Assumption University Thailand EE4503 Electrical Systems Design Main Circuit 1

Assumption University Thailand Topics Service conductor Service equipment Service conductor & equipment (LV) Earth fault protection Service conductor & equipment (HV) 2

Assumption University Thailand Main Circuit 3 Main circuit is the part of the circuits connecting between end-user system and the service provider. Service Conductors Service Equipment Highly depends on the local regulation.

Assumption University Thailand Service Conductor 4 By installation –Overhead Service Conductors –Underground Service Conductors By voltage –Low Voltage Service Conductors –High Voltage Service Conductors

Assumption University Thailand Overhead Service Conductors 5

Assumption University Thailand Underground Service Conductors 6

Assumption University Thailand Service Equipment 7 Disconnecting Means –Load Break Switch or Switch Disconnector –Isolating Switch or Disconnector Overcurrent Protection Equipment –Fuse or Circuit Breaker Circuit Breaker is both function ** Check Local Regulation **

Assumption University Thailand Service Equipment Overcurrent Protection 8 Near disconnector Large scale system (from 1,000A) requires Ground Fault Protection

Assumption University Thailand Service Equipment Energy Meter 9 Low Voltage –5(15), 15(45), 30(100), 50(150), 200, 400 –There is requirement or minimum rating of conductor and equipment

Assumption University Thailand Electrical Systems Design: ประสิทธิ์ พิทยพัฒน์ Reference 10