In Europe, low-voltage three-phase distribution is by means of a four-wire system (three line conductors and a neutral) supplied from a wye-connected transformer secondary.
In North America, low-voltage is supplied from a delta-connected transformer secondary, one phase of which is centre-tapped and earthed (grounded). The single-phase supply to residences is then supplied by that particular phase, giving 240 V line-to-line and 120 V line-to-neutral.
You can tell if you have a delta power when the phase voltage is equal to the line voltage and that you have a star power when the phase voltage =root 3(THE LINE VOLTAGE).
For the same load, delta provides higher current than wye, or star.Wye voltage is 1 / 1.732, or 0.577 that of delta. (1.732 is the square root of 3.) This gives a power of 0.333 for wye, as opposed to delta. (0.5772 = 0.333)This is why (no pun intended) we use wye-delta starters on large motors - it allows them to come up to speed at 1/3 power, before switching to full power on delta.
It is not true that another name for the "Y" or "wye-connected" system of polyphase power is the "delta" system. It's called the "star" system.
To terminate a 3 wire wye motor to a 3 phase delta connection you need a 3 phase transformer to convert from delta to wye. Do not lift the common neutral connections inside the motor and rewire for delta, because the voltages will be wrong.
In a three phase transformer, the primary winding is often configured in a Delta. The delta winding configuration does not use a neutral. The secondary winding is often in a Wye configuration, which does have a neutral. The Delta configuration is typically used for transmitting power to various locations, and thee phase loads where a neutral is not needed. The Wye configuration is typically used to distribute power in a facility where there are single phase loads that need a neutral. There are other reasons to use either Wye or Delta, such as grounding issues, but I think the short answer is probably what you're looking for (I hope). Hope this helps! Dave
It is a type of starter that allows a motor to be started across the line by starting the motor with a reduced inrush current. The motor is started in a wye configuration until it gets up to speed and then a timer drops the wye contactor out a draws the delta configured contactor in. The motor then operates in a delta wired configuration.
For the same load, delta provides higher current than wye, or star.Wye voltage is 1 / 1.732, or 0.577 that of delta. (1.732 is the square root of 3.) This gives a power of 0.333 for wye, as opposed to delta. (0.5772 = 0.333)This is why (no pun intended) we use wye-delta starters on large motors - it allows them to come up to speed at 1/3 power, before switching to full power on delta.
It is not true that another name for the "Y" or "wye-connected" system of polyphase power is the "delta" system. It's called the "star" system.
A star-delta motor should be supplied star-delta.Wye is simply another name for star. Star-delta motors use a star or wye configuration to start, and a delta configuration to run. This reduces the voltage on the windings during the high current starting time.
10 hp and above motor power rating....
The power of a three-phase load is the sum of the three individual loads. It makes no difference whether they are connected in star (wye) or in delta.
To terminate a 3 wire wye motor to a 3 phase delta connection you need a 3 phase transformer to convert from delta to wye. Do not lift the common neutral connections inside the motor and rewire for delta, because the voltages will be wrong.
Whether a transformer is 'step up' or 'step down' has nothing to do with the way its windings are connected, so it could be wye-delta or delta-wye.
in low voltage connection in wye (star conncetion) 415v high voltage connection in delta 480v
In a three phase transformer, the primary winding is often configured in a Delta. The delta winding configuration does not use a neutral. The secondary winding is often in a Wye configuration, which does have a neutral. The Delta configuration is typically used for transmitting power to various locations, and thee phase loads where a neutral is not needed. The Wye configuration is typically used to distribute power in a facility where there are single phase loads that need a neutral. There are other reasons to use either Wye or Delta, such as grounding issues, but I think the short answer is probably what you're looking for (I hope). Hope this helps! Dave
It is a type of starter that allows a motor to be started across the line by starting the motor with a reduced inrush current. The motor is started in a wye configuration until it gets up to speed and then a timer drops the wye contactor out a draws the delta configured contactor in. The motor then operates in a delta wired configuration.
first you need to touch yourself
An open delta connection is a delta connection with one phase removed, but still supplied with three line conductors. An open wye is a wye connection with one phase removed, supplying a three line conductors and a neutral conductor. An open-delta/open-wye is a method of providing a reduced-load three-phase supply using just two single-phase transformers, rather than the preferred method of using three single-phase transformers.