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What else can I help you with?
Why three phase meter is better than single phase meter?
A three-phase meter can be used for single phase while the reverse is not the case.
Do you change the high leg if your three phase motor is running in reverse?
yes
What is the difference between single phase and three phase voltage measurement?
Phasing, or the number of phases in an electrical system has nothing to do with the voltage. A single phase and three phase supply could have a voltage supply of any given voltage from virtually 0 to infinity. Most single phase power supplies in the US are 120/208-240 volt. Three phase power supplies are typically 120/208 to 277/480 volt.
What will happen if we use current transformer of different rating for each phase in three phase supply?
A current transformer has to have the same ratio as the meter that it drives. Full scale deflection on the meter is 5 amps which equals the maximum allowed current on the phase that it is reading. A different ratio on the CT to meter would show an erroneous reading on the meter depending on the ratio of the connected CT. To keep costs down the meter is common to all three phases and is read by connecting the meter to the phase CT through a three position switch.
How do you change rotation on a Century AC motor?
There are two alternate methods depending on whether the motor is single phase or three phase. On a single phase motor, reverse either the start winding coil lead or the run winding coil lead but not both. This action will reverse the motor's rotation. On a three phase motor, interchanging any two of the three coil leads will reverse the motor's rotation.
Why three phase meter is better than single phase meter?
A three-phase meter can be used for single phase while the reverse is not the case.
Do you change the high leg if your three phase motor is running in reverse?
yes
Why three phase motor run in reverse even if it is not wired to run in reverse direction?
If a three phase motor in running in reverse, then one of the phases is reversed, plain and simple. If the wiring is correct at the motor, perhaps the phase reversal occurred someplace else.
Can you use single phase kwh meter for three phase load?
No, a single phase kWh meter is designed to measure the energy consumption of single phase loads only. To measure the energy consumption of a three phase load, you would need a three phase kWh meter specifically designed for that purpose. Using a single phase meter for a three phase load would not provide accurate energy consumption readings.
What is the difference between single phase and three phase voltage measurement?
Phasing, or the number of phases in an electrical system has nothing to do with the voltage. A single phase and three phase supply could have a voltage supply of any given voltage from virtually 0 to infinity. Most single phase power supplies in the US are 120/208-240 volt. Three phase power supplies are typically 120/208 to 277/480 volt.
How would a three phase meter reading compare to three single phase meters connected to the same service?
The reading on the 3-ph meter would equal the sum of the three separate readings on the single-phase meters. The neutral sides of the single phase meters do not need to be connected to the neutral wire as long as they are connected together.
To reverse the rotation of a three phase motor you would?
Switch two of the three wires.
How do you connect two single phase watt-hour meters to measure three phase lines?
Two single phase meters are not needed. A three phase meter is manufactured and is used when installing a three phase electrical distribution.
What will happen if we use current transformer of different rating for each phase in three phase supply?
A current transformer has to have the same ratio as the meter that it drives. Full scale deflection on the meter is 5 amps which equals the maximum allowed current on the phase that it is reading. A different ratio on the CT to meter would show an erroneous reading on the meter depending on the ratio of the connected CT. To keep costs down the meter is common to all three phases and is read by connecting the meter to the phase CT through a three position switch.
How do you change rotation on a Century AC motor?
There are two alternate methods depending on whether the motor is single phase or three phase. On a single phase motor, reverse either the start winding coil lead or the run winding coil lead but not both. This action will reverse the motor's rotation. On a three phase motor, interchanging any two of the three coil leads will reverse the motor's rotation.
How does a 3 phase meter handle using on 220 volt single phase and does the meter measure the wattage usage accurately?
A 3-phase meter measures the sum of the power in the three phases, so if power is drawn on one phase only it will still be correctly measured.
How can wire up the voltmeter to measure 3 phase supply without rotary switch?
There are only two ways this can be accomplished. The most economical way to measure three phase voltages is with one meter and a rotary switch, that has an off position, to connect the one meter to each of the three phases one at a time. The other approach is to have three volt meters connected to each phase to measure each phase individually. With the three meter approach you will still need a switch in each meter so that the meter can be taken out of the circuit when no reading is needed.
