Generator noise is usually quoted in dB(A) at 7 metres. A “silent” canopied 100 kVA set around 70–72 dB(A) is still loud next to a bedroom window. Distance, barriers, orientation and load all change the experience. Specify acoustic targets early for estates, lodges and urban plant rooms.
Why this decision matters
Generator noise is usually quoted in dB(A) at 7 metres. A “silent” canopied 100 kVA set around 70–72 dB(A) is still loud next to a bedroom window. Distance, barriers, orientation and load all change the experience. Specify acoustic targets early for estates, lodges and urban plant rooms. Buyers who skip structured sizing or compliance checks pay twice: once for the wrong unit, and again for downtime, fuel waste or a failed insurance claim.
AGP Generators engineers treat every enquiry as a load and site problem first, a product second. The notes below are the same framework we use on commercial RFQs across South Africa and SADC.
Practical method
Step-by-step
Start with a written load list: running watts, starting watts, duty cycle and which loads are truly critical. Convert watts to kVA using power factor (0.8 is the commercial default unless you know otherwise).
Apply site factors next — altitude derate, ambient temperature, fuel quality and whether the set will see prime hours or true standby. Only then shortlist engine brands and canopy types.
Validate with our Sizing calculator and a specialist review before you issue a purchase order. Catalogue pages for the 100 kVA Perkins silent and 30 kVA three-phase silent show real price bands excl. VAT to sanity-check budgets.
- Record running and starting loads separately for motors and compressors.
- Separate essential vs shedable circuits so you do not oversize the set.
- Confirm phase (single vs three) against the DB and utility supply.
- Document who owns installation, CoC and first service.
Reference data
Use the table as an indicative planning aid, not a substitute for a site assessment. Prices and fuel figures move with diesel wholesale rates and exchange rates — we re-verify commercial quotes at order stage. Last updated 2026-07-01.
Common mistakes
Copying the kVA of a failed set without measuring today’s load. Ignoring motor starting. Buying open-frame units for estate boundaries. Skipping changeover and earthing design. Assuming “silent” means inaudible indoors.
How AGP helps
We size, supply, install and maintain diesel and petrol generators from 2.2 kVA to 1000+ kVA. Request a quote with your load list, or call +27 41 007 0618. For hybrid and long-hour sites, ask about diesel-solar controllers that keep engines in an efficient band.
Data table
Typical sound pressure (indicative at 7 m)
| Set type | dB(A) @ 7 m | Perception |
|---|---|---|
| Open frame industrial | 90–98 | Very loud |
| Standard canopy | 75–82 | Loud conversation |
| Silent canopy mid kVA | 68–74 | Busy street |
| Residential super-silent | 60–66 | Normal speech |
Figures are indicative. Last updated 1 July 2026.
Frequently asked questions
Is dB(A) at 1 m or 7 m?
Industrial gensets commonly quote 7 m — compare like with like.
Does load change noise?
Yes; higher load and certain RPM points are louder.
Estate limits?
Check body corporate rules before you buy an open set.
Can I box an open set later?
Purpose-built canopies and airflow matter — DIY boxes overheat engines.
Hospital specs?
Often need lower dB and vibration isolation — flag it in the RFQ.
Related tools: Sizing calculator · All insights
Related sizes, categories and services: 100 kVA generators, 30 kVA generators and petrol generators.
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