An industrial autoclave has a stainless steel outer chamber and two independent electric heating elements.
The total power rating of the autoclave when running at full capacity is 2500 W2500\text{ W}2500 W. It is connected to a standard 230 V230\text{ V}230 V mains electrical supply.
(i) State the equation linking power, current, and voltage.
(ii) Calculate the current drawn by the autoclave. Give your answer to two significant figures.
(iii) Which of these mains fuses is the most suitable for the autoclave?
The two heating elements within the autoclave can be connected either in series or in parallel. Describe one operational advantage of each configuration in this appliance.
Many heavy-duty laboratory appliances are fitted with a three-core cable containing an earth wire.
(i) Describe how an earth wire works in combination with a fuse to protect a user from electric shock.
(ii) Explain why this steel-bodied autoclave must be fitted with an earth wire, whereas a laboratory hotplate with a fully polymer (plastic) outer housing does not require one.
