1. What is an Enclosure Heater Size Calculator?

Definition: This calculator estimates the required heater wattage for electrical enclosures based on surface area, desired temperature rise, and a material factor.

Purpose: It helps engineers and technicians properly size heaters to prevent condensation and maintain optimal operating temperatures in enclosures.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( W \) — Heater size (Watts)
• \( SA \) — Surface area of enclosure (square feet)
• \( TR \) — Desired temperature rise (°F above ambient)
• \( F \) — Material factor (typically 0.25 for metal enclosures)

Explanation: The surface area multiplied by temperature rise gives the base heat requirement, which is then adjusted by the material factor.

3. Importance of Proper Heater Sizing

Details: Correct heater sizing ensures reliable operation of electrical components by preventing condensation while avoiding excessive energy use or overheating.

4. Using the Calculator

Tips: Enter the enclosure surface area in sq ft, desired temperature rise in °F, and material factor (default 0.25 for metal). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the typical material factor value?
A: 0.25 for metal enclosures, 0.15 for plastic, and 0.1 for well-insulated enclosures.

Q2: How do I calculate surface area?
A: For rectangular enclosures: 2*(length*width + length*height + width*height) in square feet.

Q3: What temperature rise should I use?
A: Typically 10-20°F above ambient to prevent condensation, but check component requirements.

Q4: Should I round up the heater size?
A: Yes, always round up to the next available standard heater wattage.

Q5: Does this account for heat loss from ventilation?
A: No, for ventilated enclosures, increase the calculated wattage by 10-20%.