What Size Generator Do I Need? Guide and Calculator
A generator that is too small trips under load, and one that is too large wastes fuel. Work through four numbers first.
Step 1: total running load
List everything that runs at the same time and add the power in kW. This is your running load.
Step 2: the largest motor
A large motor draws a surge when it starts, typically about six times full-load current for direct-on-line starts. The generator must ride through it. A soft starter lowers the surge.
Step 3: power factor and kVA
Generators are rated in kVA. Divide kW by the power factor (0.8 is a common value) to convert.
Generator size estimate
Motor starting current is typically about six times full-load current for direct-on-line starts. Use your starter's figure if it is lower.
Step 4: prime or standby, and heat
Prime units run for long hours as the main supply. Standby units cover outages. High ambient temperature reduces output, so Saudi summers matter: tell us the site and we allow for derating.
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Call us or send a quote request. Our team helps you choose the right machine and size before you commit.