Reviews

The PKV/U3.1 (PKV/U3.0) instrument for non-destructive testing of HV circuit-breakers has been used by our personnel since July 2008. During this period all the types of circuit breakers installed at the substations of Federal Network Company that are serviced by Vologda Company of Main Electric Networks have been tested, namely: VVB-220, HPL-220, U-110, and MKP-110.

When purchasing this instrument we took into account positive experience of using previous versions of instruments for non-destructive testing of HV circuit-breakers (PKV-5, PKV-6, PKV-5M).

The use of PKV/U3.1 Instrument reduces time for HV circuit-breaker maintenances and raises the quality of works performed. The instrument allows check of practically every rated parameter of a circuit breaker (time proper of closing/reclosing at each pole; full time of traverse pass; time delay of contacts closing/reclosing; contacts bounce, traverse rebound and overshoot, voltage change at electric magnets, and many others).

The main advantages of the instrument are: small size, high accuracy of measurements, higher versatility as against its foreign analogues, a simple method for detecting the incipient defects, drawing up the defects lists without circuit breaker dismounting, possibility to connect the instrument to a computer, and immediate visualization of the HV equipment state.

We willingly recommend PKV/U3.1 and other SKB EP instruments for non-destructive control of HV circuit-breakers to all the companies dealing with servicing, maintenance, mounting and commissioning of high-voltage equipment.

MIKO-1 microohmmeter has been used by our Company for commissioning operations since 2006. Your instrument is rather convenient in use as it is powered from an in-built battery; it has small size and weight; there is a convenient bag for its transportation and operation. These merits of the instrument allow us to use MIKO-1 in tough conditions of switchgears and for measurement on disconnection switches, circuit breakers and switchgear busbars. Control of the process is rather simple and informative, accuracy of measurements is high, capacity of the battery is sufficient for a large number of measurements.

Previously our Company used other instruments during commissioning. As against its analogues, MIKO-1 is a leader of Russian instrumentation; it has comparatively low price, it is reliable, convenient in operation, transportable and is completed with appropriate measurement cables. I should like to note that customers can order cables of different length from the Catalogue. I can recommend the MIKO-1 instrument to all the companies dealing with adjustment, maintenance and operation of electric equipment in the networks, at power plants (thermal, hydro, etc.), and by electrical laboratories of industrial enterprises.

branch of OJSC MRSK of North-West uses instruments manufactured by SKB EP, namely PKV/U2, PKV/U3.1, and MIKO-1. Types of circuit-breakers controlled by the Instruments include: VMT-110, VMT-150, MKP-110, VVSh-150, VT-35, and VM-35.

Specialists of our Company operating those instruments note their benefits:

• Instruments are robust and simple in operation;
• Software for the instruments is user-friendly;
• The data obtained can be interpreted and compared in detail by overlapping the graphs obtained on the available ones.

The PKV/U3 Instrument has been used by our personnel since March 2008. Use of this instrument raised the quality of maintenances assessment since design of the instrument allows check of practically every rated parameter of a circuit breaker (time proper of switching on/off; pass in contacts; time delay for contacts closing/reclosing; forcing in; contacts bounce, etc.).

It should be specially noted that the instrument kit includes a notebook that allows assessment of the maintenance quality immediately after the measurements with the help of curves and diagrams on the screen, and reveals concealed defects of certain parts of a circuit breaker. Ability of the instrument to measure "Open" and "Close" current consumed by electromagnet windings reveals concealed defects in the electromagnet windings.

One of the advantages of the PKV/U3 instrument is that the number of channels for reading the time and speed characteristics of the VV-500B circuit breaker allows their recoding throughout the pole instantaneously.

Software of the notebook is user-friendly and at the same time multifunctional. It incorporates all the functions required for reading the time and speed characteristics, particularly: manipulation of PKV/U3 instrument, review of the measurement results in the tabular and graphic (colored) form, storage of the data obtained on a hard disk, creation of a data base of measurements performed, printing out the reports.

In view of the fact that much attention has lately been paid to assessment of the equipment state for making a decision on its shutdown for maintenance, the use of PKV/U3 instrument for non-destructive testing of internal parts of a circuit breaker reduces the scope of maintenance works and facilitates identification of circuit breakers that need urgent repair.

The MIKO-1 Instrument has been used by the Company for equipment adjustment since November 2008. With the help of MIKO-1 we measured transient resistance of BNA-10, BNA-SEShch-10 circuit breakers, of vacuum circuit breakers Tavrida Electric, of high-voltage breakers 6, 10, and 110 kV, of welded and joined connections of 0.4, and 6/10kV busbars.

The instrument is rather convenient and simple in operation, it does not require power supply from the network, which is rather convenient when measurements are made at newly built facilities.

Battery capacity is rather high as it allows up to 40-50 measurements without recharging at a temperature of down to -20ºС. Connecting wires remain elastic even at low temperatures.