Non-linear loads such as drives, UPS systems, rectifiers, and LED drivers inject harmonic currents into the network. Harmonics show themselves as capacitor failures, transformer and cable heating, neutral conductor overload, and unexpected stoppages of sensitive devices. Harmonic filter panels limit this distortion at the source, bringing power quality back to an operable level.
Miratek selects filters by measurement, not assumption; the harmonic spectrum is captured with a power analyzer recording, and a passive or active filter solution is sized to the dominant harmonic orders. Target values are defined against recognized references such as IEEE 519. After commissioning, a verification measurement is taken from the same point and the result is reported comparatively.
Technical Scope Summary
| Voltage level | 400 V LV networks |
| Filter types | Passive filters, active harmonic filters, and hybrid solutions |
| Target quantities | Limiting the total harmonic distortion (THD) of current and voltage |
| Reference | IEEE 519 recommended values and grid connection requirements |
| Application areas | Drive-intensive facilities, data centers, UPS-fed systems, welding shops |
| Delivery model | Turnkey including measurement, sizing, manufacturing, and commissioning |
How We Work
Harmonic measurement
The harmonic spectrum and load profile are recorded at the facility with a power analyzer.
Analysis and sizing
The dominant harmonic orders are identified, and a passive or active filter solution is sized to the target THD value.
Panel manufacturing
The filter panel is manufactured in the workshop in accordance with thermal layout and ventilation criteria.
Installation and connection
The panel is installed on site; the current transformers and power connections are made.
Verification measurement
After commissioning, the THD values are verified at the same measurement point and a comparative report is presented.
Scope of Work
- Harmonic measurement and reporting with a power analyzer
- Passive and active harmonic filter sizing
- Filter panel manufacturing and factory tests
- Compatibility analysis with existing compensation systems
- Site installation and commissioning
- Post-commissioning comparative verification measurement
Frequently Asked Questions
Should we choose an active or a passive filter?
The decision depends on the measurement result. If the dominant harmonics concentrate at specific orders and the load profile is relatively stable, a passive filter is an economical solution; with variable loads and broad-spectrum distortion, an active filter is more effective. We present a comparison of the two options together with the measurement report.
How do we know whether we have a harmonic problem?
Frequent capacitor failures, unexplained thermal trips, overheating in transformers and cables, and high current on the neutral conductor are the typical symptoms. A definitive diagnosis requires measurement with a power analyzer. The measurement result pins down the source of the problem and the solution options.
Does installing a filter halt production?
Since the panel is manufactured in the workshop, site work is limited to connection and commissioning. The short power outage needed for the connection is planned together with the operator and is usually completed within a planned shutdown window.
Quick Facts
- Category: Low Voltage Panel Services
- Turnkey delivery
- ISO 9001 quality assurance
