Опис
The microohmmeter is designed to measure the electrical resistance to direct current of components of electrical circuits that are not under voltage.
A microohmmeter can be used to measure:
- transient electrical resistance of high-voltage switches and disconnectors;
- electrical resistance of soldered, welded and screw connections;
- the electrical resistance of the connection contacts and the resistance of the ground part of the circles of grounding devices;
- resistance of tires, conductors and cables.
The microohmmeter is used in all branches of industry and the national economy, regardless of the form of ownership.
The microohmmeter is manufactured in accordance with the requirements of the Technical Regulation of legally regulated measuring equipment (hereinafter referred to as the Technical Regulation), approved by the Resolution of the Cabinet of Ministers of Ukraine dated 13.01.2016 No. 94, DSTU OIML D 11:2012 Metrology. Electronic measuring devices. General technical requirements.and DSTU EN 61010-1.
Technical characteristics
Microohmmeter measurement ranges:
– from 10 μΩ to 3 mΩ;
– from 1 mΩ to 300 mΩ;
– from 0.1 Ω to 50 Ω.
The time to establish the working mode is no more than 5 s.
The operating mode of the microohmmeter is automatic or manual.
Microohmmeter accuracy class 2.5 according to DSTU OIML R 34:2014 Accuracy classes of measuring equipment.The limits of the permissible relative basic measurement error are ± 2.5% of the measured resistance.
Indication of the results of microohmmeter measurements is four-digit with a floating point on a liquid crystal indicator with backlight.
The power supply of the microohmmeter is eight AA-size Ni-MH batteries with a capacity of at least 2 A∙h and a nominal voltage of 1.2 V.
The current consumption of the microohmmeter from batteries in manual mode is no more than 0.25 A.
The current in the circuit of the measured resistance:
– in the range from 10 μΩ to 3 mΩ – a current pulse of 5 A with a duration of 0.3 s;
– in the range from 1 mΩ to 300 mΩ – a 50 mA current pulse lasting 0.3 s or 50 mA direct current in manual measurement mode;
– in the range from 0.1 Ω to 50 Ω – 5 mA current pulse lasting 0.3 s or 5 mA direct current in manual measurement mode.
The number of measurements under normal conditions of use in automatic measurement mode with fully charged batteries up to the set discharge level is not less than 1000.
The microohmmeter performs:
– automatic selection of the measurement range when measuring in automatic mode;
– indication of the process and degree of battery charge;
– automatic disconnection from the power source when the battery voltage drops to the set level;
– automatic disconnection from the power source no more than 120 s after the end of the measurement or after releasing any of the control buttons;
– memory storage of the results of the last twenty measurements.
Degree of protection of the microohmmeter housing – IP42 according to DSTU EN 60529:2014 Degrees of protection provided by casings (Code IR).
Working conditions of application:
– ambient air temperature from minus 10 ºС to plus 55 ºС;
– relative air humidity up to 90% at a temperature of 30 ºС.
The microohmmeter is designed for operation in humid conditions without moisture condensation in an open place.
The overall dimensions are no more than 230 mm x 140 mm x 59 mm.
Mass – not more than:
– microohmmeter with batteries – 1 kg;
– a set of measuring cords – 0.5 kg.
The norm of the microohmmeter’s average working time before failure is 10,000 h.
The average service life of a microohmmeter is 10 years
