How to connect earth leakage relay
The wiring method of the leakage relay varies depending on factors such as load type and power supply properties. This article will introduce the earth leakage relay wiring diagram and provide the corresponding wiring diagram.
Typical earth leakage relay wiring diagram
Earth Leakage Relay body: The figure shows a leakage protector with an LCD screen, which can intuitively display the leakage current value and setting parameters.
Terminals: There are multiple terminals on the leakage protector, which are used to connect the power line and the load line.
Power line:
Phase line (A, B, C): The three-phase lines connected to the power supply.
Neutral line (N): Connect the neutral line of the power supply.
Load line: The wiring method of the load line is similar to that of the power line. Connect the phase line and neutral line of the load to the corresponding terminals of the leakage protector respectively.
How to connect earth leakage relay In TNS-System
TN-S describes an arrangement where separate conductors for Protective Earth (PE) and Neutral are run to consumer loads from a site’s power supply (i.e. generator or transformer). The PE and N conductors are separated in nearly all parts of the system and are only connected together at the supply itself.
In a TNS system, the neutral (N) and protective earth (PE) conductors are separate throughout the network, ensuring effective fault current management. To connect an Earth Leakage Relay (ELR), the phase (L) and neutral (N) conductors are passed through a Zero-Phase Current Transformer (ZCT), while the PE conductor remains outside. The ZCT detects leakage currents, and the ELR triggers a circuit breaker to disconnect the supply when necessary. This setup ensures enhanced safety by quickly isolating faults, protecting both equipment and personnel.
How to connect earth leakage relay In TT-System
In this sort of Earthing System, the connection to the supply source is connected directly to the earth, and the load end or installation metalwork is also directly connected. As a result, in the case of an overhead line, the earth’s mass will serve as the line’s return path.
Because the power distributor only offers the supply neutral or protective conductor for the connection to the consumer, the neutral and earthing conductors must be separated during the installation.
How to connect earth leakage relay with MCCB
Earth leakage relays can sense the earth leakage current and sends signals to the circuit breaker to trip the circuit or disconnect the main power supply. Earth Leakage fault occurs due to improper connection, insulation failure, moisturization in electrical circuits, human electric shock, etc. Generally, in most of the industrial electrical wirings, panels earth leakage relay is used to protect electrical devices and equipment. Earth leakage relay is always used with a circuit breaker(MCCB, ACB, etc). So when an earth leakage fault occurs, the earth leakage relay can sense the fault and send the signal to the circuit to trip the main power supply.
By properly connecting an ELR, you can enhance the safety and reliability of your electrical system, minimizing the risks of electric shocks and equipment damage caused by leakage currents.
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