Two plants. 40+ meters. Penalties eliminated, audits simplified — and an expansion order for two more plants.
Client snapshot
| Client | Dairy Day Ice Creams — dairy & ice cream manufacturing |
|---|---|
| Location | Harohalli, Bangalore |
| Facility profile | Multi-VFD ice cream manufacturing — IQF (Instant Quick Freeze), chilling units and cold-room compressors running 24/7 on EB + DG supply across two plants |
| Deployment | Switchology EMS — self-hosted gateways with 40+ digital energy meters across both plants (RS485 Modbus) |
| Status | Live and running. Expansion approved: 2 additional plants, 40+ more meters |
01 · The challenge — before Switchology
Dairy Day runs energy-intensive, round-the-clock manufacturing where refrigeration can never stop. Yet the plants had no live view of their own power. Everything depended on manual effort:
- Meter readings were taken by walking the plant and entering values into log sheets — slow, error-prone, and with no usable trend history.
- Unexpected shutdowns occurred with no data trail to explain what happened or which feeder caused it.
- DG run-hours and units generated were unknown — diesel consumption could not be reconciled, and the EB vs DG cost split was guesswork.
- Power factor drifted unnoticed, so the utility levied recurring PF penalty charges every billing cycle.
- Harmonics on compressor and drive circuits were completely invisible — a silent threat to critical machinery.
- Reports for management and audits were compiled by hand: late, incomplete, and impossible to verify.
02 · The solution — what Skylights Energy deployed
Skylights Energy installed the Switchology Energy Management System across both Harohalli plants — a fully self-hosted platform with no cloud dependency and no recurring subscription:
- 40+ digital energy meters connected over an RS485 Modbus backbone to Switchology gateways — one integrated device per plant with inbuilt storage and server, needing only power and a network point.
- EB vs DG source segregation with automatic logging of DG run-hours and units generated — every unit of diesel power is now accounted for.
- Live power quality visibility — kW, kVA, kVAR, power factor, voltage and current per phase, and harmonics (THD) on every monitored feeder.
- Temperature monitoring at critical points, logged alongside electrical parameters.
- Automated threshold alerts by email and dashboard for voltage fluctuation, PF drop, overload and harmonic limits — maintenance teams act before machines are damaged.
- Automated reports and timestamped CSV export — weekly and monthly reports delivered on time, with accurate, audit-ready data on demand.
- IEEE 519-2014 harmonic compliance analysis — continuous voltage and current THD tracking with individual harmonic order breakdown (5th, 7th, 11th, 13th) and automatic 6k±1 source signature identification for VFD, rectifier and drive-based loads.
03 · Before vs after
| Before | After |
|---|---|
| Manual meter reading and log-sheet entry | Automatic logging from 40+ meters — continuous, accurate, tamper-free data |
| No idea how long the DG ran or what it cost | DG run-hours and units tracked automatically; EB vs DG split known daily |
| PF drifted low → penalty on every bill | PF tracked live with alerts — penalties eliminated from the bill |
| Shutdowns with no explanation | Fluctuation alerts and per-feeder data pinpoint root cause immediately |
| Harmonics invisible — silent damage to machines | THD monitored per feeder with limit alerts — machinery safeguarded |
| Reports late, assembled by hand | Weekly/monthly reports on time; audit data exported in one click |
04 · Measured outcomes
- 9–14% — reduction in monthly energy cost; energy waste identified per feeder within the first weeks.
- ₹15–25K / month — recurring PF penalty charges eliminated across plant feeders.
- 100% — DG accounting: diesel generation reconciled against run-hours for the first time.
- 0 cloud fees — self-hosted platform: one-time cost, use forever, zero subscription.
On top of the numbers:
- Machinery safeguarded — fluctuation and harmonic alerts let the team act before equipment damage, protecting compressors and drives.
- Audit-ready data — accurate, timestamped records available on demand for energy audits and management review.
- Both plants running smoothly — stable operations with full visibility across all critical assets.
05 · Technical proof — IEEE 519-2014 harmonic analysis
Actual analytical output from the deployed gateway — not marketing, not simulated.
In December 2025, our Switchology gateway at Dairy Day Unit 256B produced a full 72-hour IEEE 519-2014 harmonic compliance report — sampled continuously across all three phases, with automatic source signature identification. This is the standard, on-demand output any Switchology deployment delivers.
Device SKYGW0.5GBR_V1 · 72 hrs continuous · 1-min sampling · 98% signature match
| Parameter | Measured (avg) | IEEE limit | Peak | Status |
|---|---|---|---|---|
| Voltage THD | 3.96% | 5.0% | 5.67% | ✓ Pass |
| Current THD | 11.83% | 20.0% | 31.00% | ⚠ Marginal |
| 5th Harmonic (I) | 8.27% | 7.0% | 17.50% | ✗ Exceeds |
| 7th Harmonic (I) | 4.48% | 5.0% | 15.80% | ✗ Edge |
| 11th Harmonic (I) | 5.02% | 3.0% | 26.10% | ● Critical |
| 13th Harmonic (I) | 1.33% | 2.0% | 14.10% | ✓ Pass |
The measured harmonic pattern precisely matches the theoretical signature of unfiltered 6-pulse diode rectifier VFDs — exactly the class of drive Dairy Day uses for IQF freezing, chilling and cold-room compressors. The gateway also computed a transformer K-factor of 1.28–1.38, quantifying real thermal stress and predicting insulation service-life reduction under continuous peak-load operation. This depth of analysis is impossible without granular per-phase, per-harmonic-order data captured every minute — precisely what Switchology delivers as the standard output of the deployment.
Load profile — when the problems peak
Averages hide the truth. The gateway sliced the 72-hour window into four load conditions and pinpointed exactly when harmonic distortion crosses IEEE limits:
| Load condition | Time period | Current THD | 11th harmonic | Frequency |
|---|---|---|---|---|
| Off-Peak | 05:00–07:00 | 7.2–9.1% | 1.5–2.8% | 12% of time |
| Normal Operation | 07:00–18:00 | 9.5–12.3% | 4.2–5.1% | 43% of time |
| Peak Load | 18:00–22:30 | 13.5–19.2% | 6.3–8.5% | 31% of time |
| High Peak (Critical) | 22:30–05:00 | 16.8–31.0% | 8.9–26.1% | 14% of time |
The gateway identified nocturnal chilling and freezing cycles (22:30–05:00) as the primary distortion driver — peak current THD reaches 31%, and 11th harmonic peaks at 26.10% (nearly 9× the IEEE limit). This is actionable intelligence: the system tells you when to shift loads, when to run DG, and when to intervene.
Equipment risk — quantified, not guessed
Beyond measurement, the gateway produced predictive equipment risk analysis using IEEE C57.91 thermal aging models — translating harmonic stress into concrete equipment impact:
- 15–22 °C rise — transformer temperature rise above nameplate during peak-load cycles.
- 25–35% — insulation service-life reduction predicted per IEEE C57.91 model.
- 3–5 yr impact — estimated transformer service life reduction under continuous operation.
This is what separates monitoring from advisory intelligence. Switchology doesn't just report the numbers — it converts them into equipment failure risk, so maintenance is planned, not reactionary.
06 · Return on investment
| Investment model | One-time hardware cost per plant — zero subscription, zero cloud fees, zero licensing renewals |
|---|---|
| Payback period | Full return on investment within 8–14 months of commissioning |
| Recurring recovery | ₹15,000–₹25,000/month in eliminated PF penalty charges, plus 9–14% reduction in monthly energy cost from waste elimination |
| Year 2 onwards | Savings are 100% retained — every rupee saved beyond payback is pure operational margin, for the lifetime of the installation |
Because Switchology is self-hosted with no recurring cost, the system continues generating value indefinitely after the initial investment is recovered — the ROI compounds every year it runs.
The strongest proof
Dairy Day has ordered two more plants. After running Switchology across two plants, Dairy Day has requested installation at two additional plants with 40+ more meters. No testimonial is stronger than a customer doubling their deployment — companies do not expand a system that isn't delivering.
Switchology — a Skylights Energy product. One-time cost. No cloud. No subscription. Use forever.