The 5 main uses of clamp ammeters
Usually, when measuring current with a regular ammeter, it is necessary to connect the ammeter in series to the circuit for measurement after powering off the circuit. This is very troublesome, and sometimes normal operating circuits do not allow this. At this point, using a clamp ammeter becomes much more convenient. The clamp ammeter can measure current without cutting off the circuit, as long as the wire being measured is clamped in the clamp. However, clamp gauges generally have low accuracy, typically ranging from 2.5 to 5 levels, and are typically only used when the voltage of the tested circuit does not exceed 500V.
There are many types and styles of clamp ammeters. For example, the T-301 clamp ammeter can only be used to measure AC current, while the T-302 clamp ammeter can measure both AC current and AC voltage. The MG24 pocket clamp ammeter can also measure both AC current and AC voltage; There are also clamp type ammeters for both AC and DC, such as MG21 and MG22 models. When conducting measurements, different forms of clamp ammeters should be selected based on the different objects being measured. If only measuring AC current, T-301 clamp ammeter can be selected. If using other forms of clamp ammeters, the conversion switch should be turned to the desired position according to the measured object.
According to the display method of readings, clamp ammeters can be divided into two categories: pointer type and digital type; From the perspective of circuit voltage, there are low-voltage clamp gauges and high-voltage clamp gauges; From a functional perspective, clamp current meters include ordinary AC clamp meters, AC/DC dual-purpose clamp meters, leakage current clamp meters, clamp meters with multimeters, etc. The appearance of clamp watches varies greatly,
A regular clamp meter can only be used to measure AC current and cannot measure other electrical parameters. The clamp meter with a multimeter function is an addition to the clamp meter, and its usage method is the same as that of a multimeter.
The working principle of a digital clamp watch is basically the same as that of a pointer clamp watch. The difference is that a LCD display screen is used to display numerical results. The biggest feature is that there is no reading error, the ability to remember measurement results, and the ability to measure first and then read.
Next, let's take a look at the structure and working principle of a clamp ammeter
Structure of magneto electric clamp ammeter
The magneto electric clamp ammeter mainly consists of a special current transformer, a rectified magneto electric ammeter, and internal circuits. The common models are T301 and T302. The T301 clamp type ammeter can only measure AC current, while the T302 type can measure both AC current and AC voltage. There are also AC and DC dual-purpose pocket clamp ammeters, such as MG20, MG26, MG36 and other models. The appearance of the T301 clamp shaped watch is shown in Figure 7-6. Its accuracy is level 2.5, and the current range is: 10 A, 50 A, 250 A, 1000 A.
