0
Electrical Wiring
Ask questions here about proper wiring and electrical installation here.
4,935 Questions
What is used to indicate when a desired angle has to be made?
A protractor will indicate an angle that has to be made.
What is electrical single-phasing?
On a three phase system, when one of the leg fuses opens due to a fault current on that leg, the system is said to be single phasing.
What is the difference between an RC CB and an EL CB?
An RC CB is a Residual Current Circuit Breaker. It is another name for something more commonly known as an RCD (Residual Current Device). An EL CB is an Earth Leakage Circuit Breaker. It is another name for something more commonly known as a GFCI (Ground Fault Circuit Breaker). For more information on these electrical safety and circuit protection devices please see the answer to the Related Question shown below.
What does the points X N L1 and L2 mean in the defrost timer?
In electrical terms X usually refers to a transformer's secondary terminal output. Example X1, X2, X3, and X4. If the timer is a clock defrost timer then the X represents a point where the timer release relay connects to.The letter N represents the neutral conductor. On controls it should be a white wire.
L1 represents a line conductor which means a "hot" wire. From L1 to N the voltage applied should be 120 volts.
L2 is a second line conductor, the voltage applied across L1 to L2 should be 240 volts.
Piese de resistance is a French term meaning almost the same thing in English, piece of resistance pertaining to something as "the best part".
BIL is basic insulation level as per you or in other words it would be "basic impulse level" which implies the limit up to which an insulator could withstand impulse due to lightning strikes. Impulse is generated on the insulation due to the high voltage surges and spikes due to lightning strikes. BIL is generally much higher as compared to power frequency withstand voltage.
In other words BIL is lightning Impulse withstand voltage. Impulse withstand voltage is the voltage that is generated due to switching operation and it's much higher than power frequency withstand, but BIL or the lightning withstand voltage is a the voltage level that an insulation can withstand during surge or lightning strikes.
well, it depends on what the other stand says
if it's 1 and 0, then 0 would be off
most of the time o or 0 will mean off
Why would four core armoured cable be used in a single phase circuit?
Four core armoured cable would be used in a circuit carrying 240 Volts 60 Hz AC that is installed in a location where it could get damaged, such as underground or under water. The 4 cores in the armoured cable would be used as the following conductors for the 240 V 60 Hz circuit: * "Red" hot (120V above Neutral)
* "Black" Hot (120V below Neutral)
* "Neutral"
* "Ground" to protect the circuit, connected to the main incoming supply panel which feeds the circuit.
Can you use MCCB instead of fuse in a three phase connection?
Yes, three phase CDP (Central Distribution Panels) all use breakers to distribute the three phase supply voltage to their respective loads.
Why use 16mm cable for earthing?
A large cable for earthing is to allow for the possibility of a very large current which would melt a smaller one thus removing the protection it is supposed to provide.
How do you splice a ground wire?
Strip the wires back about 3/4" and then using lineman's pliers twist the wires together about 2 turns. Tighten a wire nut securely to the connection. Then tape the splice securely with electrical tape.
Why is less resistance for a conductor wire good?
Resistance in a wire restricts the movement of the electrons through the wire. This restriction transfers some of the energy contained in the electrons into the material of the wire and as this energy accumulates in the material of the wire the wire starts to heat. Therefore, there the energy that is transferred into the wire material is considered wasted because it is not available as electrical energy, which means the consumer who is using that wire is charge for the electrical energy that is waste. It the resistance is less in that conductor the consumer will save money.
A relay is an electrical switch. It consists of a electromagnetic coil and a set of mechanical contacts. Depending on the relay their could be multiple sets of mechanical contacts.
The close contact lets current flow through the mechanical contacts when the relay is not turned on. When the relay is turned on current flow is stopped. This is called a normally closed contact or NC
The open contact works the opposite of the closed and is referred to as a normally open contact or NO
What is oscillatory discharge?
Alternating current of gradually decreasing amplitude which, under certain conditions, flows through a circuit containing inductance, capacitance, and resistance when a voltage is applied is known as Oscillatory discharge.
the wiring caught fire at the fire wall going into the cab....not sure why...no damage interior hood...just isolated to fire wall area...what needs to be done?
Why used star contactor half value then main and delta contactor in star delta starter?
This type of motor starting configuration is used to start large motors. The utility company's policy is to only let a certain three phase motor horsepower loads across the line starting. High horsepower loads draw high current which draws the line voltage down. This causes a small instantaneous brown out to which the utility company gets complaints about. To solve this problem, limit the horsepower load. Starting a delta motor in star configuration reduces the inrush current because the voltage applied to the motor is lower.
This technology is rapidly becoming old due to the new type of motor controllers on the market. Replacing the star delta starters is soft start controllers. The inrush current can be controlled so as to not make any voltage drop on the line. These controllers are different from VFD's which are expensive for this type of application. The main function of the soft start is to get the motor on line without any line disturbances.
What will happen if a phase and neutral test by a mutimeter shows continuity?
If the test shows that there is a continuity between the phase leg and the neutral with no load connected, then that circuit should not be energized. If the circuit was energized then the fuse or breaker protecting that leg will trip the circuit open.
You have 3 sets of conduits with 6 500MCM conductors in each one what is your ampacity?
The ampacity of 500 MCM R 90 degree wire is 395 amps. Don't forget to de-rate the wire as there are more that three conductors in a raceway.
How do you test the output of a household AC electrical power adaptor?
First, always read the label on the power adaptor to find out what voltage it has been designed to supply.
You can use a volt meter or a 12v light bulb to check if the power adaptor is working but don't do this unless you are certain that the output voltage really is a low as that!
If you don't check the label first you could damage the volt meter or the bulb and/or give yourself a dangerous shock.
Another more technical answerFirstly, using a voltmeter to check that the output voltage is as specified on the label. An unregulated power adapter will usually have an output voltage somewhat higher than the voltage specified when measured using the meter alone, but will drop to nearer the required voltage when measured under a significant load. A regulated power adapter should give a fairly constant voltage reading when tested with or without a load applied. Second, using an oscilloscope to see if there is any significant "ripple" in the output voltage, the presence of which would indicate a faulty smoothing capacitor inside the adapter.What is the principle frequency reuse in the context of a cellular network?
Adjacent cells are assigned different frequencies to avoid interference or crosstalk. The objective is to reuse frequency in nearby cells. 10 to 50 frequencies are assigned to each cell. Transmission power is controlled to limit power at that frequency escaping to adjacent cells. The issue is to determine how many cells must intervene between two cells using the same frequency. Adjacent cells are assigned different frequencies to avoid interference or crosstalk. The objective is to reuse frequency in nearby cells. 10 to 50 frequencies are assigned to each cell. Transmission power is controlled to limit power at that frequency escaping to adjacent cells. The issue is to determine how many cells must intervene between two cells using the same frequency. Adjacent cells are assigned different frequencies to avoid interference or crosstalk. The objective is to reuse frequency in nearby cells. 10 to 50 frequencies are assigned to each cell. Transmission power is controlled to limit power at that frequency escaping to adjacent cells. The issue is to determine how many cells must intervene between two cells using the same frequency.
