Maximum demand is defined as:

Maximum demand is the highest load expected after applying diversity factors.

the sum of all connected equipment ratings ignoring diversity

the rated current of the main protective device

the prospective fault current at the origin

the maximum expected load taking diversity into account

In a domestic ring final circuit, socket-outlets are assumed to share the load because:

Ring circuits use diversity assumptions, as not all sockets operate at the full 13 A simultaneously.

based on diversity, often well below the full 13 A per socket

taken as the full 13 A at every socket, all assumed to be in use at once

fixed at 32 A, whatever number of sockets is fitted on the ring

equal to the current-carrying capacity of the circuit cable, taken at each outlet

A diversity factor is normally expressed as:

A diversity factor is typically less than 1 (or less than 100%), as not all loads operate at full capacity simultaneously.

a whole number greater than the connected load (in kW)

a decimal or percentage less than 1 (or 100%)

a value always equal to exactly 1 (or 100%)

a negative correction (in volts) applied to the supply voltage

Free mock exam

Load Calculations — Level 3 Systems Design Practice

Free topic-focused mock exam: 30 random questions from a pool of 48 on Load Calculations, drawn from the wider Level 3 Systems Design bank. 35-minute timer, 70% to pass, worked explanation on every question. Use this when you've taken the full mock once and want to drill the topics you got wrong.

Questions: 30
Time limit: 35 min
Pass mark: 70% · 21/30
Question bank: 48

Free, no sign-up. Retake as many times as you like — different questions each time.

Sample questions

01Maximum demand is defined as:
- Athe sum of all connected equipment ratings ignoring diversity
- Bthe rated current of the main protective device
- Cthe maximum expected load taking diversity into account
- Dthe prospective fault current at the origin
Why: Maximum demand is the highest load expected after applying diversity factors.
02In a domestic ring final circuit, socket-outlets are assumed to share the load because:
- Aequal to the current-carrying capacity of the circuit cable, taken at each outlet
- Bbased on diversity, often well below the full 13 A per socket
- Cfixed at 32 A, whatever number of sockets is fitted on the ring
- Dtaken as the full 13 A at every socket, all assumed to be in use at once
Why: Ring circuits use diversity assumptions, as not all sockets operate at the full 13 A simultaneously.
03A diversity factor is normally expressed as:
- Aa whole number greater than the connected load (in kW)
- Ba decimal or percentage less than 1 (or 100%)
- Ca negative correction (in volts) applied to the supply voltage
- Da value always equal to exactly 1 (or 100%)
Why: A diversity factor is typically less than 1 (or less than 100%), as not all loads operate at full capacity simultaneously.

Common questions

Is the Load Calculations mock exam free?

Yes — 100% free, no sign-up needed. Questions are pulled at random from a substantial bank, with a worked explanation on every question after you submit.

Can I retake the mock exam?

Yes. Every attempt picks a different random selection and reshuffles the options, so each retake gives you genuinely new questions. No limit on retakes.

Does this count towards the real qualification?

No — this is independent practice material. To gain the actual qualification you need to sit the official assessment through an approved provider.