Question 1
(1)(a) State two advantages of alternator over generator.
(b) List three parts of a generator.
(c) State two means of charging a lead-acid battery.
(d) How many cells are in a 12V battery?
(e) State the Ohm’s Law.
Observation
The candidates that attempted this question did well. However, a few of them could not satisfactorily answer questions 1 (a) and (b). Below are the solutions of the poorly answered questions.
Solution
(a) Advantages Alternator over Generator
- It has lower cost of maintenance.
- It has much higher operating speed due its smaller pulley.
- It gives better power output at both low and high speeds.
- It is lighter in weight.
- It is smaller, hence consumes less space.
- It has simpler control system.
- It has greater reliability.
(b) Parts of Generator
- Armature
- Commutator
- Field coils or pole windings
- Yoke or casing
- Brushes
- Bushes or bearings
- End bracket
- Brush holder or spring
- Spindle end
- End plate
- Through bolts