The answer is: They are not. Whosoever told you that is off his meds. Alternatively, in some special applications there may be a reason for it. Many DC systems use a common ground where the loads are encased in the ground (like starter motors). Thus all breakers are positive, but some don't. If the loads don't care about polarity and the positive and ground are not common (like with a metal chassis), positive and negative is irrelevant.
DC Bridge... We use DC supply, Detector is also a DC current detector and we use only resistive components no need for wegner's earthing device balancing time is comparatively less.. where as in AC bridges opposite of above. i.e. AC supply, AC current detector resisitive+ reactive componants need for wagner's earthing device and balancing time is high as we use AC supply..
i dont know use rectifier just invert ac to dc and supplied to anodes positive to steel negative
(the current in the earth direction is going left of use) 8th grade studend juicey babee
Your question is better expressed as why can an ac circuit be shorted to earth when a dc circuit can't be? With an ac supply only the positive feed is actually present at the socket. There is no negative, just a neutral return which is actually connected to earth at the power station / substation. Earthing an ac curcuit just provides a shorter route to the earth, which is where it would have gone anyway. The earth connection at the socket is just to provide a safe means of dumping the current locally in the event of a fault. In a dc circuit the current has nowhere to go, other than to the negative terminal / rail. Without both positive and negative being present no circuit can be formed.
Mostly for small dc motor, 2core are used. earthing can be achieved by grounding the chassis.
yes it does... thanks for asking...
In a 48V DC system you ground the positive to 0V so the live wire will be -48V.
We can use DC too for the transmission system. Refer HVDC transmission system.
Yes, the electrical code states that all electrical equipment must be grounded.
The answer is: They are not. Whosoever told you that is off his meds. Alternatively, in some special applications there may be a reason for it. Many DC systems use a common ground where the loads are encased in the ground (like starter motors). Thus all breakers are positive, but some don't. If the loads don't care about polarity and the positive and ground are not common (like with a metal chassis), positive and negative is irrelevant.
DC Bridge... We use DC supply, Detector is also a DC current detector and we use only resistive components no need for wegner's earthing device balancing time is comparatively less.. where as in AC bridges opposite of above. i.e. AC supply, AC current detector resisitive+ reactive componants need for wagner's earthing device and balancing time is high as we use AC supply..
green is ground regardless of ac or dc
Brown
If it is DC then red is positive and black is negative.
In an electrical system, the positive terminal typically connects to the higher voltage side of the circuit, providing the potential difference needed to drive current through the system. It is often associated with the flow of electric charge from the positive terminal to the negative terminal in a circuit. In direct current (DC) systems, the positive terminal is usually marked with a "+" sign, indicating its role in powering devices or components.
A well known application of a microelectronic system is the AC to DC converter. If, for example, you wanted to take electricity from a wall outlet you could use 4 diodes a resistor and a capacitor of correct values to change it into a DC current.