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For a perfectly balanced load, with identical loads connected between each line conductor and the neutral conductor, there should be no neutral current. This is because the vector sum of three identical current, displaced by 120o, is zero.
However, for an unbalanced load, there will always be a neutral current because the vector sum of the currents will not cancell.
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How you can check load connected of transformer?
Measure the current and voltage on the secondary side.
Do all electrical power sources flow to earth e.g. Secondary winding of an isolating transformer with no earth connection on the neutral line?
There are situations where the secondary of a transformer is not grounded and the neutral is not connected to the neutral of the primary. This can cause a potential shock hazard so the secondary side needs to be protected.
Why instruments are connected on low voltage side of the transformer while performing no load test?
since we need to get desired or rated voltage, so if it is connected in high voltage side of the transformer, voltage supply will be more, and hence the current will be more than the required amount. this is the reason why the instruments re connected at the low voltage of the transformer while performing no load test.
What is the standard output current of a transformer when connected to an ac?
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.
Why load is always connected to secondary of transformer?
b'coz at the secondary side large amount of current flow by recarding of active component or other ckt. which is connected to the secondary side so that ckt. is not damage or burned by flowing large amount .. load is connected at the secondary side .AnswerThe 'primary' winding of a transformer is, by definition, whichever winding is connected to the supply, whereas the 'secondary' winding is whichever winding is connected to the load. This does not mean that a load MUST be connected to a transformer, as it will work 'off load' -that is, with no load connected- without any harm.
How you can check load connected of transformer?
Measure the current and voltage on the secondary side.
Do all electrical power sources flow to earth e.g. Secondary winding of an isolating transformer with no earth connection on the neutral line?
There are situations where the secondary of a transformer is not grounded and the neutral is not connected to the neutral of the primary. This can cause a potential shock hazard so the secondary side needs to be protected.
Why instruments are connected on low voltage side of the transformer while performing no load test?
since we need to get desired or rated voltage, so if it is connected in high voltage side of the transformer, voltage supply will be more, and hence the current will be more than the required amount. this is the reason why the instruments re connected at the low voltage of the transformer while performing no load test.
What is the standard output current of a transformer when connected to an ac?
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.
Why there is zero volt across neutral earth of isolation transformer?
Geez, because it is just that; A NEUTRAL EARTH, there should be equal potential on each side, therefore no current flow, and no voltage.
Why load is always connected to secondary of transformer?
b'coz at the secondary side large amount of current flow by recarding of active component or other ckt. which is connected to the secondary side so that ckt. is not damage or burned by flowing large amount .. load is connected at the secondary side .AnswerThe 'primary' winding of a transformer is, by definition, whichever winding is connected to the supply, whereas the 'secondary' winding is whichever winding is connected to the load. This does not mean that a load MUST be connected to a transformer, as it will work 'off load' -that is, with no load connected- without any harm.
How relay used for protection purpose?
Relay are operated by small current /voltage connected to Secondary side of Current Transformer and /or Voltage Transformer. The signal stimulates the magnetic substance nearby with the attracting force. This closes or opens the circuit being used in protection purpose.
How do you carry short circuit test on power transformer?
For carrying Short Circuit Test on Power Transformer Do the following: 1] Isolate the Power Transformer from service. 2] Remove HV/LV Jumps and Disconnect Neutral from Earth/Ground. 3] Short LV Phases by Cu/Al plate which could withstand short circuit current and connect these short circuited terminals to Neutral 4] Energise HV side by LV supply (440 3ph Supply) with OLTC tap position on Normal. 5] Measure Current in Neutral, LV line voltages, HV Volatage and HV Line Currents on various OLTC Tap position. Analysis: If Neutral current is near to zero transformer windings are OK If Neutral current is higher or equal to Line current between LV Phase one of the winding is Open.
Is transformer side interchangeable?
yes,we can change the transformer side in transmission line as use of high current or high voltage in output.
Why on load or off load tap changer is always connected in the primary side of a power or distribution transformer. And why distribution and power transformer are rated MVA?
The size of any switch depends on current it carries. Your statement is true for step down transformers. The primary is HV hence less current, so the tap changer is on primary side.
How would one wire up an earth leakage circuit breaker on the secondary side of an isolating transformer?
Isolation transformers are used to protect people working on transformerless equipment, where there is a 50-50 chance that the equipment's metalwork is at mains active voltage (110/240 V). Plugging in to the transformer "floats" the equipment, so that the metalwork can be safely connected to ground, and remove any voltage on it. An ELCB relies on detecting the imbalance between active current and neutral current that occurs when you touch a wire of metalwork that's at mains potential. But, on the secondary of the isolation transformer, you decide which is active and neutral. It is possible to wire the ELCB into circuit on the secondary side of the transformer, just as you would for a normal installation. Be aware that you must now connect one of the transformer secondary wires to gound for the ELCB to work (at least, that's the case here in Australia), so you are back into the 50-50 chance of live metalwork, unless you fit a reversing switch that lets you ensure that the metalwork is connected to neutral. But you need to understand that an ELCB only protects you from active-to-ground shocks, it DOES NOT protect you from active-to-neutral shocks, and there is no current equipment that can. I STRONGLY SUGGEST that you consult with a licensed electrical contractor to work out what you are trying to achieve. Electricity gives you one chance.
What does the term primary side refer to?
The line side of a transformer that is connected to your source or incoming voltage that you are stepping up or down.
