All types of electrical equipment (transformers, electrical machines and electrical switching devices) require different means for full-rate diagnostic. However, in case of direct-current resistance measurement the multipurpose instrument MIKO-2.3 can be used. Resistance range for the above listed equipment is wide and resides within the values from 10-3 to 600А and more. For monitoring of a transformer or a sole circuit-breaker, for instance, a micro-ohmmeter, milli-ohmmeter, thermometer and even kilo-ohmeter are needed. It means that you have to use three or even four instruments one at a time which is not usually convenient. Increasing of the number of instruments increases not only the total cost of a set, but also its weight which complicates transportation of equipment to remote facilities.
Milli-ohmmeter mode is designed for measurement of direct-current resistance in circuits with high inductance (transformers, electromagnets etc.) within the range of 100 μΩ – 1 kΩ. Two submodes are used here: measurement of one-phase and three-phase windings. Besides, MIKO-2.3 has a function of automatic recalculation of resistance measurement results for a three-phase winding:
- Calculation of relative deviations of resistance values of moving coils between each other;
- recalculation of resistance values of moving coils connected according to the triangle scheme into resistance values of phase windings;
- recalculation of resistance values of moving coils connected according to the star scheme into resistance values of phase windings;
- recalculation of a winding resistance measured at current temperature T into resistance at base temperature Ɵ with due account for the winding material.
Test cables of unique and ergonomic design
MIKO-2.3 input cables are equipped with crocodile clips with G-cramps of unique design that has no analogues by other manufacturers of instruments. This design ensures quick and faultless connection to an object that excludes errors of measurement of small resistance values, and ensures reliable contact even in case of oxygenated surfaces of an object. Besides, there is an option of a four-clamp connection of the instrument cables to circuit-breaker bushings and to transformers through external potential contacts.
0.1 μΩ – 0.1 Ω
Alpha-graphic, 6 x 2.5 cm