Technical Power Quality Analysis Surveys

For Consulting Engineers & Facility Managers (Northern Ireland & UK)

Our Power Quality Analysis Surveys provide detailed, standards-aligned electrical performance assessments for low-voltage (LV) and selected high-voltage (HV/LV interface) installations. The service is specifically structured to support consulting engineers, facilities managers, and asset owners requiring defensible data for compliance, fault investigation, system design validation, and DNO engagement.

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Standards & Regulatory Framework

All measurements and reporting align with applicable UK and European standards, including:

• BS 7671 (IET Wiring Regulations)

• Electricity Safety, Quality and Continuity Regulations 2002 (ESQCR)

• EN 50160 – Voltage characteristics of public distribution systems

• IEC 61000-4-30 Class A – Power quality measurement methods

• IEC 61000-4-7 / 4-15 – Harmonic and flicker measurement techniques

Where required, survey findings are benchmarked against:

• DNO supply quality obligations

• Contractual supply agreements

• Design-stage performance assumptions

• Manufacturer equipment tolerance limits

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Instrumentation & Measurement Integrity

We deploy IEC 61000-4-30 Class A compliant three-phase power quality analysers suitable for compliance investigations and dispute resolution.

Instrumentation capability includes:

• Simultaneous 3-phase voltage and 4-current measurement

• True RMS measurement with high sampling rates

• Harmonic analysis typically to the 50th order (higher on request)

• Interharmonic and subharmonic analysis

• Voltage unbalance (negative sequence component)

• Flicker (Pst and Plt)

• Transient capture with sub-cycle resolution

• Inrush current recording

• Event-triggered waveform capture

Flexible Rogowski coils and calibrated clamp CTs allow non-intrusive installation within live LV distribution systems (commonly 400/230V, 50Hz UK supply).

All equipment is maintained under calibration traceable to recognised standards (UKAS traceability available where required).

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Parameters Assessed

Typical monitored parameters include:

Voltage Characteristics

• Phase-to-phase (nominal 400V)

• Phase-to-neutral (nominal 230V)

• RMS variation and statistical distribution

• Frequency deviation (nominal 50Hz ± statutory tolerance)

• Short-duration dips and swells

• Rapid voltage changes

Harmonics & Distortion

• Total Harmonic Distortion (THDv / THDi)

• Individual harmonic magnitudes

• Harmonic phase angle

• Neutral current harmonic content (triplen harmonics)

• K-factor implications for transformers

System Performance

• Voltage unbalance (%)

• Power factor (displacement and true)

• Active, reactive, and apparent power

• Maximum demand and load diversity

• Crest factor and waveform distortion

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Typical Engineering Applications

Our technical surveys support:

• Harmonic risk assessments for new VSD installations

• Transformer overheating investigations

• Neutral conductor overloading analysis

• UPS and generator compatibility studies

• EV charging infrastructure impact assessments

• Solar PV grid interaction analysis

• Recurrent breaker tripping investigations

• Compliance verification for new builds or refurbishments

• Evidence preparation for DNO supply quality discussions

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Methodology

1. Technical Scope Definition

Review of single-line diagrams, protection coordination, load schedules, and known issues.

2. Monitoring Strategy

Placement at:

• Main LV switchboard incomer

• Sub-distribution boards

• Critical loads (e.g., data halls, process lines)

• Transformer secondary terminals

Monitoring duration typically ranges from 7 to 28 days, depending on load variability and investigation objectives.

3. Data Acquisition

High-resolution logging with event-triggered waveform capture to ensure no transient or short-duration disturbance is missed.

4. Data Analysis & Interpretation

Using specialist power quality software to:

• Perform harmonic spectrum analysis

• Assess compliance against EN 50160 thresholds

• Evaluate statistical percentiles (e.g., 95% voltage values)

• Identify root-cause correlations between load behaviour and disturbance events

5. Engineering Report

The final report includes:

• Executive technical summary

• Single-line diagram reference points

• Tabulated statistical voltage analysis

• Harmonic spectrum plots

• Event logs (dips, swells, transients)

• Load demand profiles

• Compliance assessment

• Root cause findings

• Prioritised remedial recommendations

All findings are presented in a format suitable for inclusion in design documentation, insurance submissions, or regulatory discussions.

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Remedial Engineering Support

Where deficiencies are identified, we provide technical guidance on:

• Passive or active harmonic filtering

• Power factor correction systems (fixed or automatic)

• Transformer re-rating or K-rated specification

• Neutral conductor upgrades

• Load redistribution strategies

• Surge Protection Device (SPD) optimisation

• Supply capacity and diversity reassessment

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Why This Matters for Facilities & Asset Management

For facilities managers and consulting engineers, robust power quality data enables:

• Reduced lifecycle asset costs

• Improved system resilience

• Evidence-based capital planning

• Reduced risk of equipment warranty disputes

• Stronger position in DNO negotiations

• Demonstrable regulatory compliance

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Northern Ireland & UK Coverage

We operate across Northern Ireland and mainland UK, delivering technical surveys for industrial, commercial, healthcare, education, and infrastructure projects