Two separate and one distinct earth connection is required for the motor frame as per IE rule 61.
Q. Which 50V to 100v alternating current systems are not required to be grounded?
Section 250.21 focuses on alternating-current systems of 50V to less than 1,000V that are not required to be grounded. As outlined in 250.21(A) and (B), ground detectors are required for these systems and they shall be connected as close as practicable to where the system receives its supply. Voice your opinion!
Q. Why are two earth wires connected to metallic frame of motor?
EQUIPMENT EARTHING The non-current carrying part of the equipment like their metallic frame is connected to the earth by the help of the conducting wire. If any fault occurs in the apparatus, the short-circuit current to pass the earth by the help of wire. Thus, protect the system from damage.
Q. Why is Earth wire used?
Earthing is used to protect you from an electric shock. It does this by providing a path (a protective conductor) for a fault current to flow to earth. It also causes the protective device (either a circuit-breaker or fuse) to switch off the electric current to the circuit that has the fault.
Q. Does a ceiling light have to be earthed?
Any light, lamp, bulb holder or fitting with a conductive or metal exterior surface must always be earthed to ensure against risk of electrocution or serious injury. We recommend that any fitting or installation is done by a qualified electrician, do not risk installation yourself if you are at all unsure.
Q. Are lighting circuits earthed?
Current regulations require an cpc on the lighting circuit. This is not retrospective and means that you do not need to have one on an existing lighting circuit. This does mean that no lighting or other electrical device that requires connection to earth cannot be used on the lighting circuit.
Q. Can you borrow an earth from another circuit?
no. borrowing a earth from some where else . it will cause problems down the line if was a main fault .
Q. Will RCD work without earth?
Since the Earth is not part of this sensing, technically the RCD can protect without an Earth. If a person contacts the Active (A) wire and a dangerous current flows thru that person to ground, the RCD senses an imbalance between A and N and trips out.
Q. How long can a lighting circuit be?
cable will be used for lighting. A lighting circuit can serve up to 12 x 100W bulbs. Using 1mm cable is allowed for up to 95meters of circuit length. This does not include the light switches which should be wired in switch wire which contains 2 red cores.
Q. Can I use 2.5 cable for lighting?
You can use 2.5 mm² cable of course. In large buildings sometimes 4 or 6 mm² cable is used on the feeder runs, and near the light fittings the cables are branched off in J-boxes to 1.5 mm² to go to the light fittings, to compensate for voltage drop. These light circuits are often controlled through contactors.
