ELR Installation at Traffic Control Building

Supply and Installation of 04 Nos of ELR ( Earth Leakage Relay ) in SMDB at First Floor in Traffic Control building to the outgoing breakers each were of 100 Ampere MCCB of Schnider Electric( Same as Merlin Gerin)

Material Bought from - Safety Electrical

Material

1. Shut Relay
2. ELR
3. Fuses
4. CBCT ( We bought it for 50mm2 cable because Lugs were connected so small can't enter in side the cable)

Fixed the shut inside the breaker assembly , put the CT's on the cable , installed ELR on rail mounted c-channel and made the wiring

How Basically It Works

ELR Earth Leakage Relays along with CBCT are used to detect
leakage  current in the earthing. If the earthing is not
proper a small amount of current will appear (in the order
of mA). ELR will continuously monitor the leakage current
if it exceeds the set threshold an output electromechanical
relay (which is inside the ELR) will operate. The output
relay contact can be connected to circuite breakers /
contactor to isolate power supply or alarms.

CBCT Core Balance Current Transformers these will come in
different sizes. the core material will be either nickel or
alloy of nickel, copper wire will be wounded on the core
and properly insulated. The 3-phase line along with neutral
are passed in this core and secondary is connected to ELR.
Idealy the leakage current should be zero if any earth
leakage happen the leakage current will appear at CBCT
secondary it will be detected by ELR