Quantcast Figure 4-17.Single-phase transformer connected to give 120/240-volt  three-wire  single-phase  service.

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
Figure  4-17.—Single-phase  transformer  connected  to  give 120/240-volt  three-wire  single-phase  service.  Transformer secondary  coils  are  connected  in  series. ungrounded  delta  primary  voltage  system  to  obtain 120/240-volt   single-phase   three-wire   service. Normally the wire connected to the center low-voltage bushing will be connected to ground. Grounding the wire  connecting  to  the  center  bushing  limits  the voltage  aboveground  to  120  volts,  even  though  the wires  connecting  to  the  outside  secondary  bushings have 240 volts between them. Figure 4-18 schematically shows the single-phase distribution transformer connections to a three-phase four-wire wye grounded neutral primary system rated 4,160Y/2,400 volts to obtain 120/240-volt single- phase  secondary  service.  The  three-phase  four-wire wye grounded neutral system has voltage between phases equal to the phase or line to neutral voltage multiplied by 1.73. In figure 4-18, the primary system line to neutral voltage is 2,400 volts, and the voltage between phases is 1.73 times 2,400, or 4,160 volts. This  system  is  designated  as  a system. Other standard three-phase four-wire wye grounded   neutral   primary   system   voltages   are a n d The  transformer  connections  to  obtain  120, 120/240-volt  secondary  service  are  normally  completed inside the tank of the transformer (fig. 4-19). The Figure 4-19.—Shows connections for 120/240-volt three-wire, 240-volt  three-wire,  and  120-volt  two-wire  services. Figure 4-18.—Single-phase transformer connected to provide 120/240-volt three-wire single-phase service. Primary winding is connected to neutral or ground. 4-13



Construction News
 


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +