Milli-ohmmeter MIKO-7M(A) new version

MIKO-7M milliohmmeter that we received in December, 2020 corresponds to the description and the declared technical parameters. With this device we check the windings of power and measurement transformers, electric motors, generators, circuit breaker contactors, busbars and other circuits.

MIKO-7M is very convenient to be used and carried, as it has a protective case. The measurement settings menu is clear, the functionality of the device is more than convenient: there are user-friendly interface, automatic measurement mode selection, high speed and accuracy of measurements. Moreover, test cables remain flexible at subzero temperatures. MIKO-7M milliohmmeter fully meets our needs and requirements.

In August 2019, our company purchased MIKO-7 milliohmmeter for the needs of the electrotechnical laboratory. This device was purchased to replace the DC bridge R333.

During the use, the device has proven itself on the positive side.

The main advantage that was noted when working with MIKO-7 is the high measurement speed that significantly reduced the time required to check the resistance of the transformer windings.

I would also like to mention the strong robust and shockproof case of MIKO-7 that allows you to transport the device without fear of damaging it.

The only inconvenience is the lack of a built-in battery for the possibility of autonomous operation. As far as we know, this flaw is taken into account and corrected in the new modification of the device MIKO-7M(A).

[Manufacturer note]: You are absolutely right. Modified milliohmmeter MIKO-7M(A) is equipped with a built-in battery. You can learn more about its characteristics on the corresponding page of our website.

During the entire operation of the device, there were no failures in its operation.

We look forward to further cooperation and recommend SKB EP as a reliable and competent partner.

To date, the following devices are in operation in the electrotechnical laboratory of the Yaroslavl Power Supply Distance of the Northern Energy Supply Directorate: MIKO-2.3, MIKO-7, PKR-1 and PKV/M7.

These devices are used in conducting a comprehensive survey of electrical equipment of substations, such as power and converter transformers, high-voltage circuit breakers, and disconnectors. During the tests, SKB EP devices gave a good account of their reliability, stability of operation, and ease of use. When using the above-mentioned devices, total measurement time was reduced.

The use of PKR-1 OLTC analyzer made it possible to more accurately determine the defects of the power transformer and tap changing device during a comprehensive check-up. The most frequently diagnosed damages are burning and adjustment of the contactor contacts of the tap changing device. The second most common defect is the burning of circuit breaker contacts. One of these defects was confirmed by the visual inspection.

The use of MIKO-2.3 and MIKO-7 devices that are dedicated to the resistance measurement in inductive circuits gave the greatest reduce of measurement time. When using an AC bridge, one resistance measurement of the 110 kV transformer winding lasted about 1.5 minutes. When using MIKO-2.3 or MIKO-7 devices, the time spent on one measurement was reduced to 30 seconds.

PKV/M7 circuit breaker analyzer is used for a comprehensive assessment of the state of high-voltage circuit breakers. As the main direction was chosen the assessment of SF6 circuit breakers of MKP-110 type. There is a big survey conducted of SF6 circuit breakers installed instead of oil circuit breakers. The use of PKV/M7 circuit breaker analyzer has reduced the time spent on the diagnostics of circuit breakers, and increased the accuracy of the data obtained. Previously, the measurements of the moving parts movement and compression were controlled by a ruler with oil drained from the circuit breaker tank. PKV/M7 circuit breaker analyzer is, first of all, more comfortable to use and has better accuracy comparing to the previously used methods.

Having experience in the operation of SKB EP devices since 2016, we can definitely recommend the use of these devices for diagnostics of energy facilities.

On October 21, 2019, SKB Electrotechnical Instrument Making LLC, in a classroom at the Novo-Sverdlovsk Thermal Power Plant, conducted a demonstration and demonstration measurements for MIKO and PKV instruments to employees of the electrotechnical laboratories of several stations of the PJSC T Plus Sverdlovsk branch of "Novo-Sverdlovsk CHP.

The measurements were performed on the VGM-20 circuit breaker in conjunction with representatives of SKB EP: Konstantin Muravin, Gennady Kurov, Natalia Korneeva. The following devices were demonstrated: the MIKO-21 microohmmeter (transition resistance of the contacts was measured) and the control device for the high-voltage circuit breakers PKV / M7 (the characteristics of the stroke, speed, time, and also the timing of the contacts were taken).

On 6 kV 5DV-A motors, designed to measure the active resistance of DC windings, the operation of millimeters MIKO-7M (A) and MIKO-9A have been shown.

Instruments have proven themselves on the good side in terms of operation and accuracy, as well as measurement speed. We recommend them for purchase and operation.

The instrument was purchased for checking the validity of our products in a production workshop - current and voltage measuring devices in the I-TOR high-voltage network with a rated voltage of 35, 110kV, rated current of 100-600A, namely: measuring the DC resistance of the current circuit of the device. All equipment diagnosed within a month has shown its serviceability - 12 phases of I-TOR-110kV and 6 phases of I-TOR-35kV.

Some features of the MIKO-7 device can be identified:

Since June 2017, the MIKO-7 instrument has been used to conduct cable and drives acceptance tests. Previously, another device was used for these purposes.

The MIKO-7 instrument has a modern interface and it is convenient in work. The advantage of the device is also its mobility. The use of this device allowed us to reduce the time allotted for acceptance tests of cables produced by our company.

Upon request for feedback on the use of the device manufactured by your enterprise, we inform you that the MIKO-7 milliohmmeter was used at FSUE PO October, the operating time was 1 year.

With this device, the transition resistance of the contact areas and the grounding of the product bodies was checked.

Our company has been using the MIKO-7M microohmmeter since May 2020.

A positive point device using in a production environment is protection against external mechanical influences and adverse weather conditions. In our work, it is necessary to carry out a large number of measurements of a 35 kV transformer with a power of up to 1600 kVA. For these needs, the specialists selected MIKO-7M and MIKO-8M instruments, however, given the clearly defined testing mechanism, the MIKO-8M functionality was redundant for us. An important role in choosing a device was played by price and, due to these factors, a decision was made to purchase MIKO-7M.

The instrument copes with its tasks good, we can recommend it for use by other companies.