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Power quality · P2-06

Non-Linear Load Harmonic Survey

A systematic survey identifying and quantifying every significant distorting load on a site, so that mitigation is aimed at the actual sources rather than at the point where the symptom shows. On mixed-use buildings the distortion source is frequently on a different floor from the equipment suffering.

What this study establishes.

Inventory of non-linear load by type, rating and location — drives, UPS, rectifiers, lighting drivers, EV chargers, IT load.

Per-circuit spectral measurement at distribution board level.

Contribution ranking showing which loads dominate at each harmonic order.

Triplen harmonic assessment and consequent neutral current on the affected boards.

Distortion map across the installation, tracing propagation from source to point of impact.

Targeted mitigation plan aimed at the dominant contributors.

What the work covers.

A systematic survey identifying and quantifying every significant distorting load on a site, so that mitigation is aimed at the actual sources rather than at the point where the symptom shows. On mixed-use buildings the distortion source is frequently on a different floor from the equipment suffering.

Triplen harmonics sum arithmetically in the neutral rather than cancelling, so a three-phase board with heavily single-phase electronic load can carry a neutral current exceeding phase current. Boards designed with a reduced neutral are the ones at risk.

Deliverables

What lands in your inbox.

01

Inventory of non-linear load by type, rating

Inventory of non-linear load by type, rating and location — drives, UPS, rectifiers, lighting drivers, EV chargers, IT load.

02

Per-circuit spectral measurement at distribution board level

Per-circuit spectral measurement at distribution board level.

03

Contribution ranking showing which loads dominate at

Contribution ranking showing which loads dominate at each harmonic order.

04

Triplen harmonic assessment and consequent neutral current

Triplen harmonic assessment and consequent neutral current on the affected boards.

05

Distortion map across the installation, tracing propagation

Distortion map across the installation, tracing propagation from source to point of impact.

06

Targeted mitigation plan aimed at the dominant

Targeted mitigation plan aimed at the dominant contributors.

Methodology

How we run it.

01

Scope & data capture

We confirm the question the study must answer, agree the measurement or modelling points, and collect what the work depends on: distribution schedule identifying which boards feed which load types; access to circuit-level measurement points across the installation; tenant or department load descriptions in multi-occupancy.

Agreed scope · Named lead engineer
02

Measurement & modelling

Engineers carry out the measurement and modelling on site and in software, under operating conditions representative of the problem rather than a single convenient snapshot.

Calibrated model · Raw records
03

Analysis against standard

Results are assessed against IEC 61000-4-7, IEC 61000-4-30, IEEE 519-2022, with the assessment basis and any measurement uncertainty stated rather than implied.

Compliance position
04

Report & recommendations

You receive a signed engineering report with findings ranked by consequence, the reasoning behind each conclusion, and mitigation options costed so they can be acted on or deferred deliberately.

Signed report · Costed actions
Aligned standards

Assessed against the published limits.

IEC 61000-4-7IEC 61000-4-30IEEE 519-2022IEEE 1159IEC 61000-4-7IEC 61000-4-30IEEE 519-2022IEEE 1159
Notes & Queries

Common questions.

01

Typically in one of these situations: pcc distortion is out of limits but the source is not obvious; mixed-use or multi-tenant building where responsibility needs apportioning; neutral conductors or neutral bars running hot. If none of these apply, the study is unlikely to be the right next step and we will say so.

02

To scope and run the work we need distribution schedule identifying which boards feed which load types; access to circuit-level measurement points across the installation; tenant or department load descriptions in multi-occupancy buildings. Where any of it is missing we can establish it on site, which changes the scope rather than blocking the work.

03

Primarily IEC 61000-4-7, IEC 61000-4-30, IEEE 519-2022, IEEE 1159. The applicable framework depends on your connection agreement and jurisdiction, so we confirm which applies before measurement rather than after.

Ready to start the engagement?

Tell us about your site and the problem you are seeing. We come back with a fixed scope, a fixed fee, and a named lead engineer.