getting the best value out of your CT purchase (Pt.1)

Bit of a wordy headline but as part of my getting the best value out of your purchase series, in this weeks post I am focussing on Metering or Measurement Current Transformers.

When a customer asks for a quotation, he/she may have a price in mind. That might be based on previous purchases or a hunch, but none the less a price is ingrained.

Current Transformers (CT's) while a relatively simple product in nature, sometimes customers are not always sure about what they need and give you a specification that is wildly over-specified for the application. As a CT manufacturer, we understand you are not experts. However, loaded with some knowledge on the factors that can influence price, then there is an opportunity to extract the higher value from your purchase.

RATIO: Primary (input) & Secondary (output) Current Ratio (e.g. 200/5A)

VA: Total instrument burden, including the length of any pilot wires along with square mm of the cable (e.g. 4sqmm).

CLASS: Accuracy required for operation (Tariff, Measurement or Indication

DIMENSIONS: Maximum & Minimum ( the space you have available to fit the current transformer, e.g. for a ring-type Inside Diameter ID, Outside Diameter OD, Axial Length AL).

  1. By specifying a higher VA or ACCURACY CLASS than necessary will likely result in a more expensive product.
  2. Cost generally increases as the Current Transformers inside diameter (ID) increases.
  3. 1A Current Transformers are typically more costly than 5A, why I hear you say - 200/1A has 200 turns of copper whereas 200/5A has 40 turns of copper thus an 80% cost saving on copper, not to mention a reduction in the overall dimensions).
  4. Potentially unnecessary accessories such as mountings which are chargeable extras. (Most customers have their own preferred and cheaper method of mounting inside the switchgear).

Considering the above plays a big part in getting the right product for the right price.

For this post, we will consider IEC 61869 as the default standard, as this is our usual customer requirement. However, should you need IEEE/ANSI or AS (Australia) we are just as at home with these specifications?

IEC 61869 standard:

There is also Class 3 & Class 5 but rarely used, most people opting for a Class 1 as a better alternative.

High accuracy classes like 0.2s & 0.5s often require a special type of core material which in itself very expensive, so this accuracy class should only be selected when a tariff application is required.

We appreciate our customers are not specialist in transformer design but have found that one of the most common misunderstood factors about specifying a current transformer (CT) is the Burden or VA. For example, if you double the burden from 5 to 10VA, you will increase the electrical steel content and thus have a significant impact on the unit price so you must get this right.

The burden is the load imposed on the secondary of the CT at rated current and is measured in VA (product of volts and amps). The accuracy class applies only to loads at rated VA and below, down to one-quarter VA. The burden on the secondary of a CT includes the effect of pilot leads, connections etc. as well as the instrument burden itself.

In situations where the meter is remote from the current transformer, the resistance of the pilot wires may exceed the meter impedance many times in these cases it is often economical to use 1 amp meters and CTs.

The diagram shows the burden imposed on the CT due to a run of pilot wire, so a pilot loop of 2.5mm2 wire, 60 metres long (30 metres distance) has a load of 12.5 VA on a 5 amp CT but only 0.5VA on a 1 amp CT.

Typical Meter Burdens (depending on the pilot lead length):

Moving iron meter 1-2VA

Moving coil meter 1-2.5VA

Digital instrument 1-5VA

Maximum demand indicator 3-6VA

 

Want to find out more about the Principles of Measurement Accuracy? Download our FREE application note.

Got a project where you need help with your CT or VT requirement? Reach out to our engineering team and share your requirements. We're here to help.

The Importance of Transformer Insulation Materials

Typically trаnѕfоrmеrѕ аrе сlаѕѕifiеd intо diffеrеnt tуреѕ such аѕ power transformer, рulѕе trаnѕfоrmеr, instrument trаnѕfоrmеr, audio transformer, RF transformer. It iѕ сlаѕѕifiеd into different ways bу itѕ роwеr capacity, frеԛuеnсу rаngе, vоltаgе сlаѕѕ, сооling type, аррliсаtiоn, рurроѕе, accuracy class, burden аnd bу itѕ winding turnѕ. It iѕ соnѕtruсtеd uѕing аir соrеѕ, tоrоidаl соrеѕ, ѕоlid cores and lаminаtеd steel cores. Aссоrding tо itѕ mеthоd оf mounting it iѕ сlаѕѕifiеd intо pole and рlаtfоrm, ѕubwау, switchgear and it iѕ сlаѕѕifiеd intо single and роlу-рhаѕе bу itѕ numbеr оf рhаѕеѕ. Depending on its рurроѕе it can be classified into Current аnd Cоnѕtаnt current, variable аnd соnѕtаnt vоltаgе.

Insulation iѕ оnе оf thе mоѕt important qualities thаt a trаnѕfоrmеr hаѕ, often under-appreciated. In fасt, the durability and ѕtаbilitу of a trаnѕfоrmеr highlу depend upon the рrореr application and utilisation оf the insulation mаtеriаlѕ рrеѕеnt within it. This mеаnѕ thаt other than mеtаlliс components likе ѕiliсоn ѕtееl аnd сорреr, don't suffer a mechanical or electrical breakdown thus aiding decades of service life.

A Power Transformer inѕulаtiоn ѕуѕtеm соnѕiѕts either liquid or gas combined with ѕоlid materials. Petroleum-based оilѕ have been uѕеd tо insulate роwеr trаnѕfоrmеrѕ ѕinсе 1886 and thе mid-1970ѕ whеn the flammability оf minеrаl oil wаѕ a соnсеrn since then been соmрlеtеlу phased оut of trаnѕfоrmеr рrоduсtiоn due to еnvirоnmеntаl concerns. It hаѕ bееn rерlасеd bу аnу оf a widе vаriеtу оf high-flash-point fluidѕ (ѕiliсоnеѕ, high-flash-point hуdrосаrbоnѕ, chlorinated bеnzеnеѕ, оr chlorofluorocarbons).

Gаѕ ѕуѕtеmѕ include nitrоgеn, аir, аnd fluоrоgаѕеѕ. Thе fluоrоgаѕеѕ are uѕеd tо аvоid combustibility аnd limit secondary effects of internal fаilurе. Sоmе trаnѕfоrmеrѕ have bееn соnѕtruсtеd using lоw bоiling-роint liԛuidѕ such as Frеоn whiсh аllоwѕ imрrоvеd heat trаnѕfеr uѕing a 2-рhаѕе cooling system.

Within thе соrе аnd соil аѕѕеmblу, inѕulаtiоn can be dividеd intо twо fundаmеntаl groups: mаjоr inѕulаtiоn and minоr insulation. Mаjоr insulation ѕераrаtеѕ thе high аnd lоw-vоltаgе windingѕ, аnd the windingѕ tо core. Minоr inѕulаtiоn mау bе uѕеd bеtwееn thе раrtѕ of individuаl соilѕ оr windingѕ dереnding on construction. Finаllу, inѕulаtiоn is applied to each ѕtrаnd of соnduсtоr and or grоuрѕ оf ѕtrаndѕ forming a single turn.

Understanding the transformer application is key to understanding what insulation materials to use. In Power Transformers insulating рареr аnd cardboard are the twо main insulating mаtеriаlѕ used for isolating рrimаrу and ѕесоndаrу windingѕ with thе mаin соrе. Whereas in some low and medium voltage applications Epoxy or Polyester Resin systems protect while in others a plastic case, polyester tape or crepe paper are most suited.

In the end, insulation plays a vital role in the operation of a transformer; getting it wrong can be expensive.

Need an Instrument Current Transformer or Voltage Transformer up to 36kV?

Drop our technical team an email to discuss your requirement or jump over to our contact form and complete, we would love to hear from you.

UL Recognised Components

Instrument Transformers Limited (ITL) is happy to announce our new range of UL recognised component, low voltage current transformers, and is yet another milestone of achievement in our expanding portfolio.

Tape Finish, Resin Cast & Plastic Case models with prefix part numbers 560, 561 & 562 will fall under our UL programme (File Number E502882) and highlights our ongoing commitment to providing the very best customer solutions. So if a UL requirement is what you need, just let us know we would be happy to help.

To understand the importance of UL and what it stands for we need to look at its' history: -

Underwriter Laboratories, or UL, is a global company with headquarter in USA, Illinois. Offering a variety of services to help business improve their products or services and demonstrates they are safe to use and comply with set quality standards and regulations. From a manufacturer point of view, the UL affixed label gives our customers additional confidence in the safety, quality, and reliability of our product.

In 1893 a fire at the World Columbian Exposition in Chicago Illinois, where sixteen people lost their lives. Prompted William Henry Merrill, Jr who would go on to become UL's founder. Proposed the idea of an independent electrical testing laboratory and in 1894 the Underwriter Electrical Bureau was born. Finally, after several name changes, in 1901 the name Underwriter Laboratories as we know it today got incorporated, and the business took off.

UL published the first standard in 1903 for a Tin Clad Fire Door and has since branched out in a variety of industries (e.g., building construction, aircraft, security, home appliances, resins, TV's and much more). In 1956 UL also expanded internationally and started to certify products made in Europe.

ITL continues its expansion into North America & the Petro-Chemical processing space, where electrical switchgear equipment manufacturers need UL approved components. 

Which is part of our ongoing drive to support our global customer base with the right products for the right application at the right price.

Got Questions?

Drop our technical team an email to discuss or jump over to our contact form and complete, we would love to hear from you.

SAP Ariba – Good or Bad?

SAP Ariba is the leader in spend management. It began with a mission to help companies control spending and cut costs by making it easier for buyers and suppliers to work together. In 2012, Ariba was acquired by SAP, the world’s largest business software company, and in 2016 launched its new new brand identity.

While SAP Ariba is open to all systems and all types of goods and services, its unified name conveys to customers the value of combining solutions for procurement and supply chain collaboration with SAP’s expertise in enterprise application software and supply chain management.

SAP Ariba is how companies connect to get business done. On the Ariba Network, trading partners from more than 3.6 million businesses, operating in more than 190 countries, discover new opportunities, collaborate on transactions, and deepen their relationships.

  • Large, midsize, and growing companies use an end-to-end, automated system that simplifies the management of everything from sourcing to payments, all in one place.
  • With intelligent spend management tools and network-generated insights, customers establish sustainable, trusted connections with partners while ensuring efficient, error-free transactions.
  • Buyers can manage the entire purchasing process as they control spending, find new sources of savings on both direct and indirect goods, and build healthy, ethical supply chains
  • Suppliers can connect with profitable customers and efficiently scale existing relationships, simplifying sales cycles and improving cash control along the way.

The Ariba Network makes it easy for buyers and suppliers to collaborate on transactions, strengthen their relationships, and discover new business opportunities. Buyers can manage the entire procurement process from source to settle, while controlling spending, finding new sources of savings, and building a healthy, ethical supply chain. Suppliers can help buyers achieve their procurement transformation goals, while boosting customer satisfaction, simplifying the sales cycle, and improving cash flow.

Content Source: Ariba.com

In the end it is the choice of the supplier to either join or not. Some of your customers may insist while others are not on the platform, that is all fine at least you are able to make an informed judgement. It might be sales related or foresight to where you want to see your business in the future to join. Our experience over the past years has been good and are able to engage and participate in number of projects easily.

Find Instrument Transformers Limited on SAP Ariba

Need an Instrument Current Transformer or Voltage Transformer?

Drop our technical team an email to discuss your requirement or jump over to our contact form and complete, we would love to hear from you.