Resources
Every guide here answers one question that comes up before a diesel generator set is ordered. The numbers are the ones used in real quotations: kVA and kW ratings at 0.8 power factor, 400/230 V at 50 Hz, prime and standby duty to ISO 8528-1. Nothing on this page is a catalogue extract – each article shows the calculation, the table and the conditions it applies to.
What this section covers
How kVA becomes kW at 0.8 power factor, why the largest motor sets the size of the set, and how much margin a load list really needs. Start with how to size a diesel generator.
Prime, standby and continuous ratings are three different machines at the same kVA figure. The difference shows up in the load factor, the hours per year and the price band. See prime vs standby power.
Sound level in dB(A), footprint in square metres, transport weight and where each enclosure belongs. Compare silent, containerised, trailer mounted and open frame sets.
What changes when the load is a data centre, a hospital, a hotel, a construction site or an oil and gas site – from redundancy to noise limits.
How to use a guide
| Fact | What to write | Why it changes the answer |
|---|---|---|
| Rating and duty | e.g. 500 kVA standby, or 400 kVA prime | Moves the build between power bands, roughly one band up per step |
| Voltage and frequency | e.g. 400/230 V, 50 Hz, three phase | 50 Hz runs at 1500 rpm, 60 Hz at 1800 rpm – different engine and alternator |
| Site conditions | e.g. 45 C ambient, sea level, coastal air | Derating above 40 C and the enclosure type both follow from this line |
The power ranges used in these examples are the same ones quoted on this site: 100 kVA, 200 kVA, 500 kVA, 1000 kVA and 2000 kVA. The full list is on the diesel generator sets page.
Questions
The sales engineering desk at KVA Grid writes them, and each article carries its own update date. Numbers are re-checked when a rating or a standard changes: for example the derating figures follow ISO 8528-1 and the ambient reference of 40 C, so a page written for a 45 C site keeps the same method but a different result. If a figure on this site disagrees with the datasheet that comes with your set, the datasheet and the factory test report win.
You can get to a shortlist. The calculation in the sizing guide takes about ten minutes with a load list, and it will tell you whether you are looking at 400 kVA or 800 kVA. What it cannot do is confirm the build: the alternator frame, the enclosure rating, the fuel autonomy in hours and the freight all need a written quotation, which is what the request a quote form is for.
Yes. The Arabic site mirrors each guide at the same address under /ar/, using the same numbers and units, with Arabic terminology from our own glossary rather than a machine translation. If you prefer to discuss a rating in Arabic, the WhatsApp number on the contact page is answered in Arabic, English or Chinese.
Because a diesel generator set is quoted against a configuration, not a sticker. The same 500 kVA standby requirement can be built as an open frame set or a containerised set with a 24-hour tank, and the delivered price in Dubai, Jeddah or Karachi differs by the freight and the duties. So every page gives the rating, the method and the lead time, and the price comes back in writing with the datasheet.
Latest
New guides are added here first, newest at the top. Each one links back to the power range or form factor page it belongs to, so you can move from the explanation to the specification in one click.
Send the load list, the site conditions and the destination port. The reply carries the rating, the configuration and the lead time in writing.
A sound-attenuated canopy typically removes 20 to 25 dB(A), adds 1.5 to 2 m of length and 10 to 20 per cent of transport weight. Compare the choice on the permitted sound level, the space and the access route.
Prime power carries a variable load for unlimited hours with a 10 per cent overload for one hour in twelve; standby power is declared for the duration of a mains failure with no overload allowance. A 500 kVA set is two different machines depending on the rating.
Convert the running load to kVA at 0.8 power factor, add the starting demand of the largest motor, then add 10 to 20 per cent margin. A 320 kW load with one 55 kW direct-on-line motor needs about 800 kVA.
