What is a 240 volt 3 phase 3 wire grounded b phase system?
A 240 volt 3 phase 3 wire grounded B phase system is also called a quadraplex configuration. You actually have four conductors, not counting the protective earth ground, which makes five wires. Three conductors are the individual phase hots, A, B, and C. You can use them delta only, and you will have 240 volt three phase. The fourth conductor is neutral, and is connected to the center tap of one of the transformers, and also grounded at the distribution point. You then have 120/240 volt split phase with that neutral and the two hots surrounding it, which is the normal residential configuration for the US. You cannot connect a three phase load in wye configuration, because the neutral is not in the center of the power triangle. If you want a wye configuration, you will need three more transformers, with the primaries delta and the secondaries wye.
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In a three-phase, star- (or wye-) connected, system the linevoltage (line-to-line voltage) is 1.732 (or the square-root of 3)times the phase voltage (line-to-neutral voltage).… The reason forthis is that a line voltage is the vectorial sum (not algebraicsum) of two phase voltages displaced from each other at 60 degrees. These days, incidentally, the UK's nominal phase voltage is230 V, and its corresponding line voltage is 400 V.
Answer for USA, Canada and countries running a 60 Hz power supply service. . It doesn't need to be converted. The 240 Volt single-phase electricity is there already to oper…ate any single phase devices. New breakers, the right size of wiring and a new wall outlet are what have to be installed to add a new single phase 240 Volt circuit to an existing breaker panel which already has a three-phase supply. For safety reasons only a trained and licensed electrician should work with this equipment.. . Careful! The statement above can be misleading. The Asker is obviously not from the US, he thinks US 240V is three phase, when its really single-phase. But note that he wants to convert to single-phase with one hot and one neutral . This is consistent with European standards with 230V single-phase where one wire is hot and one wire is cold (neutral). You cannot connect a European 230V appliance directly to US 240V because this would connect a hot wire to the appliance's grounded connection, potentially making the chassis components hot!. So, while it is true nothing needs to be done to convert US 240V service to single-phase (because it already is), it is not correct to imply that US 240V can be used where you want 240 volts with one hot and one neutral. This would require an isolation transformer or other approved international voltage converter.. For more information see the answer to the Related Question Can you plug a 230V 50Hz appliance into a 240V 60Hz outlet? shown below. . As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed. . If you do this work yourself, always turn off the power at the breaker box/fuse panel BEFORE you attempt to do any work AND always use an electrician's test meter having metal-tipped probes (not a simple proximity voltage indicator) to insure the circuit is, in fact, de-energized. . IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB SAFELY AND COMPETENTLY REFER THIS WORK TO QUALIFIED PROFESSIONALS. .
How do you fuse dry type transformers for an open delta system used to transform 480 Volt 3 phase to 120-240 Volt 3 phase 4 wire?
one transformer is sized for 57.7% of the three phase load, the other carries 57.7 % of the three phase load plus all of the single phase load. find out the kva of your load…s then size your transformers find the rated FLA of the transformers on the primary and secondary with Watt's law add the individual currents with vectors to find the phase currents primary and secondary then apply NEC 430.3(B) Wire is sized to carry the load and be protected by OCPD make sure the wire is protected via 240.21 (B) or (C) tap rules. There are too many possible combinations of primary/secondary protection and tap rules to give a complete answer, your solution will vary based on distance between overcurrent devices and the transformers and also with your choices in regards to transformer KVA sizing. A simpler solution that is lighter, off the shelf, simpler to install and probably cheaper is to use a single three phase transformer with a 240 wye/delta connection. I think that would also gain you some noise isolation.
your equipment will not run as hot (motors & drives will stay cool) . the higher the voltage the less the amps . so when running circuits to equipment you will be able to ru…n smaller conductors, smaller pipe. It's cheaper . To install high power equipment it is not always feasible to increase the current rating of the equipment. . for a 3 phase system power P = 1.732VI. where V stands for voltage and I stands for current. . Increasing voltage instead of current is more feasible for achieving higher power in most of the cases.
480 volts 3 phase is not a household service in any country and cannot be dealt-with as a DIY project. As always, if you are in doubt about what to do, the best advice …anyone should give you is to call a licensed electrician to advise what work is needed. Before you do any work yourself, on electrical circuits, equipment or appliances, always use a test meter to ensure the circuit is, in fact, de-energized. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB SAFELY AND COMPETENTLY REFER THIS WORK TO QUALIFIED PROFESSIONALS. Answer You cannot obtain 240 V from a 480-V three-phase supply, if you are describing a three-phase, four-wire, system. If 240 V is a phase voltage, then the corresponding line voltage must be 415 V. If 480 V is a line voltage, then the corresponding phase voltage must be 277 V.
The voltage rating of a fuse has to do with how long the fuse is / how much dielectric strength exists between the two terminals that don't melt. If you use a fuse that is rat…ed for too low of a voltage, it will likely melt for a fault condition, but the voltage is too high for the gap distance, so an arc will develop across the (open) fuse. So...the fuse does no good. It will not protect equipment if used at a higher voltage than it is rated.
The color code for 3phase 240 volts is PHASE A- BLACK PHASE B- RED PHASE C- BLUE
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240 volt three phase comes from primary distribution main line, usually 13.2 KV three phase, but different for different regions and countries, stepped down with transformers.… There are several possible configurations... You can use three 13.2 KV to 240 V transformers wired in wye-wye, providing 240 phase to neutral and 277 phase to phase. You can use three 13.2 KV to 240 V transformers wired in wye-delta, providing 240 phase to phase. This is an older configuration, saving the fourth transformer. Sometimes, one of the phases is centertapped, providing 120/240 split phase, and the neutral is off-center. In this case, the high side is 208 - opposite phase to neutral. In light industrial loads, you can actually use just two transformers to get the three phases, but total power will be imbalanced. More commonly, in large industrial loads, you can use three 13.2 KV to 480 V transformers wired in wye-wye, providing 480 phase to neutral, and you use more transformers to get down to 240. In even bigger industrial loads, you can use three 13.2 KV to 4160 V transformers into a switchgear room, providing secondary and tertiary transformers for whatever you want.
Yes, most equipment is rated 208-220-240 volts.
The wire size and the circuit breaker for a 125 hp motor must consider the length of lead wire to the motor (essentially the distance of the motor from the supply). 125 hp …is a VERY large motor and would be used only in industrial applications. You will need to consult a technician for proper advice, but the general answer to your question follows: The current draw on such a large motor would be approximately 300 amps. That is very large, and would require a wire size of 0000 AWG or 750M. 0000 AWG is 0.46 inches (11.68 mm) in diameter. As you can see, the wire is very large. It is not something you could install yourself.
Can you change the wiring of a single phase appliance of 2.4 kw that works on 240 to 400 volts 3 phase 60 hz supply?
No, you can not you change the wiring of a single phase appliance of 2.4 kw that works on 240 to 400 volts 3 phase 60 Hz supply. They are two different electrical systems.
How you can produce 240 volts from a single phase 3 wire system with a nominal voltage of 120 volts?
you can use two hot wire different phases with a double pole braker .
Wire sizing is based on the amperage needed by the load. The equation used to find amperage when the HP is shown is; A = HP x 746/1.73 x V x %eff x pf. Amps = 25 x 746 = 18650…/1.73 x 240 x .87 x .87 = 18650/314 = 60 amps. A standard motor's efficiency between 5 to 100 HP is .84 to .91. A standard motor's power factor between 10 to 100 HP is .86 to .92. Motor feeders have to be rated at 125% of the motors full load amperage. 60 x 125% = 75 amps. A #4 copper conductor with an insulation rating of 75 or 90 degrees C are both rated at 85 amps. The breaker has to be 250% of the motors full load amperage 60 x 250% = 150 amps The breaker will be a three pole 150 amp breaker connected to three #4 copper conductors to operate a 25 HP 240 volt three phase motor.
Wire size and breaker size is based on the amperage drawn by the motor. Always use the motor's nameplate amperage before using the equation. The equation for amperage when t…he HP is known is Amps = HP x 746/1.73 x volts x % eff x pf. A standard motor's efficiency between 5 to 100 HP is .84 to .91. A standard motor's power factor between 10 to 100 HP is .86 to .92. Amps = 100 x 746 = 74600/ 1.73 x 240 x .91 x .92 = 74600/348 = 214 amps. Feeders for motor loads has to be rated at 125% of the motors full load amps. The wire rating will be 214 x 125% = 267 amps. A 250 MCM copper conductor with an insulation factor of 90 degrees C is rated at 290 amps. For conductor protection of the motor feeders, non time delay fuses 600 amp, time delay fuses 350 amps and a breaker has to be rated at 250% of the motors full load amps. The nearest breaker for this amperage will be a 500 amp breaker. As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed. Before you do any work yourself, on electrical circuits, equipment or appliances always use a test meter to ensure the circuit is, in fact, de-energized. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB SAFELY AND COMPETENTLY REFER THIS WORK TO QUALIFIED PROFESSIONALS.
What voltage would be produced if two different 240 volt transformers were wired on two separate primary phases of a 3-phase system and had their their secondaries wired in series?
In U. S. household wiring the two primary phases of 110 to 120volts rms are 180Â° out of phase with each other which is why thevoltage measured from line 1 to line 2 is doub…le that of each linemeasured to the common return. The outputs of two identicaltransformers would therefore be additive if connected in series andin phase and subtractive if out of phase. Please note that if thephase relationship of the inputs is unknown, such as that comingfrom two independent portable generators, for example, the summedoutput voltage will be unpredictable.