High Resistance Grounding Systems (HRG) are used that are limit the fault current up to 5 – 10 A at hospitals, data centers, textile plants, cement plants and other facilities that manufacture with injection to ensure continuity of system. These systems are designed to withstand the fault current continuously.
When determining the fault current in the HRG system, it is necessary to take into account the capacitive currents and leakage currents flowing from the neutral to the ground due to the capacity of the cables. If the failure current is lower than the zero sequence current, HGR system runs in failure mode and cannot function.
HRG systems are optimum solutions from 400 V to 6.9 kV medium voltage system. One of the most important features of HRG systems is the possibility of detecting the location of the fault. When a phase-to-earth fault occurs in the network, the HRG system automatically reduces the resistance value by half, so as to flow twice the rated fault current for 1 second (E.g. 1 second 5A, 1 second 10 A). In this way, the fault current changes in such a way that the current can be easily detected even in high phase current and the currents of the outputs in the distribution panels are controlled with the help of a simple clamp meter and fault location is determined.
In contrast to other systems, Aktif HRG systems automatically detect the location of fault. In the active control panel of the Aktif HGR, if there is a fault in the operation, it is automatically displayed from which distribution point of the fault and from the load which is connected to that distribution point. If the switching equipment used at the plant have the ability to receive the external interrupt signals, the source of the failure can be deactivated.
Also, Aktif HRG systems automatically monitor and confirm that the system is functional. In case of a system failure, visual and audio alarms are sent to the user. Thus, it maximizes both its own an operational safety .
Advantages
- Limiting the short circuit failure current
- Detecting the location of the fault
- Monitoring the system operation
- Visual and audio failure notification
- Stable fault and pulse current with 3% resistance variation against temperature rise
- Modular and rigid enclosure design with resistor blocks mounted to the frame for safety lifting
Application Areas
- Any area where energy continuity is priority like
- Electrical network
- Hospitals
- Data centers
- Textile factories, Cement factories
- Nominal voltage up to 7,2 kV
- Suitable for continuous current up to 10 A and impulse current up to 20 A
- Adjustable fault current, impulse time
- Smart fault detection system
- Smart auto control system to check system operation
- Current and voltage monitored on the panel
- Stainless steel resistance material suitable for extreme ambient conditions, resistant to oxidation and corrosion (AISI304, AISI310, AISI316, AISI430, CrAl, CrNi)
- Special mechanical and electrical design to withstand high temperature and extreme current values
- Design and testing in accordance with IEEE C57.32 standard and special specifications
- Spring-wound, edge-wound or grid resistor elements with a cross-section suitable for the nominal current
- Standard IP23 protection level
- Standard painted enclosure
- Lockable door with hinges
Type | Size | Download Link | |
GR - Neutral Grounding Solutions | 1 MB | Download |