Grounding Measurements
What is Grounding Measurements ?
There is grounding system in industrial areas and buildings. Measuring this system is crucial to preventing possible hazards. This measurement is called grounding measurement. These checks need to be done at least once a year. Controls and measurements are carried out within the scope of Electrical Facility Grounding Regulation and Occupational safety. In this measurement, concepts such as ground electrode and specific resistance are important. The technical inspection to be carried out is carried out in accordance with the contents of these concepts.
Grounding measurement and control; The Electricity Plant Grounding Regulation and the Electricity Internal Facilities Regulation and the Use of Work Equipment are carried out within the framework of the Health and Safety Requirements Regulation and the Regulation on Health and Safety Measures in the Workplace Building and Add-Ons.
It is a system that needs to be grounded and checked annually within the scope of earthing measurement and electrical indoor installation control.
It is recommended to repeat this work once a year, and the grounding installation should be periodically inspected and measured by authorized electrical engineers at least once a year, for replaceable machines and devices, every six months.
How is Grounding Measurement done?
Electrical Grounding Measurement, Control, Inspection, Measurement and Supervision
As explained in the article 10-A of the regulation, the grounding system should be regularly checked during installation or during the operation period.
If we exemplify a few of the controls and measurements that need to be made;
- Measurement of soil specific resistance,
- Control of current protection (RCD) pattern now,
- Measuring and controlling the insulation resistance of the electrical facility,
- Visual inspection,
- Measuring and controlling the continuity of protection conductors, main and complementary potential compensation conductors connections,
- Control of loop impedance,
- Measuring grounding resistance
- Checking whether the feed is cut automatically
What Should Be the Grounding Measurement?
Grounding regulation should be calculated with the boundary value formula. Panels, machines are measured by looking at the value of each socket’s fuse or residual current relay. It is wrong to mention a fixed value when measuring or evaluating the ground resistance value. It is necessary to act according to the following variations.
Residual current relay 30 mA. if available, 50 V./0,03 A = 200 ohms limit value.
Residual current relay 300 mA. if available, 50 V./0,3 A = 80 ohms limit value.
No leakage relay and if the main switch has a thyroid; 1 A. is the limit value of 50 V./1A=50 ohms.
If there is no residual current relay and there is no thyroid in the main switch, the measurement is taken from the fuse value.
No leakage relay and if there is no thyroid in main switch, fuse
If we consider the Class B 25 A, 50 V. / 5 mm 25 = 0.4 ohm limit
value.
