Maximum Demand Calculator Site

To take control of this, you need a . What is Maximum Demand? Maximum Demand is the highest average load (usually measured over 15, 30, or 60-minute intervals) that a system draws during a billing period.

In the world of electrical engineering and facility management, Maximum Demand (MD) is a critical metric. It isn't just about keeping the lights on; it directly impacts your capital expenditure (cable/transformer sizing) and operational expenditure (electricity bills).

Apply the factors from the table above.

Disclaimer: This guide provides estimation methods. Always consult a licensed electrical engineer for final design and safety compliance.

[ MD = (Load_1 \times DF_1) + (Load_2 \times DF_2) + ... + (Load_n \times DF_n) ] maximum demand calculator

Why average? A motor starting up might draw 600A for 2 seconds, but that doesn't melt the cables. The 15-minute average is what heats the transformer. Why does it matter? Utilities size their transformers for your MD. If you have a 5-minute spike once a month, you are paying for infrastructure you use 0.01% of the time. You cannot simply add up the nameplate ratings of all breakers. That is Connected Load , not Maximum Demand. Diversity saves you.

Where is the Demand Factor (or Diversity Factor). Standard Demand Factors (Reference Guide) | Load Type | Typical Demand Factor | Notes | | :--- | :--- | :--- | | Lighting (Office) | 0.75 – 0.90 | Fluorescent/LED | | Lighting (Warehouse) | 0.95 – 1.00 | High bay, always on | | General Power Outlets | 0.10 – 0.50 | Varies heavily by occupancy | | HVAC (Cooling) | 1.00 | Worst-case summer day | | HVAC (Heating) | 0.80 – 1.00 | Electric heat is high demand | | Lifts / Elevators | 0.40 – 0.60 | Largest motor only | | Motors (Continuous) | 1.00 | Pumps, compressors | | Motors (Intermittent) | 0.40 – 0.60 | Conveyors, cranes | | Kitchen Equipment | 0.40 – 0.70 | Not all used at once | The "Pro" Calculator Tool (Manual Method) If you don't have a power analyzer, use this systematic approach to estimate your MD. To take control of this, you need a

Grab your last 12 utility bills. Find the highest "Demand" value. Compare it to the sum of your connected load. You will likely find you are paying for capacity you rarely use.