- Why You Received That Notice
- What to Do Immediately — Step-by-Step
- What the CEA Regulation Actually Says
- What Gets Measured — The Three Tests
- Technical Limits & Standards
- Who Is Required to Comply?
- What Happens If You Don’t Comply?
- How Elion Conducts Your Testing
- Our Services in Full
- Frequently Asked Questions
- Get Compliant with Elion
Why You Received That Notice — And Why It’s Urgent
If you are a Wind or Solar Power Developer or Generator connected to the grid anywhere in India, there is a strong chance you have recently received — or are about to receive — a formal letter from your State Load Dispatch Centre (SLDC), Maharashtra State Load Dispatch Centre (MSLDC), or a Regional Load Dispatch Centre (RLDC) demanding that you submit an Annual Power Quality Test Report.
MSLDC, for instance, issued a communication (Ref. CE/MSLDC/REMC-OP/CEA comp/ dated 16 March 2026) addressed to all RE Generators and RE Developers in the state, marked MOST URGENT, demanding submission of a testing schedule by 31-03-2026. Similar drives are underway across other states and WRPC / ERPC / NRPC / SRPC sub-committees.
⚠️ This is not a new regulation. The Annual Power Quality measurement mandate has existed since 2007 and was reinforced by the CEA (Amendment) Regulations 2019. What is new is that SLDCs and RLDCs are now actively enforcing it — and treating non-submission as a regulatory violation with consequences.
The WRPC RE Sub-Committee has recorded serious concern about continued non-compliance at state level. The CEA Working Group (June 2023) has reiterated that power quality measurements must be carried out at least once a year and the assessment report submitted to CEA/RPC, CTU and POSOCO annually after commissioning.
In short: compliance is mandatory, overdue, and now actively monitored.
What You Should Do Immediately After Receiving an SLDC Notice
If you have received a notice from MSLDC, any state SLDC, or an RLDC demanding power quality compliance, here is the exact sequence of steps to take — in order, without delay.
1. Do This Today
Submit Your Testing Schedule to the SLDC
The most urgent requirement in most SLDC notices — including MSLDC’s March 2026 notice — is not the test report itself, but the Testing Schedule and Timeline. You must formally inform your SLDC of the date you will conduct the measurement and when you will submit the final report. Failure to submit this schedule by the deadline (31-03-2026 for MSLDC) is itself treated as non-compliance. Draft this letter and send it immediately.
💡 Elion can draft and submit this letter for you within 24 hours of engagement.
2. Do This Within 48 Hours
Appoint a Qualified Power Quality Testing Agency
CEA regulations require that testing be conducted by an agency using NABL-traceable, calibrated instruments — and in presence of all concerned parties. Do not attempt this with uncertified in-house meters. Identify and formally appoint a qualified testing agency immediately so that site mobilisation can be scheduled. This step determines how quickly you can complete the testing and meet your committed timeline.
💡 Elion is NABL-traceable, pan-India deployable, and can confirm your test date within 48 hours.
3.On Scheduled Test Date
Conduct On-Site Measurement at Your Point of Interconnection (POI)
The three CEA-mandated measurements — Harmonic Current Injection (per IEEE 519), DC Current Injection (≤ 0.5% rated output), and Voltage Flicker (per IEC 61000-4-15) — must all be measured at your plant’s Point of Interconnection. This must be done with all parties present: your representative and the grid utility’s representative. The measurement campaign typically takes 1–2 days on site.
💡 Elion coordinates party attendance, brings all instruments, and handles site logistics end-to-end.
4. Within 7 Days of Testing
Prepare the Power Quality Compliance Report
Raw measurement data must be analysed and compiled into a formal Power Quality Assessment Report — including measurement methodology, instrument calibration certificates, harmonic spectrum data, DC injection percentages, flicker indices (Pst and Plt), comparison against all regulatory limits, and a signed Statement of Compliance. This is the document the SLDC, CTU and CEA actually want to see.
💡 Elion delivers a complete, submission-ready report within 5–7 working days of site measurement.
5. Final Step — Close the Loop
Submit Report to SLDC, RPC, CTU & POSOCO
As mandated by the CEA Working Group (2022) and RLDC circulars, the completed Annual Power Quality Assessment Report must be submitted to five authorities: (1) your State Load Despatch Centre (SLDC), (2) your Regional Power Committee (WRPC / SRLDC / NRLDC / ERLDC as applicable), (3) Central Transmission Utility (CTU / PGCIL), (4) POSOCO / NLDC, and (5) CEA. Obtain written acknowledgement from each. Retain a compliance register — this evidence is critical if your plant is audited.
💡 Elion provides submission support to all five authorities and maintains your compliance documentation.
✅ Typical total timeline with Elion: Testing schedule submitted within 24 hrs → site measurement within 10–14 days → full compliance report delivered within 21 days of engagement. Fully compliant, fully documented.
What the CEA Regulation Actually Says
The governing regulation is the CEA (Technical Standards for Connectivity to the Grid) (Amendment) Regulations, 2019, published on 6 February 2019 in the Official Gazette of India. It amends the original 2007 Regulations and is mandatory for all Wind Generating Stations and generating stations using inverters (solar, hybrid, BESS) connected to the grid.
Clause B1(4) of Part-II of the CEA Technical Standards for Connectivity to the Grid states:
Measurement of harmonic content, DC injection and flicker shall be done at least once in a year in presence of the parties concerned and the indicative date for the same shall be mentioned in the connection agreement; Provided that in addition to annual measurement, if distribution licensee or transmission licensee or the generating company, as the case may be, desires to measure harmonic content or DC-injection or flicker, it shall inform the other party in writing and the measurement shall be carried out within 5 working days.
— CEA (Technical Standards for Connectivity to the Grid) Regulations, Clause B1(4), Part-II
The CEA Working Group’s 2022 Final Report further mandated that power quality assessment reports be submitted annually to CEA, RPC, CTU, and POSOCO post-commissioning. The SRLDC has also issued a formal procedure document for conducting Harmonics, DC Current and Flicker Testing that guides the measurement protocol.
📌 Key takeaway: If your plant is connected to the grid — at 33 kV or above — and uses inverters or wind turbines, you are legally required to conduct and report these measurements every calendar year. There is no opt-out provision.
What Gets Measured — The Three Tests Explained
The annual power quality test under CEA regulations covers three distinct measurements, all conducted at the Point of Interconnection (POI) — the physical point where your RE plant connects to the transmission grid.
1. Harmonic Current Injection IEEE 519
Inverter-based generators (solar, wind) inject non-sinusoidal current waveforms into the grid. These harmonics — integer multiples of the 50 Hz fundamental frequency — can cause transformer overheating, nuisance tripping, and interference with protection systems. The CEA mandates that harmonic current injection from a generating station must not exceed the limits specified in IEEE Standard 519. Total Harmonic Distortion (THD) of voltage at the interconnection point must not exceed 5%.
🔬 How it is measured: A calibrated power quality analyser is connected at the POI and records current and voltage waveforms over a defined measurement window. A Fast Fourier Transform (FFT) analysis yields individual harmonic magnitudes up to typically the 50th order.
2. DC Current Injection ≤ 0.5% Rated Output
Inverters can introduce a small DC component into the AC output. Even low-level DC injection causes transformer saturation, increased losses, accelerated insulation degradation and, in extreme cases, corrosion of grounding electrodes. The CEA regulation stipulates that the generating station shall not inject DC current greater than 0.5% of the full rated output at the Point of Interconnection.
🔬 How it is measured: Specialised sensors capable of resolving DC components in the milliamp range are used at the POI. The DC injection is expressed as a percentage of the plant’s full rated AC output current.
3. Voltage Flicker IEC 61000
Flicker refers to rapid, repetitive fluctuations in voltage that cause perceptible changes in light intensity — the “flicker” seen in lighting loads — and can disturb sensitive industrial processes. Wind plant output variation with turbulence, and solar plant response to cloud transients, can introduce flicker. The CEA mandates that flicker injection must not exceed limits specified in IEC 61000-3-7 and IEC 61000-4-15.
The key flicker metrics are the Short-term Perceptibility index (Pst) and Long-term Perceptibility index (Plt), measured using a flickermeter conforming to IEC 61000-4-15.
🔬 How it is measured: A flickermeter or power quality recorder with IEC 61000-4-15 compliant firmware measures voltage fluctuations continuously over a 10-minute (Pst) and 2-hour (Plt) window.
Technical Limits at a Glance
| Parameter | Governing Standard | Permissible Limit | Measurement Location |
|---|---|---|---|
| Harmonic Current Injection | IEEE Standard 519 | As per IEEE 519 tables for applicable short-circuit ratio; Voltage THD ≤ 5% at POI | Point of Interconnection (POI) |
| DC Current Injection | CEA Reg. Clause B1(4) | ≤ 0.5% of full rated output current | Point of Interconnection (POI) |
| Voltage Flicker (Pst) | IEC 61000-3-7 / IEC 61000-4-15 | Pst ≤ 1.0 (short-term, 10-min window) | Point of Interconnection (POI) |
| Voltage Flicker (Plt) | IEC 61000-3-7 / IEC 61000-4-15 | Plt ≤ 0.65 (long-term, 2-hour window) | Point of Interconnection (POI) |
| Measurement Frequency | CEA Regulations, Clause B1(4) | At least once per calendar year | In presence of all concerned parties |
| On-demand measurement | CEA Regulations, Clause B1(4) Proviso | Within 5 working days of written request | Point of Interconnection (POI) |
| Report Submission | CEA WG Report 2022 / RLDC circulars | Annually to CEA, RPC, CTU, POSOCO and state SLDC | — |
Who Is Required to Comply?
The CEA (Technical Standards for Connectivity to the Grid) Amendment Regulations 2019 apply to:
- ✅ All Wind Generating Stations connected to the grid, irrespective of capacity or vintage, under Part-II (B) of the CEA Regulations.
- ✅ All Solar PV Generating Stations (inverter-based) connected to the grid, including rooftop, ground-mounted utility-scale and hybrid configurations.
- ✅ Hybrid RE Projects and BESS-integrated plants commissioned under the 2019 Amendment framework.
- ✅ Plants commissioned before February 2019 are equally covered. The 2019 Amendment did not grandfather older plants out of the annual measurement obligation — it reinforced it.
Whether your plant is in Maharashtra, Rajasthan, Gujarat, Karnataka, Andhra Pradesh, Tamil Nadu, Madhya Pradesh or any other state — the CEA is a central authority and these regulations apply uniformly across India. Every SLDC, from MSLDC to KPTCL, and every RLDC, from WRLDC to SRLDC, is now circulating compliance notices.
⚠️ Important: The obligation applies at the plant level, not per inverter or per WTG. The measurement is conducted at the main Point of Interconnection where the plant connects to the grid.
What Happens If You Don’t Comply?
Non-compliance is not a matter of paying a small administrative fine. The regulatory stakes are significant and escalating. SLDCs have explicitly stated that non-submission will be “viewed seriously” and will attract appropriate action under applicable regulatory provisions.
| Risk Category | Specific Consequence |
|---|---|
| Regulatory Action | Show cause notice, penalty proceedings by SERC / CERC under the Electricity Act 2003 |
| Grid Connectivity | Risk of disconnection from the grid; delays in connectivity agreement renewal or amendment |
| PPA & Offtake | Non-compliance findings can trigger PPA breach provisions; revenue loss during regulatory dispute |
| CTU / STU Agreements | Discrepancies in compliance documents can halt processing of connectivity agreements (CON-5 / CON-6) |
| Audit & Lender Risk | Project lenders and equity investors increasingly require regulatory compliance certificates; non-compliance flags in due diligence |
| Reputational Risk | Named in SLDC/RLDC non-compliance lists; potential publication in regulatory orders |
The WRPC RE Sub-Committee’s formal expression of concern and the MSLDC’s circulation through all Qualified Connecting Agencies (QCAs) signals that enforcement is no longer discretionary. The compliance window is short — and the testing cannot be done overnight. You need to schedule your testing now.
How Elion Conducts Your Annual Power Quality Testing
Elion Technologies and Consulting is an experienced power quality engineering firm with hands-on capability across wind and solar plants throughout India. Our process is structured to get you compliant quickly, with a technically defensible report that satisfies SLDC, RLDC, CTU and CEA requirements.
01. Initial Consultation & Document Review
We review your plant’s connection agreement, existing power quality baseline data (if any), single-line diagram, and the specific notice received from your SLDC/RLDC. We confirm the exact POI, measurement scope, and which parties must be present as per your connection agreement.
02. Testing Schedule Submission to SLDC
We prepare and help you submit the required Testing Schedule and Timeline for Test Report submission to your SLDC — this is the immediate, urgent requirement in most current notices. We draft the communication, ensuring it meets the format expected by your state utility.
03. On-Site Measurement at Your Plant’s POI
Our engineers travel to your plant site with calibrated, NABL-traceable power quality measurement instruments. Measurements are conducted at the Point of Interconnection in the presence of the required parties — your representative, and representatives of the grid utility — exactly as mandated by Clause B1(4). We capture harmonic spectrum, DC injection and flicker data over the prescribed measurement windows.
04. Data Analysis & Compliance Assessment
Raw measurement data is processed in our engineering lab. We apply IEEE 519 harmonic limit analysis, DC injection percentage calculation against your plant’s rated output, and IEC 61000-4-15 flicker index computation (Pst and Plt). Each parameter is assessed against the applicable regulatory limit and documented with pass/fail determination.
05. Formal Power Quality Assessment Report
We produce a comprehensive, professionally formatted Power Quality Assessment Report containing measurement methodology, instrument calibration certificates, raw data appendices, analysis results, comparison with regulatory limits, and a signed Statement of Compliance. The report is prepared in the format required for submission to CEA, RPC, CTU, POSOCO, and your SLDC.
06. Report Submission Support
We assist you in submitting the completed report to all required authorities — your SLDC, the Regional Power Committee (RPC), Central Transmission Utility (CTU / PGCIL), and POSOCO (now NLDC). We track acknowledgement and maintain a compliance register for your plant.
Our Full Suite of CEA Compliance Services
Beyond the mandatory annual measurement, Elion offers a complete range of power quality engineering services to keep your RE plant continuously compliant and grid-ready.
⚡On-Site Annual Power Quality Measurement
- CEA-mandated harmonic, DC injection & flicker measurement at your POI. NABL-traceable instruments, all-party presence, across PAN-India wind & solar plants.
📋 Power Quality Audit & Assessment Report
- Full engineering report with measured data, IEEE 519 & IEC 61000 compliance assessment, instrument certificates — ready for SLDC, RPC, CTU & POSOCO submission.
📅 Testing Schedule & SLDC Correspondence
- Urgent: We draft and help submit your Testing Schedule and Timeline to your SLDC immediately — addressing the 31 March 2026 MSLDC deadline and similar notices.
🎓 CEA Compliance Training
- Customised training for your O&M and engineering teams on CEA grid connectivity requirements, power quality monitoring, and ongoing compliance obligations.
📊 Continuous Power Quality Monitoring
- Permanent or periodic power quality monitoring solutions installed at your POI to proactively detect harmonic or flicker exceedances before regulatory inspections.
🔧 Corrective Action & Mitigation
- Where measurements reveal exceedances, we recommend and support implementation of harmonic filters, reactor solutions or inverter parameter tuning to restore compliance.
Frequently Asked Questions
Don’t Let a Notice Become a Penalty.
Act Today.
Elion Technologies and Consulting is ready to schedule your Annual Power Quality Testing, prepare your SLDC testing schedule submission, and deliver a complete, submission-ready Power Quality Assessment Report — fast, professionally, and across India.