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Three phase voltage can be measured in star, each leg to neutral, or in delta, each leg to a different leg. Assuming that neutral is balanced in the center of the phase triangle, the star voltage is the delta voltage divided by 1.732. 1.732 is the square root of 3, and comes from the phasor analysis of three phase power.
For instance, a typical three phase distribution line at 13.2 KV delta, is 7.62 KV star.
Another example is that if you know the winding current in delta, the phase current is 1.732 times the winding current.
a dc ammeter is a ammeter which has three pins and it works by two wires.
This is too complicated to describe on this forum, but there are lots of web pages that describe the 'three-ammeter' method of measuring power, so your best plan is to visit one of those sites.
I am assuming that you really want to use ammeters to measure power in a balanced 3 phase system. (hope you are not meaning 3 watt meter method) Power in Watt in a three phase system is equal to 1.73 x line voltage x line current x power factor. You need to know line voltage, power factor also in addition to current to compute the power. If the system is balanced then actually you do not need to connect ammeters in all three lines. One ammeter reading will do.
You use three CTs, one per line conductor, each feeding a separate ammeter,
An ammeter measures current, an important variable in electronics.
single phase power measure by three ammeter method
a dc ammeter is a ammeter which has three pins and it works by two wires.
This is too complicated to describe on this forum, but there are lots of web pages that describe the 'three-ammeter' method of measuring power, so your best plan is to visit one of those sites.
dc ammeter has three connecting pins while ac has four
There is no formula for finding anything - except perhaps the inevitable "where was it when you last saw it?"
we can measure the resistance of the motor by using voltmeter ammeter method of by directly using a multimeter across the armature terminals of the motor in voltmeter ammeter method we should use a less value of dc voltage to find the resistance
Voltmeter, ammeter, wattmeter.
I am assuming that you really want to use ammeters to measure power in a balanced 3 phase system. (hope you are not meaning 3 watt meter method) Power in Watt in a three phase system is equal to 1.73 x line voltage x line current x power factor. You need to know line voltage, power factor also in addition to current to compute the power. If the system is balanced then actually you do not need to connect ammeters in all three lines. One ammeter reading will do.
You use three CTs, one per line conductor, each feeding a separate ammeter,
if we take resistance in parallel with ammeter then the range of ammeter will change.
An Ammeter and a brick is a brick.
ammeter real picture