Clamp Meter Application Scenarios, Advantages and Uses
In the daily work of master electricians, clamp meter is a "rate of appearance" is very high electrical testing tools. It is the detection of the operation of the AC circuit current is most commonly used in a kind of instrumentation, because the measurement does not need to disconnect the circuit being measured, so it is very convenient to use. So, do you know how to choose the best clamp meter for you?
Advantages and Uses of Clamp Meter
Most clamp-on meters have the first-line electrical diagnostic testing capabilities of a digital multimeter (DMM), or they can be connected to a circuit and use test leads to measure voltage, current, frequency, capacitance, temperature, and resistance (as well as continuously test the circuit to see if there are any faults or deficiencies in the circuit, etc.). It also has an extra set of specialised spring-loaded jaws of various sizes that can be clamped around wires or busbars for non-intrusive current measurements.
Clamp meters typically measure common AC and DC currents. Clamp meters that measure AC are primarily used for public power, while those that measure DC are primarily used for measuring AC to DC conversion motors in industry, as well as measuring battery DC power supplies, and measuring DC power supplies used in electric vehicle systems and measuring DC batteries for solar arrays. Whilst multimeters can be used to obtain contact amperage readings up to 10A using test leads, clamp meters can provide safer, non-destructive current readings in ranges up to 3000A.
There are some clamp-on meters that are single-purpose, pure ammeters, trading other features for smaller jaws, higher resolution readings, higher sensitivity and an overall compact, pocket-sized design. Other ammeters will also have a "flex-clip" flexible ring instead of a jaw. The long, flexible ring can be manually wrapped around crowded cables in cabinets that may be difficult to access with rigid jaws.
There are also a number of high quality clamp meters that offer better accuracy for more challenging jobs, and a "true RMS" (root mean square) clamp allows for more accurate equivalent DC RMS measurements when the current waveform is sinusoidal or non-sinusoidal. When wires are bundled together, the inductive coupling between the wires due to current can cause stray (or "ghost") voltages, resulting in inaccurate readings, which can be eliminated by using the "LoZ" mode. If inverter driven devices (VFDs) are used in industrial sites, the low-pass filtering mode "Lo-Pass" can be used to improve measurement accuracy. Some models of clamp-on meters also use an in-built pointing non-contact infrared thermometer to measure temperature (spot temperature gun). Some also use dual thermocouple inputs to calculate the temperature difference ("Δ-T"), which is essential for HVAC/R engineering work.
Clamp meter application scenarios
Firstly, check the overvoltage category designation ("CAT" for short) of the clamp meter to see where it can be used; CAT II meters can be used for plug-in equipment and appliances, while CAT III meters can be used for fixed wiring in buildings. The most robust category, CAT IV, is used by utility companies for service panels and low voltage outdoor wiring. For safety reasons, potential job requirements should always be considered and the best CAT nominal rating selected. Clamp meters can measure current loads on circuit wiring and equipment, including motors, pumps, lighting, sensors and switches. They are found everywhere from DIY toolboxes to industrial maintenance tool carts.
