Electrical Current Unit Converter + Reference Table & Applications
If you're wiring up a linear actuator or piecing together a control circuit, you'll run into current ratings in several units—amps for the actuator's stall current, milliamps on relay datasheets, sometimes even microamps if you're dealing with signal circuits. Mixing these up isn't just an inconvenience; use the wrong value and you might blow a fuse, cook a wire, or damage components. This tool gives you fast, plain conversions between microamps, milliamps, amps, and kiloamps—plus concrete examples and design notes specifically for actuator work.
What Is Electrical Current?
Current is just the rate that charge moves through a wire. The standard unit is the ampere (A). Other units—microamps, milliamps, kiloamps—are simply multipliers for different levels of current. You’ll see all four on datasheets, depending on the part or circuit.
Simple Explanation
Think of current like water moving in a pipe. Voltage is your water pressure; current is the amount of water flowing each second. Microamps mean next to nothing in actuator work—barely a trickle. Kiloamps are industrial-scale, far beyond anything you'll wire by hand. Most actuator circuits sit right in the 1–10 amp range, which is enough to get work done but not so high you need special hardware or installation steps.
Electrical Current Unit Converter
This calculator is intended for education, concept evaluation, and preliminary design. Results are based on the equations and assumptions described on this page, but cannot account for every real-world load case, tolerance, material property, environmental condition, installation detail, safety factor, code, or regulatory requirement. Verify all inputs, assumptions, units, and results independently before selecting components or using the result in a real application. Safety-critical, structural, medical, lifting, transportation, or regulated applications must be reviewed by a qualified engineer.
🎥 Video — Electrical Current Unit Converter
How to Use This Calculator
No need to press buttons—the tool updates instantly as you type. Here's how you use it in a real setting:
- Enter your current value in the field. The starting value is 1, but you can type any positive or negative number, including decimal points.
- Select your source unit from the dropdown to match your measurement (µA, mA, A, or kA).
- See all four converted values below as soon as you enter a number or change the unit.
- Compare to component specs. If you're checking if a relay rated for 3,000 mA will work with an actuator that draws 5 A, this instantly tells you if you're in trouble.
Electrical Current Unit Formula
The math here is simple and reliable—every current unit is just a multiplier for the ampere. Convert any current to amps, then out to your target unit using a fixed factor for each:
Value in Amps = Input Value × Source Unit Factor
Output Value = Value in Amps ÷ Target Unit Factor
| Symbol | Variable | Factor (relative to Amps) |
|---|---|---|
| µA | Microamps | 0.000001 |
| mA | Milliamps | 0.001 |
| A | Amps (base unit) | 1 |
| kA | Kiloamps | 1000 |
Simple Example
Problem: You have a current reading of 1 A. Express it in all 4 units.
Step 1 — Convert to amps (base unit):
1 A × 1 (factor for A) = 1 A
Step 2 — Convert to each target unit:
Microamps: 1 ÷ 0.000001 = 1,000,000 µA
Milliamps: 1 ÷ 0.001 = 1,000 mA
Amps: 1 ÷ 1 = 1 A
Kiloamps: 1 ÷ 1000 = 0.001 kA
Practical meaning: 1 amp is pretty typical for small actuators and other common devices. If you see 1,000 mA on a wall adapter, that's exactly the same thing—just different labeling. Important to check units before plugging numbers into your calculations.
Engineering Applications
FIRGELLI Actuator Current Ratings
Expect actuator currents between 2 and 10 A at 12 V, depending on model, load, travel speed, and stall conditions. Be aware that unloaded actuators may draw less—sometimes about 0.5 A—but apply maximum load and current will rise significantly, into the 4–6 A range or more. When budgeting for wiring, connectors, relays, or fuses, always use stall current, not normal running current, because that's the situation that can stress your system.
Our actuator specs list current in amps (A), but you might see milliamps used by current sensors, datasheets, or some microcontroller feedback circuits. It’s smart to check both—the converter helps you verify. For example, a reading of 4,500 mA lines up with a datasheet value of 4.5 A. If you see readings much lower than expected, something in your wiring or measurement chain needs attention.
Stall Current — The Number You Can't Ignore
Stall current is almost always several times higher than running current—often 3–5 times, and it shows up when an actuator is blocked, at its travel limits, or in a mechanical jam. You might only see this for a split second before a breaker trips, but your wiring and fuse must handle it. If your actuator is rated for 5 A running, expect stall current up around 15–25 A. Wire and fuse size should always be chosen for this peak, or you'll end up replacing blown fuses or, worse, overheated wire insulation.
For actuator circuits with up to 20 A stall, 16 AWG wire works for short runs. For more current or longer distances, size up. Use a slow-blow fuse to tolerate stall surges, but if you size fuse and wire for just running current, you'll be fixing the same problems repeatedly.
Keeping High-Current and Low-Current Wiring Separate
Signal circuits—limit switches, sensors, feedback pots—usually draw 1–20 mA. These wires are more likely to be bothered by interference from actuator leads than by their own current draw. Always keep power and signal wiring separated by a couple inches, or run signal wires in shielded cables. This prevents EMI from strong currents (say, actuator leads at 8 A) from inducing noise and causing erratic readings. Basic enclosure layout—power one side, signals the other—prevents troubleshooting headaches down the road. Use twisted-pair cable if you're chasing signal noise problems.
If you run signal and actuator power wires together, don't be surprised when your readings are noisy or unreliable. Keep them apart or shield them from the start.
Advanced Example
Scenario: You're designing a system with 2 FIRGELLI actuators. Each draws 6.5 A running current and has a stall current of 22 A. Your current sensor outputs readings in milliamps. You need to verify fuse sizing and confirm your sensor readings make sense.
Step 1 — Convert running current to milliamps:
6.5 A × (1 ÷ 0.001) = 6,500 mA per actuator
Total for 2 actuators: 6,500 × 2 = 13,000 mA = 13 A
Step 2 — Convert stall current to milliamps:
22 A × (1 ÷ 0.001) = 22,000 mA per actuator
Total stall for 2 actuators (worst case, both stall simultaneously): 22,000 × 2 = 44,000 mA = 44 A
Step 3 — Express total stall current in kiloamps for panel specifications:
44 A × (1 ÷ 1000) = 0.044 kA
Step 4 — Design interpretation:
When both actuators are running at max load, you should see about 13,000 mA on your sensor. If not, check for voltage drop, under-sized wire, or loose connections. Fuse sizing must cover that worst-case 44 A stall—50 A slow-blow gives you a buffer. Run 6 AWG wire for up to 15 feet, or 8 AWG for shorter distances. If you try to run this system on 16 AWG (sized for average current), you risk serious overheating the moment you hit stall.
Frequently Asked Questions
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About the Author
Robbie Dickson — Chief Engineer & Founder, FIRGELLI Automations
Robbie Dickson brings over two decades of engineering expertise to FIRGELLI Automations. With a distinguished career at Rolls-Royce, BMW, and Ford, he has deep expertise in mechanical systems, actuator technology, and precision engineering.
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