Safely Performing a Megger Test for Medium and Low Voltage Encapsulated Dry Resin Transformers

The safety of any transformer or other electrical device should always come first. Low Voltage and Medium Voltage Encapsulated Dry Resin Transformers testing is required for safe operation. We can find any potential problems or weaknesses in the insulation of dry resin-filled transformers by performing routine testing. These tests allow us to take preventive action for your secure working environment.

Encapsulated Dry Transformer Components for Safety and the Environment

Electrical transformers that don't need a liquid coolant like oil are known as dry transformers. You may know them as resin-filled transformers, cast resin transformers or solid insulated transformers.

They use air for insulation and cooling. Dry transformers are popular because of their safety, effectiveness, and environmental friendliness in commercial and industrial environments. They are used in manufacturing facilities, renewable energy production, power distribution systems, and other areas.

Dry transformers are made up of a number of essential parts. The primary components consist of a laminated steel core that minimizes energy losses and a copper or aluminum conductor coil. Paper, fiberglass, or epoxy resin are used to insulate these windings, ensuring both electrical insulation and protection from impurities and moisture. For safety and cooling, the transformer is housed in a solid, vented casing.

Let's take a look at Megger test equipment for dry transformers and looking at the test results.

Megger Test Equipment Finds Insulation Weakness, Moisture, Safety Hazards

What is a megger test? Megger test equipment is effective for identifying moisture, insufficient insulation, and other possible problems in transformers. The test procedure includes applying DC voltage to the transformer windings during the test. The Megger test assists in locating any deterioration or breakdown in the insulation material by evaluating insulation resistance.

When looking at your megger test report, keep in mind the resistance reading will be lower than expected if the insulation is damaged, suggesting potential defects or moisture infiltration. With the help of this test, insulation issues like cracks, contaminants, or age can be found that could otherwise result in electrical problems, short circuits, or even catastrophic failures. Early detection of these problems allow necessary repairs or maintenance to be carried out, ensuring peak performance and averting safety risks. If you’re looking to invest in megger test set, check out the Megger Trax 220 Test Set for insulation resistance, winding resistance, turns ratio, dissipation factor, and more.

Transformer Megger Test Step-by-Step Procedures

Safety First:  Make sure the transformer is totally de-energized and you’re wearing appropriate personal protective equipment (PPE).

Setting up the Megger:  Prepare your Megger test device according to manufacturer directions. Verify that it’s calibrated and in good working order.

Disconnect Power:  To prevent incidents from occurring, make sure the transformer's power supply is completely cut off.

Clean your Transformers:  Clean the transformer's terminals and insulating surfaces. Any debris, moisture, or dirt that could compromise the test's accuracy should be removed.

Connect the Leads:  It’s recommended to connect the lead with the higher voltage (often red) to the high-voltage side and the lead with the lower voltage (typically black) to the low-voltage side.

Set Megger Test Duration:  The typical time frame is one minute, but it's always a good idea to check the manufacturer's instructions for any particular specifications.

Launch the Test:  Turn on the testing device. The transformer windings will receive a high-voltage DC voltage, and the instrument will measure the insulating resistance.

Interpret Megger Test Results: Compare insulation resistance with the reference value or the range the OEM specifies.

Based on test results, no urgent intervention may be needed if the insulating resistance is within the manufacturer’s stated range. Do repairs or arrange for maintenance if the reading falls below the designated threshold.

Looking for a Medium Voltage Dry-Type Transformer Testing Service?

This test helps you identify risks and prevent electrical faults or failures by identifying insulation weaknesses, moisture and other potential problems. The Megger test offers useful information about the insulation integrity of the transformer when you’re doing maintenance and repairs to maintain performance and avoid safety risks. Regular Megger testing extends the life and dependability of transformers in a safe environment. Make megger testing a routine and seek professional services if you’re not qualified to use the testing equipment.

Looking for a Medium or Low Voltage transformer or having one tested? A Megger Testing Service for transformers using test equipment like the Megger Trax 220 Test Set is crucial for verifying the effectiveness and safety of transformers.

Contact EMSCO customer service to arrange testing. Ask about EMSCO testing services for dry-type medium voltage transformers. Our new Megger Trax 220 Test Set allows us to perform a wide range of tests, including insulation resistance, winding resistance, turns ratio, dissipation factor, and many others.

Industrial Power Protection: Unveiling Molded Case Circuit Breakers (MCCBs)

In the realm of industrial power distribution, ensuring safety, reliability, and efficiency is of utmost importance. To protect electrical circuits and equipment from overcurrents and short circuits, engineers often turn to molded case circuit breakers (MCCBs). These robust and versatile devices play a crucial role in safeguarding industrial power systems, ensuring smooth operations and preventing potential hazards. In this blog post, we will delve into the features, benefits, and applications of molded case circuit breakers in industrial settings.

The Anatomy of Molded Case Circuit Breakers:
Molded case circuit breakers are named after their housing, which is typically made from molded insulating materials such as plastic or fiberglass. Inside the casing, these breakers comprise essential components like the trip unit, operating mechanism, and current-carrying contacts. The trip unit is responsible for detecting overcurrent conditions and tripping the breaker when necessary, while the operating mechanism ensures the mechanical action of opening and closing the circuit.

Wide Range of Current Ratings:
MCCBs are available in a wide range of current ratings, making them suitable for diverse industrial applications. They can handle currents ranging from a few amps to thousands of amps, allowing engineers to choose the appropriate breaker based on the specific requirements of their power distribution system.

Accurate and Reliable Protection:
One of the primary functions of an MCCB is to provide precise and reliable protection against overcurrent conditions. The trip units in MCCBs are designed to respond swiftly to abnormal current levels, effectively isolating the faulty circuit and preventing potential damage to equipment. With adjustable tripping settings, engineers can customize the MCCBs to suit the unique characteristics of their industrial power systems.

Thermal and Magnetic Protection:
MCCBs offer both thermal and magnetic protection, catering to different types of faults. The thermal trip element responds to overloads caused by long-duration, low-level overcurrents, while the magnetic trip element reacts to short-circuit currents. This dual protection mechanism ensures comprehensive safety coverage in industrial power settings.

Selectivity and Coordination: 
Industrial power distribution systems often have multiple levels of circuit breakers, from the main distribution board down to individual branch circuits. MCCBs provide the advantage of selectivity and coordination, which means that when a fault occurs, only the nearest MCCB to the fault will trip, leaving other downstream breakers unaffected. This feature minimizes downtime and optimizes system performance during fault scenarios.

Ease of Maintenance and Retrofitting:
MCCBs are designed for easy maintenance and replacement. With proper periodic inspection and testing, their lifespan can be extended, contributing to cost savings. Additionally, they are compatible with various accessories and digital communication modules, enabling seamless integration into modern industrial automation systems.

Versatility and Applications:
Molded case circuit breakers find applications across various industrial sectors, including manufacturing plants, data centers, commercial buildings, oil and gas facilities, and mining operations. They provide vital protection for motors, transformers, generators, distribution boards, and other critical electrical components.

In conclusion, molded case circuit breakers are indispensable assets in industrial power settings. Their accurate protection, ease of maintenance, and compatibility with modern automation technologies make them a reliable choice for ensuring the safety and efficiency of power distribution systems. By understanding the benefits and applications of MCCBs, engineers can make informed decisions to secure their industrial power infrastructure effectively.

Find the Molded Case Breaker you need here!

Medium Voltage Dry-Type Transformer Testing

EMSCO is pleased to announce that we are now offering testing services for dry-type medium voltage transformers. Our new Megger Trax 220 Test Set allows us to perform a wide range of tests, including insulation resistance, winding resistance, turns ratio, dissipation factor, and many others.

If you require any specific test for your transformer, simply let us know, and we will be happy to accommodate your needs. We want to make sure that you receive exactly what you need, so don't hesitate to let us know your specific requirements.

Furthermore, all of our Medium Voltage Dry-Type Transformers come with a 1-year warranty, giving you the peace of mind that you're making a reliable investment.

We encourage you to take a look at our current inventory of medium voltage transformers and contact our team to discuss your needs. Our testing services, combined with our vast selection and commitment to quality, make EMSCO the ideal choice for all your transformer needs.

Shop Medium Voltage Transformers

Molded Case Circuit Breaker Testing

At EMSCO, we offer a full range of services for testing and purchasing molded case circuit breakers. Our experienced team utilizes two state-of-the-art circuit breaker test sets—the Megger DDA-6000 Universal Circuit Breaker Test Set and the Phenix Model HC40C High Current Test Set—to thoroughly assess your circuit breakers. Whether you want to buy a breaker from us or simply require testing, we provide detailed test reports for all units.

We take pride in our efficiency and fast turnaround times. Most breakers can be tested and shipped on the same day, and we maintain a diverse inventory of breakers ranging from 15 to 5000 amps.

For circuit breaker testing or if you're in the market for a new one, EMSCO is your go-to destination. Reach out today to speak with one of our knowledgeable sales representatives about your testing needs.

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High Amperage Square D Bus Plugs

EMSCO got in a load of high amperage Square D Bus plugs. These bus plugs are a mixture of fusible and breaker plugs available in a wide variety of amperages, such as models PTQ46160GH and PTPA361000N. In addition to these bus plugs, we have a huge stock of Square D busway all the way up to 4000 amp.

Whether you need a single bus plug or a new busway run, EMSCO is here for all your bus plug and busway needs. Contact as salesman today with any questions.

Square D Model-6 Motor Control Centers

EMSCO has recently received a new shipment of Square D Model-6 Motor Control Centers. These Control Centers come with a variety of starter and breaker feeder buckets, and we are excited to announce that there are more than 20 Twin breaker feeder buckets available, each with a capacity of 100 amps. If you're interested in purchasing any of these high-quality motor control centers or have any questions, please don't hesitate to contact us today.

Square D Model-6 MCC Structure

EMSCO recently got in more Square D Model-6 MCC structure.

The structure has multiple Size-5 FVNR Starter Plug-On buckets as well as Size-4.

All with solid-state overloads and circuit breaker disconnects.

Whether you need a complete motor control center, an add-on section, or a single bucket we have you covered.

Contact a salesman today.

Square D Power-Zone NW 5000 Amp Main Tie Main Lineup

EMSCO recently got in a Square D Power-Zone NW 5000 amp main tie main lineup. The lineup includes (3) NW50H3 with Micrologic 6.0P trips, (2) NW32H3 with 5.0A Micrologic Trip, (1) NW32H3 with 6.0A Micrologic Trip. (1) NW20H3 with 6.0A Trip, (1) NW16H3 with 6.0A Micrologic Trip. We can customize this panel to meet your needs.

With this lineup, we also received (2) Square D Power Cast Transformer and Square D 15KV Medium Voltage Fusible Switches:

2500/3750VA 12470-480Y/277V Square D Power Cast II K-4
Two (2) 2500/3333KVA 12470-480Y/277V Square D Power Cast II K-4
Whether you need a single breaker or a complete substation lineup we have you covered. Give us a call today!

General Electric Spectra 480/277 Volt Main Breaker Panels with Spectra Breaker Distribution

EMSCO recently got in seven (7) GE Spectra 4000 amp 480/277 volt main breaker panels with Spectra breaker distribution. The main breakers are GE Power Break II SSD40G440 with Entelliguard Trip TU Trip Unit. All have multiple SKLL frame 1200 amp branch feeders breakers. Each feeder breaker fed a GE Spectra 1200 amp 480/277 Volt MLO panel that are also now part of EMSCO’s stock.

Call us today so we can customize these panels to fit your needs.

Westinghouse Medium Voltage Vacuum Contactors

Newly arrived, EMSCO has received a shipment of Westinghouse medium voltage vacuum contactors. These are open style contactors, 720 amp, and vacuum type OEM Model-A AC contactors; 720-amp, 3-phase, 7200 volts. Part number EMAN3NN8X1-M3.

If you are interested in these medium voltage vacuum contactors or any others, please give us a call today (1-800-328-1842) to speak with our sales department. We’ll be happy to provide quotes, additional information, or find any industrial electrical product or part that you may need.