Demand power, installed (connected) power × simultaneity factor Demand is found using the formula: since not all loads operate simultaneously, demand is generally lower than the installed power. The demand current is calculated as I = P/(√3·U·cosφ). This value is used in the selection of the main circuit breaker, meter, cable, and transformer.

Demand power = Installed power × simultaneity · I = P / (√3·U·cosφ)
Example calculation: 500 kW installed power, simultaneity 0.7 → demand power 350 kW; 400 V, cosφ 0.9 → demand current ≈ 561 A. The main power supply is selected according to this value.

Demand Force & Simultaneity

Calculate the plant's demand power and approximate demand current by multiplying your installed (connected) power by the simultaneity factor (prior information on main supply, meter, and transformer sizing).

Demand power
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Demand flow
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Notes: Demand power = Installed power × simultaneity factor; I = P/(√3·U·cosφ). The simultaneity factor varies depending on the facility type. (Residential, office, industrial use differs) and must be verified with the actual load profile. This is an estimate; the selection of the main circuit breaker, cable, and transformer will be finalized through engineering calculations.
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How is it calculated?

  1. Enter the installed (connected) power (kW).
  2. Enter the concurrency/demand factor (0.4–0.9 depending on the facility).
  3. Press Calculate with voltage and cosφ.

Frequently Asked Questions

What is the simultaneity factor?
It is a coefficient that represents the percentage of connected loads that are not operating simultaneously, and it varies according to the type of facility (residential, office, industrial).
Why is demand power important?
The main circuit breaker, meter, cable, and transformer are sized according to this value; choosing based on installed power will result in unnecessary costs.
How to find the demand flow?
Power of demand is calculated using the formula I = P/(√3·U·cosφ).

Related tools and services

This tool and its content are for general informational purposes only; they do not constitute a binding inspection/declaration of conformity. Definitive results will be determined through on-site inspection in accordance with relevant legislation and standards. Get a quote →