# 3 phase heater delta connection

Y-Y, Y-Delta, Delta-Y, etc. There exist long, complicated equations for converting between Y and Delta resistor networks, but there is a much simpler solution to this problem than that! Let’s see how this works in an example circuit: (Figure below) The load on the Δ source is wired in a Δ. Let the current in line BB’ be IL.. This is not necessary (or even possible!) In balanced “Y” circuits, the line voltage is equal to phase voltage times the square root of 3, while the line current is equal to phase current. Delta Connection Example Circuit Analysis. In Delta connection, The phase voltage is equal to the line voltage, hence it needs more number of turns which increase the total cost. I1 is the line current in line 1 connected to the common point of R. Similarly, I2 and I3 are the line currents in lines 2 and 3, connected to common points Y and B, respectively. 9.28(a), I1, I2 and I3 by applying KCL at the three terminals R, Y and B, respectively. Create one now. Obviously the total power in the 3 Phase Delta Connection is the sum of the powers in the three phases. In the Delta-Y system, none of the phase voltages will be affected by the failure of the source phase winding. It would depend on the configuration and rating of the controller, the size of wires, UL listings, etc. The phasor addition of these currents is shown in Fig. A Launchpad-Controlled Clapper, Op-Amps as Low-Pass and High-Pass Active Filters, The conductors connected to the three points of a three-phase source or load are called, The three components comprising a three-phase source or load are called. A Star Connection is a 4 – wire system and a Delta Connection is a 3 – wire system. Here’s a hint: if you were to repair the neutral wire and take current measurements with a digital instrument (using a clamp-on current probe, for safety), you would find that the predominant frequency of the current is 180 Hz, rather than 60 Hz. Don't have an AAC account? In balanced Δ circuits, the line voltage is equal to phase voltage, while the line current is equal to phase current times the square root of 3. Due to the phase angles of these three voltage sources, however, this is not the case. With the above circuit, the line voltage is roughly 208 volts. Open source winding of a “Y-Y” system halves the voltage on two loads and loses one load entirely. Certainly, something must be different from before, with one winding completely failed open! With a Δ-connected load, two of the resistances suffer reduced voltage while one remains at the original line voltage, 208. If there are any such transformer configurations located near your campus, it would be an interesting field exercise to bring students there (or send them there on “field research”!) The voltage across open Δ should be zero. With each load resistance receiving 120 volts from its respective phase winding at the source, the current in each phase of this circuit will be 83.33 amps: So each line current in this three-phase power system is equal to 144.34 amps, which is substantially more than the line currents in the Y-connected system we looked at earlier. Therefore, it needs a low number of turns, hence saving in copper. Calculate all voltages, currents, and total power in this balanced Y-Y system: Calculate all voltages, currents, and total power in this balanced Delta-Y system: Calculate all voltages, currents, and total power in this balanced Y-Delta system: What resistor values would we have to choose in a Delta configuration to behave exactly the same as this Y-connected resistor network? The usefulness of this connection scheme should be clearly evident: three different voltage levels may be accessed for use in powering circuits. Star and Delta Connections are the two types of connections in a 3 – phase circuits. Being that pole-mounted power distribution transformers are exposed for anyone to look at, they provide an excellent opportunity for students to practice identifying three-phase connections. 9.28(a), indicate the direction of currents when they are assumed to be positive and not their actual direction at a particular instant. It is possible for one of the windings in a Δ-connected three-phase source to fail open (Figure below) without affecting load voltage or current! Total power is equal to three times the power in each phase. In Fig. 9.30(c). IL = √3 IPh. The above equation is a general equation for the line current n a balanced n-phase mesh system. With each load phase element directly connected across a respective source phase winding, the phase voltage will be constant regardless of open failures in the load elements. ): These transformers are connected in a Y-Delta configuration. One might wonder if we’ve lost all the advantages of three-phase power here, given the fact that we have such greater conductor currents, necessitating thicker, more costly wire. For the circuit shown above, the phase voltage is 120 volts. Starting with the top winding and progressing counter-clockwise, our KVL expression looks something like this: Indeed, if we add these three vector quantities together, they do add up to zero. where Φ is the phase angle between phase voltage and phase current. Perhaps the greatest advantage of the Δ-connected source is its fault tolerance.