Startup and commissioning are where design, installation and real operating conditions finally meet.

On paper, the electrical system may look complete.

In the field, the system may still have loose terminations, incorrect phasing, insulation damage, missing bonds, misconfigured protection, control wiring errors, damaged equipment, wrong labels or software settings left in default mode.

That is the point of commissioning.

It is not only there to confirm that everything is perfect. It is there to find problems before they become failures.

The original JM Test article makes this point clearly: commissioning is the stage where equipment is energized for the first time, installation quality is tested, and issues that may not be visible during normal inspection can be found before they cause downtime, safety hazards or equipment damage.

For Canadian electrical contractors, engineers, facility owners and maintenance teams, commissioning should be tied to the project specification, manufacturer instructions, CSA C22.1 Canadian Electrical Code requirements where applicable, CSA Z462-informed electrical safety practices, the authority having jurisdiction and the owner’s commissioning plan.

Why Electrical Failures Are Common During Commissioning

Electrical systems are complex.

A single project may include:

• Switchgear
• Transformers
• Motor control centres
• Distribution panels
• Breakers
• Relays
• Fuses
• Cables
• Bus connections
• Grounding and bonding systems
• Motors
• Drives
• Controls
• PLCs
• SCADA points
• Instrumentation
• Metering
• Alarms
• Communications
• Standby power systems
• UPS systems
• Battery systems
• Energy storage systems
• Building systems
• Labelling and documentation

Even when installation is generally well managed, small issues can remain hidden until the equipment is tested, energized or placed under load.

The source JM Test article explains that commissioning testing exists because visual inspection alone cannot verify performance, and that small oversights can become significant problems once voltage and load are applied.

A good commissioning process catches those issues while the project team is still in a controlled correction phase.

Loose or Improper Electrical Connections

Loose electrical connections are one of the most common startup findings.

They can occur at:

• Terminals
• Lugs
• Bus joints
• Grounding points
• Breaker connections
• Transformer connections
• Motor terminals
• Control terminals
• Panelboards
• Switchgear
• Motor control centres
• Junction boxes
• Cable terminations

A loose connection can create higher resistance.

Higher resistance can create heat.

That heat can make the connection worse over time through thermal cycling, oxidation, loosening and material damage.

The source article notes that even slightly under-torqued connections can generate excessive heat once current flows, and that commissioning tests such as torque verification, contact resistance testing and thermal inspection often reveal these issues before permanent damage occurs.

Common ways to find connection problems include:

• Visual inspection
• Torque verification where specified
• Contact resistance testing
• Low-resistance ohmmeter testing
• Thermography under load
• Load testing
• Functional testing
• Review of installation records

For Canadian work, torque values should come from the manufacturer, project specifications, engineered procedures or approved installation documents. Do not guess torque values based on lug size alone.

Incorrect Phase Rotation and Phasing Errors

Phase rotation errors are common during new installation, retrofit and modification work.

They can happen when conductors are misidentified, terminated incorrectly, labelled incorrectly or changed during field work.

Incorrect phasing can cause:

• Motors to run backward
• Pumps to operate in the wrong direction
• Fans to spin the wrong way
• Compressors to fail
• Drives to fault
• Transfer systems to malfunction
• Parallel systems to be unsafe
• Protection and metering problems
• Unnecessary troubleshooting delays

The original article explains that phase rotation errors can cause motors to run backward, damage equipment or disrupt coordinated system operation, and that phase rotation testing during commissioning confirms systems are wired correctly before they are placed under load.

Commissioning checks may include:

• Phase rotation testing
• Voltage checks
• Phasing checks
• Motor bump tests
• Control sequence testing
• Transfer switch testing
• Synchronization checks where applicable
• Verification against drawings and labels

For motors, always confirm that the driven equipment can be safely bumped before a rotation check. Some pumps, compressors, fans and process equipment can be damaged if run in the wrong direction, even briefly.

Insulation Resistance Failures

Insulation resistance testing is a major commissioning tool.

It helps identify insulation problems in cables, motors, transformers, switchgear and other electrical equipment before the system is energized for service.

Insulation issues may come from:

• Moisture ingress
• Damaged cable jackets
• Poor storage
• Installation damage
• Cable pulling damage
• Contamination
• Dust
• Conductive debris
• Manufacturing defects
• Termination damage
• Incorrect handling
• Ageing equipment
• Wrong environmental conditions
• Poor sealing or glands

The source JM Test article notes that insulation resistance testing frequently identifies startup problems in cables and windings, especially where moisture, physical damage or contamination has compromised insulation integrity.

Insulation resistance failures can increase the risk of:

• Ground faults
• Short circuits
• Equipment trips
• Arc flash events
• Motor failure
• Cable failure
• Transformer damage
• Startup delays
• Rework before energization

Commissioning insulation testing also creates a baseline. That baseline can be useful later when maintenance teams compare future test results.

Grounding and Bonding Deficiencies

Grounding and bonding problems are often found during commissioning.

They may include:

• Missing bonds
• Loose bonding conductors
• High-resistance grounding connections
• Incorrect grounding paths
• Poor grounding electrode connections
• Wrong conductor size
• Disconnected equipment grounds
• Missing jumpers
• Poor continuity across doors, frames or enclosures
• Incorrect grounding of separately derived systems
• Grounding not matching the design
• Bonding missing after field changes

The source article explains that grounding and bonding deficiencies can compromise fault clearing, increase shock risk, interfere with sensitive equipment and affect protective device operation.

Commissioning checks may include:

• Visual inspection
• Continuity testing
• Grounding conductor verification
• Bonding checks
• Ground resistance testing where applicable
• Point-to-point resistance testing
• Verification against drawings
• Confirmation of grounding design intent

In Canada, grounding and bonding must be checked against the project design, CSA C22.1 Canadian Electrical Code requirements as adopted in the applicable jurisdiction, local amendments and AHJ expectations. CSA C22.1:24 applies to electrical work and equipment in installations for buildings, structures and premises, with certain exceptions such as utility installations and Transport Canada-regulated ship electrical systems.

Protective Device Misconfiguration

Modern electrical systems depend heavily on protective devices.

During commissioning, teams may find that devices are:

• Left at factory default settings
• Wired incorrectly
• Programmed incorrectly
• Set to the wrong pickup value
• Set to the wrong delay
• Not coordinated with upstream or downstream devices
• Assigned the wrong CT ratio
• Missing relay logic
• Missing trip outputs
• Not communicating
• Not matching the arc flash study
• Not matching the coordination study
• Not matching the project specification

The original JM Test article notes that breakers, relays and fuses may be found improperly set, incorrectly wired or left in factory default configurations, which can cause failure to operate during faults or nuisance trips during normal operation.

Protective device commissioning may include:

• Review of relay settings
• Breaker testing
• Secondary injection testing
• Primary injection testing where required
• Trip circuit checks
• CT polarity and ratio verification
• Fuse verification
• Coordination study comparison
• Functional trip testing
• Communication checks
• Alarm checks
• Lockout and interlock testing

Protection errors are serious because they affect how the system responds during faults.

A system can be fully energized and still be poorly protected if the settings are wrong.

Control Wiring and Logic Errors

Control wiring errors are common in systems with automation, interlocks, starters, PLCs, relays, drives, metering and monitoring.

Common problems include:

• Crossed conductors
• Incorrect terminations
• Wrong terminal numbers
• Wrong control voltage
• Missing jumpers
• Incorrect relay contacts
• Incorrect interlock logic
• Incorrect field device wiring
• Wrong input/output mapping
• Incorrect alarm logic
• Incorrect fail-safe position
• Incorrect start/stop sequence
• Wrong permissive signal
• Poor documentation

The source article explains that control wiring and logic errors can prevent equipment from operating, cause unexpected shutdowns or create unsafe conditions, and that functional testing during commissioning identifies these failures before systems enter continuous service.

Functional testing should check the system as it will actually operate.

That means testing:

• Local controls
• Remote controls
• Interlocks
• Trips
• Alarms
• Permissives
• Emergency stops
• Start and stop sequences
• Reset logic
• Fail-safe behaviour
• Communication status
• Control room indication
• Operator interface messages

A continuity check may prove a wire is connected. It does not prove the control logic is correct.

Equipment Damage from Shipping, Storage or Installation

Electrical equipment can be damaged before startup.

Damage may happen during:

• Shipping
• Offloading
• Storage
• Weather exposure
• Crane or forklift movement
• Rough handling
• Cable pulling
• Installation
• Field modifications
• Cleaning
• Construction activity near equipment
• Water ingress
• Dust exposure
• Incorrect temporary power use

The source JM Test article explains that transformers, breakers and switchgear may experience mechanical stress that does not immediately show visible symptoms, and that commissioning tests such as insulation resistance, functional operation and mechanical checks can help identify latent damage before energization.

Examples include:

• Cracked bushings
• Loose hardware
• Damaged bus
• Damaged insulation
• Misaligned breaker mechanisms
• Damaged CT wiring
• Contaminated compartments
• Moisture inside enclosures
• Damaged door interlocks
• Bent panels
• Compromised seals
• Damaged cable entries

Finding this before energization can prevent more serious failure and may support warranty or project closeout discussions.

Improper Torque and Mechanical Assembly Issues

Electrical reliability depends on mechanical assembly.

Many commissioning problems are not caused by electrical design. They are caused by physical assembly details.

Common issues include:

• Loose bus joints
• Missing hardware
• Loose supports
• Misaligned drawout breakers
• Loose cable lugs
• Incorrect fastener torque
• Missing washers
• Incorrect compression lugs
• Poorly seated connectors
• Loose panel hardware
• Unsecured conductors
• Damaged cable supports
• Misaligned doors or interlocks

The source article notes that improper mechanical assembly can affect electrical performance, especially in large assemblies such as switchgear lineups and motor control centres.

Mechanical checks may include:

• Visual inspection
• Torque verification where specified
• Breaker racking checks
• Door and interlock checks
• Cable support inspection
• Bus joint inspection
• Grounding hardware checks
• Manufacturer checklist review

Do not treat mechanical checks as a formality. A loose joint can become an electrical failure once the system carries load.

Incorrect Equipment Ratings or Mismatched Components

Commissioning may reveal that installed equipment does not match the design.

This can happen because of:

• Procurement substitutions
• Last-minute field changes
• Documentation errors
• Incorrect part selection
• Wrong voltage rating
• Wrong interrupting rating
• Wrong fuse class
• Wrong CT ratio
• Wrong transformer ratio
• Wrong meter input
• Wrong breaker frame
• Wrong trip unit
• Wrong cable type
• Wrong enclosure rating
• Wrong environmental rating
• Wrong hazardous-area rating
• Wrong communication module

The source article explains that incorrect voltage ratings, short-circuit ratings or incompatible components can compromise safety and compliance, and that commissioning verification helps ensure installed equipment matches design intent before it becomes operationally embedded.

Canadian teams should verify ratings against:

• Approved drawings
• Single-line diagrams
• Equipment schedules
• Short-circuit study
• Coordination study
• Arc flash study
• Manufacturer data
• CSA C22.1 requirements where applicable
• AHJ requirements
• Owner specifications
• Site conditions

A mismatch found during commissioning is frustrating.

A mismatch found after failure is worse.

Software and Firmware Configuration Issues

Electrical systems are increasingly digital.

Commissioning now often includes:

• Protective relays
• Smart meters
• Power quality meters
• SCADA gateways
• PLCs
• HMIs
• Remote I/O
• VFDs
• Soft starters
• UPS systems
• Battery systems
• Building automation interfaces
• Network switches
• Communication modules
• Digital trip units

The source JM Test article notes that protective relays, meters and monitoring systems may ship with outdated firmware, default configurations, improper communication settings or unconfigured alarms.

Software and firmware issues may cause:

• Missing alarms
• Incorrect readings
• Poor visibility
• Incorrect trip logic
• Communication failures
• Time-sync issues
• Data logging gaps
• SCADA mapping errors
• Security gaps
• Nuisance trips
• Failed functional testing

Commissioning should verify that settings, firmware, communication, alarms and data points match the approved design and owner requirements.

Documentation and Labelling Discrepancies

Commissioning often finds that the field installation and documentation do not match.

This may include:

• Incorrect labels
• Missing labels
• Outdated drawings
• Incorrect panel schedules
• Wrong cable tags
• Incorrect breaker names
• Unmarked control wiring
• Incorrect terminal numbers
• Missing as-built changes
• Wrong equipment IDs
• Unrecorded field modifications
• Wrong alarm descriptions
• Wrong asset numbers
• Mismatched single-line diagrams

The source article notes that documentation and labelling discrepancies may not look like electrical failures, but they create operational and safety problems if left unresolved.

Good documentation helps future workers isolate equipment, troubleshoot problems, select PPE, understand protection settings, verify energy sources and maintain the system safely.

Poor documentation can turn a simple maintenance task into a high-risk investigation.

Why These Failures Matter

Startup and commissioning failures matter because they can lead to:

• Project delays
• Rework
• Failed acceptance tests
• Equipment damage
• Nuisance trips
• Safety incidents
• Arc flash risk
• Shock risk
• Process downtime
• Warranty disputes
• Contractor call-backs
• Poor owner confidence
• Higher maintenance cost
• Early-life failures

The source JM Test article explains that failures left uncorrected can lead to premature equipment failure, increased maintenance cost, safety incidents and unplanned downtime.

Commissioning is a quality-control checkpoint.

It protects people, equipment and the project schedule.

Canadian Electrical Safety Context

Commissioning work can involve energized equipment, exposed parts, stored energy, rotating equipment, temporary power, testing circuits and complex switching.

Electrical safety planning is not optional.

CSA Z462:24 reorganized requirements for establishing an electrically safe work condition, revised the exception to align with Canadian occupational health and safety language when establishing that condition is “not practicable,” and added that absence of voltage must be verified at each point of work.

Commissioning teams should confirm:

• Qualified worker requirements
• Shock and arc-flash risk assessment
• Energized work authorization
• Switching procedure
• Lockout requirements
• Temporary grounding requirements where applicable
• PPE requirements
• Test instrument ratings
• Boundaries and barricades
• Communication plan
• Emergency plan
• Permit requirements
• Owner site rules
• Manufacturer instructions

CCOHS says electrical tools and equipment should have certification markings from an agency accepted by the jurisdiction, only qualified individuals should work on or maintain electrical equipment, and equipment used in wet or damp locations should be connected to a GFCI where required.

Canadian Code and AHJ Context

For Canadian projects, avoid writing the article as if NFPA 70 or OSHA are the governing framework.

Use Canadian framing.

The applicable framework may include:

• CSA C22.1 Canadian Electrical Code
• Provincial or territorial electrical codes
• Local amendments
• Electrical inspection authority requirements
• Authority having jurisdiction requirements
• CSA Z462 workplace electrical safety practices
• Owner specifications
• Utility requirements
• Manufacturer instructions
• Project commissioning specifications
• NETA standards where specified by the project
• Engineering design documents

CSA C22.1:24 applies to electrical work and equipment operating or intended to operate at all voltages in electrical installations for buildings, structures and premises, with listed exceptions.

Always confirm the adopted code edition and AHJ requirements for the province, territory and site.

The Role of NETA Standards

NETA standards are often used as technical commissioning and acceptance-testing references, especially for electrical power equipment and systems.

The source article refers generally to industry standards, including testing guidance from organizations such as IEEE. For Canadian localization, NETA should be presented as a technical or project-specification reference, not as a replacement for Canadian codes or AHJ requirements.

ANSI/NETA ATS is developed for those assessing the suitability of newly installed electrical power equipment and systems for initial energization, and its purpose is to specify field tests and inspections that help ensure equipment performs satisfactorily.

ANSI/NETA ECS-2024 focuses on electrical commissioning specifications, and the ANSI listing explains that acceptance testing provides baseline results for maintenance and trending, while commissioning verifies that the electrical equipment and system meet the owner’s project requirements and basis of design.

For Canadian projects, NETA can be very useful when specified by the owner, engineer or contract documents.

Commissioning vs Reactive Troubleshooting

Commissioning finds problems before the system becomes business-critical.

Reactive troubleshooting finds problems after the system is already expected to work.

The source JM Test article explains that without proper commissioning, many electrical failures surface only after systems are in use, making troubleshooting more disruptive and expensive.

Commissioning helps teams:

• Test in a controlled sequence
• Document baseline results
• Correct installation problems
• Verify protection settings
• Confirm system operation
• Reduce early-life failures
• Improve closeout quality
• Reduce call-backs
• Improve owner confidence
• Support future maintenance

Reactive troubleshooting usually happens under pressure.

Commissioning gives the team time to find and fix issues before operations depend on the system.

Electrical Tests Commonly Used During Commissioning

The exact test plan depends on the equipment and project specification, but commissioning may include:

Insulation Resistance Testing

Used for cables, motors, transformers and other equipment to identify insulation problems and establish baseline values.

Contact Resistance Testing

Used for bus joints, breaker contacts, switchgear and high-current connections.

Ground Resistance and Bonding Tests

Used to verify grounding and bonding continuity, electrode resistance where applicable and grounding system performance.

Phase Rotation Testing

Used to confirm correct phase sequence before motor operation or system connection.

Power Quality Measurements

Used to check voltage, current, harmonics, imbalance, transients or other conditions that may affect startup.

Protective Relay Testing

Used to verify settings, logic, trip outputs, inputs, alarms, CT circuits and communication.

Circuit Breaker Testing

Used to check trip units, timing, contact resistance, mechanical operation and protection performance where required.

Thermal Imaging

Used after energization and load where appropriate to identify hot spots, loose connections or overloaded components.

Functional Testing

Used to verify controls, alarms, trips, interlocks, permissives and operating sequences.

Documentation Review

Used to confirm drawings, labels, test forms, settings, certificates and as-built records.

JM Test Canada’s calibration services page lists electrical test equipment capabilities including insulation testers, hipot testers, low-ohm resistance testers, earth ground resistance testers, circuit breaker test sets, voltage and current recorders, power quality analyzers, relay test equipment and transformer test equipment.

Equipment That Should Be Checked Before Commissioning

Commissioning is not only for large switchgear.

The process may involve many types of equipment, including:

• Main switchgear
• Distribution switchboards
• Panelboards
• Motor control centres
• Transformers
• Busway
• Cables
• Breakers
• Relays
• Fuses
• Disconnect switches
• Transfer switches
• UPS systems
• Generators
• Battery systems
• Variable frequency drives
• Soft starters
• Motors
• Grounding systems
• Control panels
• SCADA panels
• Metering panels
• Fire pump controllers
• Building automation interfaces
• Communications equipment

Each equipment type needs the right test method.

A one-size-fits-all commissioning checklist is not enough.

Canadian Industries Where Commissioning Failures Matter

Industrial Plants

Manufacturing facilities, mills, food plants, refineries and process facilities rely on commissioning to reduce startup delays and prevent equipment damage.

Oil and Gas

Refineries, terminals, gas plants, compressor stations and pipeline facilities often have complex electrical systems with high downtime costs.

Mining

Mines rely on motors, drives, crushers, conveyors, substations, pumps and control systems in harsh environments.

Utilities

Substations, distribution systems, generation assets and control systems need verified protection, grounding, communications and documentation.

Data Centres

Power reliability is critical. Commissioning helps verify switchgear, UPS systems, transfer systems, generators, batteries, monitoring and failover logic.

Commercial Buildings

Large buildings need reliable distribution, emergency power, fire pump systems, life safety systems, controls and metering.

Healthcare and Education

Hospitals, universities and public buildings need reliable electrical systems and accurate documentation for maintenance and emergency response.

What Contractors Gain From Finding Failures Early

Electrical contractors benefit when commissioning is treated seriously.

Finding issues early helps:

• Reduce call-backs
• Protect reputation
• Improve project closeout
• Avoid late-stage disputes
• Reduce rework under pressure
• Support warranty discussions
• Improve owner trust
• Improve installation practices
• Provide better documentation
• Make future projects smoother

The source article states that contractors benefit from identifying commissioning failures early because it reduces call-backs, protects reputation and strengthens relationships with owners and engineers.

A failed test during commissioning is not always bad news.

It is often proof that the process is working.

What Owners Gain From Strong Commissioning

Owners benefit because commissioning reduces the chance that hidden installation issues become operational failures.

A strong commissioning process can support:

• Safer energization
• Better reliability
• Lower early maintenance burden
• Better documentation
• Clearer asset baselines
• Fewer surprise failures
• Better staff training
• Cleaner handover
• More confidence in critical systems

The original article explains that commissioning acts as a quality control checkpoint and protects both people and assets.

Owners should insist on useful documentation, not only a statement that equipment was “checked.”

Commissioning Documentation Checklist

A useful commissioning package may include:

• Approved test plan
• Equipment list
• Single-line diagrams
• As-built drawings
• Protection settings
• Coordination study reference
• Arc flash study reference
• Equipment nameplate photos
• Test instrument certificates
• Insulation resistance results
• Contact resistance results
• Grounding and bonding results
• Phase rotation records
• Breaker test results
• Relay test results
• Functional test forms
• Deficiency log
• Corrective action records
• Re-test results
• Final acceptance signoff
• Labels and panel schedules
• Operation and maintenance manuals
• Baseline readings for future maintenance

Documentation is not paperwork for the sake of paperwork.

It is how future workers understand what was built, what was tested and what changed.

Common Commissioning Mistakes to Avoid

Treating Visual Inspection as Enough

Visual inspection is important, but it does not prove electrical performance.

Energizing Before Test Results Are Reviewed

Testing must be reviewed by qualified people before energization decisions are made.

Skipping Phase Rotation Checks

A simple phase rotation error can create mechanical damage or startup delays.

Ignoring Grounding and Bonding

Grounding and bonding deficiencies can affect shock risk, fault clearing and equipment performance.

Using Uncalibrated Test Equipment

Commissioning results depend on trustworthy test instruments and valid calibration records.

Leaving Protective Devices at Default Settings

Factory defaults rarely represent the final system design.

Not Testing Control Logic

Controls may appear wired correctly but still operate incorrectly.

Not Re-Testing After Corrections

If a deficiency is corrected, the relevant test should be repeated and documented.

Ignoring Software and Communication Settings

Modern electrical systems need verification of firmware, networks, time sync, alarms and data points.

Failing to Update As-Builts

A corrected field issue that is not documented becomes a future maintenance hazard.

Test Equipment and Rental Support for Commissioning

Commissioning projects often require equipment that a contractor or owner may not use every day.

Rental may make sense for:

• Power quality analyzers
• Insulation testers
• Ground resistance testers
• Low-resistance ohmmeters
• Relay test sets
• Circuit breaker test sets
• Thermal cameras
• Phase indicators
• Hipot testers
• Cable fault locators
• Data loggers
• Current recorders
• Load banks where required
• Fibre and communication testers
• Gas monitors for certain work environments

JM Test Canada’s rental page states that its rental division includes instrument and controls, electrical, communications, gas detection, utility products and mechanical equipment.

For a Canadian article, keep exact availability conditional and ask customers to confirm the required model, accessories, calibration certificates, rental term and shipping timeline before booking.

JM Test Systems Canada Support

JM Test Canada can support commissioning teams with test equipment, calibration services and rental options where available.

Its Canadian calibration services page lists electrical test equipment calibration categories including insulation testers, hipot testers, low-ohm resistance testers, earth ground resistance testers, circuit breaker test sets, power quality analyzers, relay test equipment and transformer test equipment.

The same page also describes onsite and mobile calibration lab services, customer portal access, QR-coded certificates, traceable certificates, calibration stickers, as-found/as-left data and retest notices.

For the Canadian page, avoid copying US-only service, location or standards wording from the source article. Confirm current Canadian availability, service scope, certificate type, rental stock and turnaround time before publishing firm claims.

Practical Takeaway

Startup and commissioning are designed to find problems early.

Common electrical failures include:

• Loose connections
• Incorrect phase rotation
• Insulation resistance failures
• Grounding and bonding deficiencies
• Protective device misconfiguration
• Control wiring errors
• Equipment damage
• Mechanical assembly issues
• Incorrect ratings
• Software and firmware problems
• Documentation and labelling discrepancies

The original JM Test article summarizes the point well: commissioning finds problems before they find you, and failures such as loose connections, insulation damage, grounding deficiencies and protection misconfiguration are easier to correct before systems enter service.

For Canadian teams, the best commissioning process is planned, documented and aligned with the project specification, CSA C22.1 where applicable, CSA Z462-informed electrical safety practices, manufacturer instructions, owner requirements and AHJ expectations.

JM Test Systems Canada can support commissioning work with calibration services, electrical test equipment, rental equipment and documentation support where available. Confirm the exact equipment, accessories, calibration certificates, rental terms and Canadian service details before booking.