Question: How do you measure the current running through an electrical circuit?
Answer: It’s complicated! But it doesn’t actually need to be difficult, time-consuming, and dangerous.
The list of reasons why your organization may need to detect and measure current, which is one of the most foundational electrical parameters, is long. If using a multimeter to get that job done, it’s necessary to physically break into the circuit so that the current flows through it – and you get the reading. Even with an ammeter – a specialist device designed purely for taking current measurements – it is still necessary to break the circuit open in order to insert the test probes. Either way, it’s a fiddly, time-consuming, difficult, and obviously dangerous task.
It’s why more and more organizations are adding clamp meters to their toolbox.
Until the impressive latest iterations of this innovative technology, electrical specialists may have turned away from clamp meters because physically breaking into the circuit gave a more accurate reading. But given the ever-escalating precision of clamp meter technology, coupled with the ease, speed, and greater safety of working using one of these devices with nonetheless high-current circuits, it might be time to put one in the shopping cart.
To the untrained eye, a clamp meter looks like a standard multimeter – with a notable difference. Sitting at the top of these slick modern devices is the reason for the name: the clamp. Resembling the pincers of a crab, and often referred to as tongs or jaws, the ingenious clamp allows users to accurately test current without needing to actually break into or switch off – or even touch – the circuit in question.
How does it all work? In simple terms, the clamp meter’s input detects the only 1/1000th of the actual current that is flowing through the conductor – so that if the display shows 10 amperes, the meter has in the real world actually only detected 10 milliamps. Therefore, even extremely large currents can be both safely and accurately tested with a clamp meter, as only a small amount of current ever actually goes into the device’s input.
Let’s run through the main components one by one:
1. The clamp
With a multimeter or ammeter, a circuit must be broken into to get a current reading. But simply by ‘clamping’ the copper coil-wrapped, ferrite iron claws around the conductor in question, the magnetic core which is generated by the electromagnetic principle causes ‘magnetic flux’ – and you simply read off the displayed current.
2. The trigger
This is how the user operates the clamp itself.
3. The input terminals
4. The display
Easily read the current measurements in all light settings.
5. The switches/buttons
Used to calibrate the device for the specifics of the current you seek to measure, for example selecting between AC and DC current.
If this inspired piece of technology sounds ingenious in its operations but super-simple to operate without adding downtime or even requiring highly specialized technicians to oversee the process, you’d be right. Bear in mind, however, that clamp meters differ in their designs in terms of accuracy, operating environment, multi-functions/features, and meter rating, so always consult with an industry expert to match your organization’s needs with the best and most cost-effective device for your toolbox.