If there is a short circuit between the transformer's high-voltage windings and its core (or any other metal parts, come to that) the fault will be recognised by the high-voltage supply's protective system, which will quickly disconnect the high-voltage line. For this to happen, the metal parts of the transformer, including its core and metal container, must be earthed or grounded to provide an electrical path back to the source of the high voltage.
The secondary of a CT should (must) be grounded because, otherwise, it would develop high voltage across it, potentially damaging equipment and/or injuring or killing someone.
No load current is energizing current. This is effectively "lost" power, power used in the transformer to energize the core. It, therefore, should be small!
If the number of turns in the primary is the same as the secondary, this would be an isolation transformer. Primary and secondary voltages should match (minus the inherent transformer losses), as should the current.
Hertz Hurts
Yes, a transformer has eddy currents.
When the secondary of a transformer is opened, there is no longer any load on the transformer. There will be some current flowing in the primary winding, which is needed to induce the voltage in the secondary. This primary current is referred to as the "no load" current, and is indicative of the core losses in the transformer.
A transformer doesn't 'conduct current through the ground'. However, in the event of a ground fault in the circuit supplied by a grounded transformer, the resulting fault current will flow through the earth back to the grounded terminal of that transformer's secondary winding.
A transformer can be used to change the voltage to an appliance. The voltage rating of the transformer should be right for the voltages used, and the current rating of the transformer should not be less than the current drawn by the equipment.
Yes. Yes, you can replace a transformer with one that has a higher current rating. The load on the transformer should be less than 200mA because presumably that is what the circuit was designed for. Since the current through the transformer should be less than 200mA, the 500mA transformer will not be damaged. The opposite is not true. You should not replace a 200mA rated transformer with a 100mA transformer, for example. If the current exceeds 100mA, the transformer could fry.
No load current is energizing current. This is effectively "lost" power, power used in the transformer to energize the core. It, therefore, should be small!
There is no 'standard' output current from a transformer. The secondary (output) current depends on the load, and should not exceed the rated secondary current. To find the rated secondary current, you divide the transformer's rated volt amperes by the rated secondary voltage. The above cited answer need more descriptive ; a) V/Z = I, b) V/Z = I + Magnetizing current of the transformer taken from Primary side of the transformer.
What should happen is that the circuit-breaker should trip to cut off the current before the transformer becomes damaged by overheating.
The transformer cannot be used in the DC supply because it keeps on alternating its current, whereas the DC supply current should be constant.
Secondry of CT should never kept open during functioning
the incoming voltage from the current source to the transformer is called primary voltage.....
in welding machine, the transformer used is basically a current transforrmer. so by changing the tap of secondary side of transformer, we can increase or decrease the current in the transformer.
why does have to short-circuit secondary wire of current transformer ?
The difference between current transformer and potential transformer is that the secondary of a current transformer can not be open circuited while under service whereas that of the potential transformer an be open circuited without any damage to the transformer.