Laboratory for Electrical Measurements and Instrumentation (LEMI)

Laboratory for Electrical Measurements and Instrumentation (LEMI)

Lab activity

The Laboratory engages inthe measurement and calibration of a part of electric quanties (voltage, current, resistance, power), electric measurement of non-electric quantities (deformation,
displacement, force, pressure, temperature, sound and noise, vibrations), in static and dynamic area and estimating the measurement uncertainty. Useof Labview program package enables the development of virtual measurement systems with system data acquisition and calibration of measurement chain and virtual instruments. The Laboratory has been developing the technologies ofprogram design and 3D objects production.

Head of the Lab: This email address is being protected from spambots. You need JavaScript enabled to view it., Prof., PhD

Services:

  • Deformation measurement using strain gauges
  • Measurement of electrical power and/or energy
  • Measurement of range in which the current voltage or power strength changes over time
  • Precise measurement of voltage, current, resistance
  • Design and implementation of measurement systems
  • Estimation of measurement uncertainty
  • Calibration of temperature sensors
  • Calibration of lvdt displacement sensor
  • Measurement of sound and noise
  • Microphone calibration
  • Vibration sensor calibration 
Analytical procedure and test method
Analitic procedureAnalitic procedure

Test method


 

 

 

 

 

 

 

 

 Small and medium sized equipment
Name inventory
Tech.characteristics Application Image

6.5 digit Precision Multimeter 8846A

DCV accuracy up to 0,0024 %.
DCV 100 mV – 1000 V, ACV 100 mV – 1000 V,
DCA 100 μA – 10 A, ACA 100 mA – 10 A,
Resistance 10 Ω – 1 GΩ, Frequency 3 Hz – 1 MHz,
Capacitance 1 nF – 0,1 F, Temperature -200 °C to  600 °C.
Using RS-232 or GPIB bus can be connected to a computer and controlled with a Labview program of Fluke program.

Measurement of electric voltage or current, load resistance, measurement of signal frequency and period, measurement of capacitance and temperature.

Multimetar

6.5 digit Precision Multimeter 8845A

DCV accuracy up to 0,0035 %,
DCV 100 mV – 1000 V, ACV 100 mV – 1000 V,
DCA 100 μA – 10 A, ACA 100 mA – 10 A.
Resistance 100 Ω – 100 MΩ, Frequency 3 Hz – 300 kHz.

Measurement of electric voltage or current, load resistance, measurement of signal frequency and period, measurement of capacitance and temperature.

Multimetar 2

4.5 digit Multimeter UT71E

DCV accuracy (0.025 %+5d).
DCV 400 mV – 1000 V, ACV 4 V – 1000 V,
DCA 400 μA – 10 A, ACA 400 μA – 10 A,
Resistance 400 Ω – 40 MΩ, Frequency 40 Hz – 400 MHz,
Capacitance 40 nF – 40 mF, Temperature -40 °C do 1000 °C.
Power of single phase load, up to 2500 W.
Using USB can be connected to a computer and controlled with a program.

Measurement of electric voltage or current, load resistance, measurement of signal frequency and period, measurement of capacitance, temperature and power.

Multimetar 3

3.5 digit Multimeter M3900, 12 pieces

DCV accuracy (0.5 %+1d).
DCV 200 mV – 1000 V, ACV 200 mV – 750 V,
DCA/ACA 20 μA – 20 A,
Resistance 200 Ω – 20 MΩ.

Measurement of electric voltage or current and load resistance.

Multimetar 4

Multimeter High Voltage Probe for a 20 kV

DC do 40 kV.
AC do 28 kV RMS.
Accuracy ± 2 % (20 kV), ± 3 % (20 kV – 40 kV).

Measurement of DC and AC high voltages.

Visokonaponska sonda

GPIB Interface for communication of computer and instruments

GPIB to USB.

Communiction of instrument with computer.

Gibt

RS 232 Interface for communication of computer and instrument, 3pieces

RS 232 to USB.

Communiction of instrument with computer.

RS 232

Miniature Reference Temperature Thermistor Probe 5665

0 °C do 100 °C.
Točnost ±0,01 °C.

Calibration of temperature probes.

Sonda

Temperature thermistor probe USP8528-ND, 8 pieces

-55 °C to 125 °C.
Accuracy ±0,2 °C (25 °C to 80 °C).

Temperature measurement of liquids.

Temperaturna sonda za uranjanje

Logger Hygrothermometer NT2-D

0 – 100 % RH, -30 °C do 70 °C.
Accuracy 1.5 %RH, 0.2 °C.

Measurement of air temperature and humidity.

Higrotermometar

Data acquisition measurement card NI PCI 6281

8 differential/16 referenced input channels with 18 bits resolution, 2 analog output channels with 16 bit resolution, 24 DIO, measurement ranges from ± 100 mV to ±10 V. Sample rate 650 kS/s one channel, multichannel 500 kS/s.

Temperature measurement, measurement of deformations, measurement of electric detonators properties.

Mjerna kartica

Four channel oscilloscope WaveRunner 6030, 350 MHz

Analog bandwidth 350 MHz @ 50 Ω, rise time 1 ns, 8 bits of resolution on 4 channels.

Measurement of fast changing signals, voltage, current of transducer signals (e.g. strain gauges, …).

Osciloskop

Oscilloscope High Voltage Probe for a 20 kV

Max. voltage 20 kV  including  peak AC,
max. 14 kV RMS AC (50 Hz/60 Hz).
Max. 40 kV peak pulse.
Bandwidth 100 MHz.

Measurement of static and dynamic high voltage signals.

Visokonaponska sonda za osciloskop

Transducer MI400

Measurement of more than 50 different power source parameters (V, A, kW, kVA, malfunction, power factor, Hz,…) with three analog outputs and communication with computer.
Accuracy class 0.5

Measurement of power supply properties.

Pretvornik

Precission current shunt CS-10, with temperature sensor

Max. current 10 A,
resistance 0,1 Ω.
Accuracy 0,01 %.
DC/AC difference 0,01 % to 20 kHz.

Measurement of DC, AC or pulse currents. Reference for other current measuring devices. Measurement of firing pulse of electric detonators.

Precizni strujni shunt

Current shunt SB 101, 2 pieces

Max. current 30 A,
resistance 3.33 mΩ.
Accuracy 0.5 %.

Measurement of DC, AC or pulse currents. Measurement of firing pulse of electric detonators.

Strujni shunt

Wideband Current Transformer 2-0.1W

Output (V/A) 0.1. Accuracy 0.5 %
Max. current peak 5000 A. Max. rms AC current 65 A. Rise time
20 ns. Frequency 1 Hz – 20 MHz.

Measurement of electric current, powers (P, Q, S) and power factor of monophase load can be calculated. Measurement of high voltage conductor currents.

Strujni transformator

Wideband Current Transformer model 6600

Output (V/A) 0.1. Accuracy 1 %
Max. current peak 2000 A. Max. rms AC current 40 A. Rise time
5 ns. Frequency 25 Hz – 120 MHz.

Measurement of electric current, powers (P, Q, S) and power factor of monophase load can be calculated. Measurement of high voltage conductor currents.

Sirokopojasni strujni transformator

Wideband Current Transformer model 6585

Output (V/A) 0.1. Accuracy 1 %
Max. current peak 500 A. Max. rms AC current 10 A. Rise time
1.5 ns. Frequency 400 Hz – 250 MHz.

Measurement of electric current, powers (P, Q, S) and power factor of monophase load can be calculated. Measurement of high voltage conductor currents.

Sirokopojasni strujni transformator

Current Transformer MSZ 1576, 10 pieces

Measurement ranges 15 A, 50 A, 100 A, 200 A, 300 A, 400 A, 600 A.
Accuracy 0.2 %

Measurement of rms AC currents.

Mjerni transformator

Multichannel Arbitrary DC Power Supply Unit HM8143

Two outputs (0 V– 30 V)/2 A and output with fixed voltage
5 V/2 A.
Two outputs can work as amplifier with amplification of 3.
One channel can work as signal generator (12 bits/4096 points) with output current <2 A.

Power supply of loads or sensors/transducers that need regulated voltage or current for operation.

Visekanalno upravljivo DC napajanje

High voltage DC power source MK40P1.8.

Type MK, up to 40 kV (5 % to 100 %), 75 W, 1.8 mA.

For Detonator sensitivity testing to high voltage disharges.

Viokonaponski izvor

Stereo sound and noise recorder TASCAM US-122

Sample rate 48 kHz, 24 bit resolution,
16 MIDI I/O channels.

Sound or noise signals recording which enables saving data to the computer and later analysis.

Uređaj za dvokanalno snimanje zvuka

Measurement condenser microphone ECM 8000, 2 pieces

Impedance 200 ohms,
sensitivity 70 dB,
freq. response 20 Hz – 20 000 Hz,
phantom power +15 V to 48 V,
gold plated XLR connector.

Omnidirectional ultra linear microphone for measurement and recording applications.

Mikrofon
Teaching in the laboratory

 Teaching in the laboratory (students' practical work) in 2016/2017

Course title

Mandatory or Elective course

Number of hours of practical work in lab

Number of students per group

Number of groups

Fundamentals of Electrical Engineering

Mandatory

16

12

4

Fundamentals of Electrical Engineering

Mandatory

16

12

4

Fundamentals of Electrical Engineering

Elective

4

12

2

 Electrotechnology in Mining

Mandatory

8

10

2

 Measurement Technology

Elective

12

6

1

Teaching in the laboratory (Students scientifice research)

 

Teaching in the laboratory in 2016/2017 (Students scientifice research)

Name and surname of student

Tesis title

MSc thesis

Ivo Žilić

Inertization

 

BSc thesis

Hana Stipanović

Measurement of mass and calibration of scale

 

Dominik Marija Rebić

Development of precision reference oscilator

 

Matej Ereiz

Testing of self-heating of coal briquette

 

Nikola Bodružić

Determination of rock linear temperature coefficient

 

Projects in the laboratory

Projects in the laboratory in 2016/2017 

Scientific research (including University support)

Expert projects

 Surface exploitation system optimization through increase of energetic efficiency

PEX seminar OB4 (17. i 18.11.2016.), T71E (13. - 17.2.2017.), OB5 (23. i 24.2.2017.), OB6 (16. i 17.3.2017.), OB7 (18. i 19.5.2017.), OB8 (7. i 8.9.2017.) i T72E (18. - 22.9.2017.)