Exam Question
(a) Sketch a standby battery charging/discharging circuit. (8)
(b) Describe the circuit sketched, making special reference to how battery charge is maintained and how it operates upon loss of main power. (8)
Class 2 (2nd Engineer)
MET
📅 Oct 2020
Reference Answer
The DC charging supply is obtained from the main busbar. A transformer will step down the voltage to required charging voltage and a rectifier will provide DC voltage at required charging emf
When charging from a discharged state, emf is supplied through a branch ‘A’ at full charging voltage
A voltage monitor ‘V’ monitor the voltage of the cell and gets energised when cell its full charge emf of 2.2V/cell.
‘V’ closes contact V1 and energises contact ‘TC’, then TC 1 gets open and TC2 gets closed and current passes through a resistor for trickle charging.
When charging from a discharged state, emf is supplied through a branch ‘A’ at full charging voltage
A voltage monitor ‘V’ monitor the voltage of the cell and gets energised when cell its full charge emf of 2.2V/cell.
‘V’ closes contact V1 and energises contact ‘TC’, then TC 1 gets open and TC2 gets closed and current passes through a resistor for trickle charging.
Full answer on MeoMock — surveyor-grade reference answers for 7,000+ written exam questions.
Prepare on Android — MeoMock on Google Play