Describe secondary wiring electrical circuits in the secondary side of the current transformer and voltage transformer on the low voltage side. Currents and voltages are derived from current transformers and voltage transformers are used in addition to measurement is also used to operate relays to for purposes of protection. Then close the relay contacts in the direct current circuit from battery to battery PMT and download trip indicator light turn on and sound the alarm.
Figure II.109 illustrates the secondary wiring of a feeder (line out) r elai protected by overcurrent relays and circuit interruption ground.
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Figure II.109 Secondary Wiring of the protected feeder A Overcurrent Relay and Relay Connecting Land Disturbance
Description:
The current transformer; TT = Voltage Transformer; PMT = Breaker Power; OCR = Overcurrent relays; GFR = Relay Land Disturbance; TC = Trip Coil; CC = Closing Coil; MA = Magnetic Alarm; —- = Mechanical linkages; K3 and K9 normally open.
If there is more current noise, then the OCR work and close the relay contacts trip coil TC KI so that working men-trip PMT. If the ground circuit interruption arise where GFR work and close the relay contacts K2. Contact K3 used to download manually PMT trip through the provision of current to the trip coil TC.
Contact K9 PMT is used to enter through the provision of current to the closing coil CC. If the PMT entrance, then the mechanism will close the contacts K4 PMT to allow the trip coil TC work and close contacts K5 to turn on a red light is a signal that the PMT entrance.
If PMT trip, then the state of the contacts due to mechanical relationship with PMT becomes:
」K4 contacts open to stop / break the trip coil current through the trip coil TC so as not to burn.
」Contacts K5 open to turn off the red light.
」Contact K6 closes to turn on the green light is a signal that the PMT is open.
」Contact K7 closes to allow the closing coil contact K9 CC work when pressed.
Contact K8 close to sound the alarm as a sign that the PMT trip. Contact K8 must be reset, meaning that it can be opened mechanically without disturbing other contact position and after a reset to turn off the alarm, its position must be ready to work again when the PMT trip again.
Reset contacts consist of two shafts and shaft drive. I drive shaft is driven by a 2 button while the drive shaft is driven by a magnetic alarm that is connected in series with MA Closing Coil CC. Each drive shaft has to be dragged bulge bulge. A and c bulge bulge dragged by the drive shaft 1. Bulge b and d dragged by a drive shaft protrusion 2.