An electric submersible water pump, Pump X, is used in a garden pond filter system. It is powered by an electric motor.
Pump X is designed to operate on the mains supply and is labelled 230 V230\text{ V}230 V, 115 W115\text{ W}115 W.
What does 115 W tell you about how energy is transferred in the pump?
Pump X has a metal outer casing and an earth connection. Explain how the earth connection protects the user.
Pump Y is a low-voltage submersible pump connected to a step-down power supply. It is labelled 24 V24\text{ V}24 V, 110 W110\text{ W}110 W.
A student says: "I think that both pumps should be fitted with a 5 A5\text{ A}5 A fuse."
Use calculations to evaluate this statement.
There is a step-down transformer in the power supply for Pump Y. Describe the structure of a step-down transformer.
