Current difference between phase and neutral conductors in electrical lines oIn case of contact, the switch is intended to protect the line by opening the circuit, residual current protection relay It called. Active electricity In the circuit, the current entering from the phase line comes out through the neutral line. Under normal conditions, if there is no leakage in the circuit, the amount of current entering and leaving is equal to each other. However, in case of any leakage in the circuit, all of the current entering from the phase line will not come out of the neutral but some of it will come out of the part where the leakage is, and in this case, the phase-neutral equation will be broken. Used on power lines residual current protection relay it detects this inequality and opens the circuit and prevents any negative effects due to leakage current.
According to the experience gained during the tests and maintenance stages; most of the electrical leakage occurs as a result of fraying, crushing or breaking of the insulators located outside the conductors where the electrical current passes. In addition, incorrect insulation techniques are another factor in the formation of leakage currents.
In such a case, contacting the boards, lines or machines with the leakage current may cause electric shocks, as the leakage current will attempt to flow to the ground in the shortest way in order to complete the circuit. For this reason, it is important to take the necessary precautions when approaching electrical lines or electrical machines in order to prevent vital risks.
Leakage current relays are activated in case the current does not discharge with the ground line due to any problem in the electrical system and cut the line to prevent possible dangers. Because, especially in the following two cases, leakage currents occur in the electrical installation:
- Grounding resistance is too high
- If the cables connected to the ground line come into contact due to insulation faults
Leakage currents must be prevented and kept away from electrical installation in order to avoid any danger. Otherwise, it can create a danger to life and property safety. Leakage current relay is based on the difference between phase and neutral. A residual current relay with a value of 30 mA automatically switches off the electrical current if the current difference between the phase and neutral is above this value. That is, if the difference between the value of the current passing through the phase line and the value of the current passing through the neutral line is above the protection value of the leakage current relay, the electrical connection is disconnected.
In the event of an electrical leakage and any short circuit, fuses used in homes and workplaces also come into play. But if you think that the smallest fuse used is 6 ampere, this value is much higher than the limit value for people's health 30 mA and it cannot be said that the fuse is fully protected against human safety. Because of this reason, leakage current relays provide complete protection in terms of health and property safety.
Authorized control and inspection organizations and laboratories also perform leakage current measurements. In these studies, while measuring whether there is leakage current on the existing electrical installation, leakage current relays produced are tested.
Our company also conducts electrical leakage protection measurements in accordance with the relevant legal regulations, standards and test methods published by local and foreign organizations within the framework of electrical safety inspections. A few standards considered in this regard are:
- TS EN 61008-1 Residual current circuit breakers - Without integral overcurrent protection - Used in domestic and similar places (RCCB) - Part 1: General rules
- TS EN 61008-2-1 ... Section 2.1: Applicability of general rules to RCCBs independent of line voltage as a function
