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On this section of our website, you will find engineering-grade formulas and calculators that allow you to perform your technical calculations quickly and accurately.

Electrical Formulas Calculator (Volt • Watt • Amp • Ohm • kVA)

This tool calculates core electrical formulas for DC / single-phase / three-phase systems. Any values you leave blank will be calculated automatically (when possible).

Ohm’s Law & DC Basics

V = I·R—
I = V/R—
R = V/I—
P = V·I—
P = I²·R—
P = V²/R—
Tips: Enter at least two values (e.g., V and R) and the calculator derives the remaining ones. Negative/zero values are generally not meaningful in most physical cases.

Energy (Wh / kWh) & Time

Total Time (hours)—
Energy (Wh)—
Energy (kWh)—
Formula: E(Wh) = P(W) × t(h) and E(kWh) = E(Wh)/1000.

AC Single-Phase (kW, kVA, Current)

kW = (V·I·cosφ)/1000—
kVA = (V·I)/1000—
kVAR = kVA·sinφ—
Current (A) = (kW·1000)/(V·cosφ)—
Note: For resistive loads (e.g., heaters) cosφ is typically close to 1. For motors/inverters, cosφ varies by application.

AC Three-Phase (kW, kVA, Current)

kW = (√3·V·I·cosφ)/1000—
kVA = (√3·V·I)/1000—
kVAR = kVA·sinφ—
Current (A) = (kW·1000)/(√3·V·cosφ)—
In three-phase systems, apparent power (kVA) and line current are critical parameters for supply sizing and cable/breaker selection.

Heater Resistance (From Power)

Estimated Current (A)—
Equivalent Resistance (Ω)—
Formula Note—
For single-phase/DC: R = V²/P, I = P/V. For a balanced three-phase resistive load, current and phase resistance depend on star/delta connection.
Optional extensions: cable size selection (current density), fuse/breaker selection, voltage drop, plus “system power” sizing including heat losses and efficiency (η).

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Band / Nozzle Heater Power Calculator
Metric based calculator (mm & W/cm²). Inch input is also supported. Standard band opening is 5% (editable). Hole areas are subtracted. Safety factor is editable with default 1.05. Currents are calculated as single-phase line current for 230V and 380V.

1) Watt Density & Standards

2) Geometry & Holes

Results

Net Heated Area—
Final Heater Power—
Rated Power (50W rounded)—
Current @ 230V—
Current @ 380V—
Electrical (single-phase line current): I = P / V

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ApplicationBand Opening (%)Notes
Standard ceramic band4–6%Most common
Mica band heater3–5%Tighter fit
Nozzle heater0–2%Often near full wrap
Custom clamp design6–10%Large terminals

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Ceramic / Mica Plate Heater Calculator
Computes net heated area (cm²) for plate heaters (square, rectangle, oval, half-moon, round, round ring, oval ring), subtracts hole areas, and outputs finished power using W/cm² + safety factor.

1) Material, Watt Density Guide & Settings

Power formula: P(W) = A_net(cm²) × W/cm² × SF

2) Shape, Geometry & Holes

Holes are subtracted as: A_holes = N × π × (d/2)². If multiple hole sizes exist, use an average diameter and total count.

Results

Shape Area A_shape—
Hole Area A_holes—
Net Area A_net—
Finished Power P—
Rated Power (50W rounded)—
Current @ 230V (A)—
Current @ 380V (A)—
Liquid Tank Heating Calculator (Power & Time)
Select a liquid to auto-load density and specific heat, then enter volume and temperatures. The calculator returns required energy, required heater power, or required heating time.
1) Liquid Properties
If a value is missing, choose Custom and enter density/cp manually. Conversion: 1 kcal = 4186.8 J.
2) Temperature & Heater Inputs
If you enter time, the calculator outputs required power. If you enter power, it outputs required time.
Results
ΔT (°C)—
Mass (kg)—
cₚ (J/kg·K)—
Energy Q (kWh)—
Required Power (kW) for entered time—
Required Time (h) for entered power—

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Gas / Air Heating Calculator (Flow-Based)
Calculates required heating power for gases using volumetric flow rate and temperature rise. Select a gas to load density (kg/m³) and specific heat (kcal/kg·°C). Outputs: mass flow, energy rate, required power (kW), and required flow (m³/h).

1) Gas Properties & Flow

If density or cₚ is missing, choose Custom and enter values manually. Conversion used: 1 kcal = 4186.8 J.

2) Temperature & Target

You can use either:
• T_in and T_out to define ΔT, or
• directly enter Target ΔT.
If you enter available power, the calculator also returns the maximum achievable ΔT at that flow.

Results

ΔT (°C)—
Volumetric Flow (m³/h)—
Mass Flow ṁ (kg/s)—
cₚ (J/kg·K)—
Heat Rate Q̇ (kW) (ideal)—
Required Heater Power (kW) (with η)—
Required Flow (m³/h) for entered Power & ΔT—
Max ΔT (°C) for entered Power & Flow—
Core equations:
ṁ = ρ · Q̇_v (Q̇_v in m³/s)
Q̇ = ṁ · cₚ · ΔT
P_required = Q̇ / η

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