CPD · Engineering

Checking a protection setting

Reviewing a protection setting against the fault level and the load.

about this course

What you will be able to do

L5 SpecialistAbout 4 hours (240 minutes) of CPDSelf-study plus role-playEngineering

Reviewing a protection setting against the fault level and the load.

Interpret a time-current curve, given a sample, identifying pick-up and time for two faults.
Check a setting, given a fault level and load, that it trips for faults and not for normal load.
Identify a coordination problem, given two curves, with the point of overlap named.
Record the finding, given a template, with a clear pass or fail.

Task, condition and standard

Task

Read a one-line diagram and coordination curves, check a protection setting against the fault level and load, and report any mismatch with a clear pass or fail

Condition

Given a sample one-line diagram, two time-current curves, a fault level and load, and a report template, in a 4-hour practical session

Standard

Name every device from supply to motor, identify pick-up and trip time on two curves, show where a downstream device does or does not trip first, and report a mismatch with setting, expected value, difference and location

These courses teach process, communication and recording. They give no clinical, legal, tax, financial or engineering sign-off. A named subject expert must review every line, and you must check your own professional body's current CPD rules, before you rely on a certificate.

sessions

8 modules

Module 1 One-line diagram basics 30 min

A one-line diagram shows the path of power in single lines.
Each symbol is one device with one job.
Read from the supply to the motor.

Worked example. Sample diagram: 400 V supply, main breaker 400 A, feeder breaker 100 A, motor starter, 37 kW motor. Four items named from the supply down to the motor starter, with the 37 kW motor as the load, each with its purpose: supply (source), main breaker (isolate and protect the board), feeder breaker (protect the feeder), motor starter (start and protect the motor).

Practise: Practise with a case card or template for "one-line diagram basics": interpret a time-current curve, given a sample, identifying pick-up and time for two faults.

Standard to meet. Read a one-line diagram and name each device from supply to motor, stating the purpose of every device shown on the diagram.

Module 2 Device order from source to load 30 min

List devices from source to load.
For a fault at the load, the device nearest the load should act first.
That order is called selectivity.

Worked example. Order for a motor fault: main 400 A, then feeder 100 A, then motor starter. Expected first to act: the motor starter. The feeder is the backup and the main is the last resort.

Practise: Practise with a case card or template for "device order from source to load": check a setting, given a fault level and load, that it trips for faults and not for normal load.

Standard to meet. List the devices in order from source to load, given a one-line diagram, and state which device should act first for a fault at the load.

Module 3 Coordination curves 45 min

Pick-up is the current at which a device starts to act.
Trip time is read on the curve at the fault current.
Two curves must not cross where faults can occur.

Worked example. On the sample curves, at a 1,000 A fault: feeder (pick-up 100 A) trips in 0.10 s; main (pick-up 400 A) trips in 0.40 s. The 0.30 s gap means the downstream feeder acts first, so the curves do not cross there.

Practise: Practise with a case card or template for "coordination curves": identify a coordination problem, given two curves, with the point of overlap named.

Standard to meet. Interpret two coordination curves, given a sample, identifying pick-up and time for a fault and showing where the downstream device does or does not trip first.

Module 4 Checking a setting 35 min

A setting must not trip on normal load.
It must trip on the fault level given.
Compare the setting with both numbers.

Worked example. Sample values: normal load 80 A, fault level 3,000 A. Setting: pick-up 100 A, fast trip at 1,000 A. 80 A is under 100 A, so no trip on load. 3,000 A is over 1,000 A, so it trips fast. Result: pass.

Practise: Take the end check for "checking a protection setting": show that you can record the finding, given a template, with a clear pass or fail, and meet every outcome standard above.

Standard to meet. Check a given setting against the coordination curve, given a fault level and load, and state whether it trips for faults but not for normal load.

Module 5 Reporting a mismatch and next check 25 min

Name the device, the setting and the location.
Give the expected value, the actual value and the difference.
Say the next check and who owns it.

Worked example. Sample report: feeder F2 at panel P1, trip time 0.45 s at 1,500 A, expected 0.10 s, difference 0.35 s. Next check: ask the responsible engineer to review the setting. Do not change it yourself.

Practise: Practise with a case card or template for "reporting a mismatch and next check": record the finding, given a template, with a clear pass or fail. Use a new case this time (round 2).

Standard to meet. Report a mismatch, given two curves that cross, naming the setting, expected value, difference and location, and state the next check for the responsible engineer.

Module 6 Assessment 15 min

Give a clear pass or fail with evidence.
Say plainly what you could not verify.
Do not guess a missing value.

Worked example. Sample case: fault 1,500 A, feeder trips in 0.08 s, main in 0.35 s. Pass, with the curve readings as evidence. The motor starter curve was not supplied, so it is reported as not verified.

Practise: Practise with a case card or template for "assessment": record the finding, given a template, with a clear pass or fail. Use a new case this time (round 2).

Standard to meet. Check a sample case, given curves and a one-line diagram, with a clear pass or fail and evidence, and say plainly when something cannot be verified.

Module 7 Second worked case: crossed curves 30 min

Mark both curves at the same fault current.
The downstream device must be faster, not slower.
State the mismatch and the next step.

Worked example. Case card 2: at a 2,000 A fault the downstream feeder trips in 0.50 s and the upstream main in 0.30 s. The feeder is 0.20 s slower, so the main trips first. Report the mismatch and ask the responsible engineer.

Practise: Practise with a case card or template for "second worked case: crossed curves": record the finding, given a template, with a clear pass or fail. Use a new case this time (round 2).

Standard to meet. Identify two crossing curves at a given fault current, state the time difference, and report the mismatch with the next step for the responsible engineer.

Module 8 Teach-back and peer check 30 min

Explain your reading to a partner in plain words.
The partner checks three things: order, trip times and wording.
Swap roles and agree one improvement each.

Worked example. Pairs of 2: reader 3 minutes, partner checks the device order, two trip times and the report wording. Target: 4 of 4 devices named in order and both trip times read within 0.05 s.

Practise: Practise with a case card or template for "teach-back and peer check": record the finding, given a template, with a clear pass or fail. Use a new case this time (round 2).

Standard to meet. Evaluate a partner's curve reading and mismatch report against a checklist, give one strength and one improvement, and confirm the device order and trip times are correct.

practice

Worked example and case cards

Worked example

One-line: supply, main breaker, feeder breaker, motor. Rule of thumb for order: devices nearer the load must trip faster than devices nearer the supply for the same fault (selectivity). Compare the given settings with the coordination curve; if the feeder curve crosses above the main's, report the mismatch and ask the responsible engineer.

Case card

two curves and a one-line diagram.

Case card 2

A downstream breaker trips later than the upstream. Learners mark the curves, state the mismatch and next step.

checks

10 check questions with model answers

What is selectivity?

Model answer: Only the device nearest the fault trips. (Covered in module 2: Device order from source to load. To pass that module: List the devices in order from source to load, given a one-line diagram, and state which device should act first for a fault at the load.)

Who changes a setting?

Model answer: Only the authorised person. (Covered in module 5: Reporting a mismatch and next check. To pass that module: Report a mismatch, given two curves that cross, naming the setting, expected value, difference and location, and state the next check for the responsible engineer.)

What do you report?

Model answer: The device, the setting, the mismatch, the evidence. (Covered in module 5: Reporting a mismatch and next check. To pass that module: Report a mismatch, given two curves that cross, naming the setting, expected value, difference and location, and state the next check for the responsible engineer.)

Is a pass on paper enough?

Model answer: No; say what could not be verified and ask a qualified person to confirm on site. (Covered in module 6: Assessment. To pass that module: Check a sample case, given curves and a one-line diagram, with a clear pass or fail and evidence, and say plainly when something cannot be verified.)

What is coordination?

Model answer: Only the device nearest the fault trips. (Covered in module 3: Coordination curves. To pass that module: Interpret two coordination curves, given a sample, identifying pick-up and time for a fault and showing where the downstream device does or does not trip first.)

Who may change a setting?

Model answer: Only an authorised person, with a change record. (Covered in module 5: Reporting a mismatch and next check. To pass that module: Report a mismatch, given two curves that cross, naming the setting, expected value, difference and location, and state the next check for the responsible engineer.)

What do you report?

Model answer: Setting, expected value, difference, location. (Covered in module 5: Reporting a mismatch and next check. To pass that module: Report a mismatch, given two curves that cross, naming the setting, expected value, difference and location, and state the next check for the responsible engineer.)

Why list devices in order?

Model answer: To trace which one should act first. (Covered in module 2: Device order from source to load. To pass that module: List the devices in order from source to load, given a one-line diagram, and state which device should act first for a fault at the load.)

What if you cannot verify?

Model answer: Say so; do not guess. (Covered in module 6: Assessment. To pass that module: Check a sample case, given curves and a one-line diagram, with a clear pass or fail and evidence, and say plainly when something cannot be verified.)

At a 2,000 A fault the feeder trips in 0.50 s and the main in 0.30 s. What is the gap and what do you report?

Model answer: The downstream feeder is 0.20 s slower, the wrong way round; report the device, setting, difference and location, and ask the responsible engineer. (Covered in module 7: Second worked case: crossed curves. To pass that module: Identify two crossing curves at a given fault current, state the time difference, and report the mismatch with the next step for the responsible engineer.)

glossary

Words used in this course

one-line diagram, coordination, trip curve, setting, change record.

marking

How the practice and assessment are marked

Level	Meaning	Marks of 4
Secure	Meets the standard in the outcome every time, no prompts	4
Meeting	Meets the standard with one small slip, corrected when prompted	3
Developing	Meets part of the standard; needs a re-attempt	2
Not yet	Standard not met	1

Pass = average 3 or more, and no outcome at 1. You may re-attempt after feedback. The subject expert sets any stricter pass mark.

where next

Ladder L1 to L7, slide by slide with notes

Slide 1: L1 Basic: What protection does. Speaker note: A protective device cuts off power when a fault occurs. At this first step the learner can say why a fault is dangerous and why a breaker must open fast enough to protect people and equipment.
Slide 2: L2 Awareness: Reading a one-line diagram. Speaker note: The learner can follow a one-line diagram from the supply to a motor and name each device and its purpose. They know that only an authorised person may change a setting, with a change record.
Slide 3: L3 Foundation: Order and curves. Speaker note: The learner knows the device order from source to load and can find pick-up and trip time on a simple curve with help. They follow the worked example where the feeder must act before the main.
Slide 4: L4 Practitioner: Check a setting and report. Speaker note: This course sits here. The learner checks a setting against fault level and normal load, spots where two curves cross, and reports a mismatch with a clear pass or fail and the evidence.
Slide 5: L5 Specialist: Several devices in a chain. Speaker note: The specialist checks chains of three or more devices, with motor starting current and different fault levels along the line. They find the weakest gap and propose what the responsible engineer should review.
Slide 6: L6 Advanced: Review and verify on site. Speaker note: The advanced practitioner reviews other people's findings, asks for site tests that confirm a paper pass, and records what could not be verified rather than guessing. They keep change records complete.
Slide 7: L7 Super expert: Set the checking standard. Speaker note: The super expert writes the checking method and report template for a team. They audit past findings for missed mismatches, train others in selectivity, and advise on when a study needs a specialist.

This course sits at L5 Specialist. Credits stack; aligned with, not accredited by, any framework.

jobs this leads to

Where this takes you

Electrical technician
Protection technician
Commissioning assistant
Junior electrical engineer
Maintenance electrician

assessment and certificate

How you are checked

Each outcome is checked against its standard with a checklist or a short test. A digital CPD record shows the hours. Keep evidence in My page. Aligned with common CPD practice; not accredited. Learners check their own body's rules.

ten locations and global

Your place

Use your own body's forms, units and currency. Local professional bodies set the rules for CPD hours; check them first.

India (Bengaluru)

Language: English, Hindi, Kannada. Personal data: Digital Personal Data Protection Act 2023. Credit and levels: National Skills Qualifications Framework (NSQF) and the national credit framework.

Netherlands (Eindhoven area)

Language: Dutch, English. Personal data: EU GDPR (Dutch: AVG), supervised by the Autoriteit Persoonsgegevens. Credit and levels: the Dutch qualification framework (NLQF) linked to the European Qualifications Framework.

UAE (Dubai and Abu Dhabi)

Language: Arabic, English. Personal data: Federal Decree-Law No. 45 of 2021 (personal data protection). Credit and levels: the emirate education and training regulators (for example KHDA in Dubai) and the national qualifications framework.

Brazil (Sao Paulo)

Language: Portuguese (Spanish and English support). Personal data: LGPD (Lei Geral de Protecao de Dados). Credit and levels: the national technical-education catalogue and the national S-system training bodies.

Canada (Toronto)

Language: English, French. Personal data: PIPEDA, with provincial rules where they apply. Credit and levels: the provincial colleges framework and the national credential-recognition guidance.

United States

Language: English, Spanish. Personal data: state privacy laws (for example California), and COPPA for children under 13. Credit and levels: state and community-college credit systems.

Singapore

Language: English, Mandarin, Malay, Tamil. Personal data: Personal Data Protection Act (PDPA). Credit and levels: the Singapore national skills frameworks and the national credit system.

Australia

Language: English. Personal data: the Privacy Act 1988 and the Australian Privacy Principles. Credit and levels: the Australian Qualifications Framework (AQF) levels.

Hong Kong (Eastern Asia)

Language: Chinese (Cantonese, Mandarin), English. Personal data: the Personal Data (Privacy) Ordinance. Credit and levels: the Hong Kong Qualifications Framework.

Georgia and Israel (Western Asia)

Language: Georgian, Hebrew, Arabic, English. Personal data: the personal data law of the country where the learner lives. Credit and levels: the national qualifications framework of that country.

Cayman Islands (Caribbean)

Language: English. Personal data: the Data Protection Act. Credit and levels: the local education and training framework.

Mexico

Language: Spanish, English. Personal data: the federal law on personal data held by private parties. Credit and levels: the national competency certification system and the education ministry levels.

Draft

Draft CPD course. It opens only after final checks. No fee is shown.

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