Digital multimeter current measurement diagram

　　First of all, the multimeter must have a range for measuring current. Then insert the test leads into the current measurement jack on the left, and then connect the multimeter to the line to be tested. If you don't know how much current there is, it is best to adjust the gear to a higher level. If it is not suitable, lower it to a lower gear to avoid burning the meter.

　　① Insert the red test lead into the "μ, mA, ℃" or lOA jack, and insert the black test lead into the "COM" jack.
　　② Set the function range switch to μA￣=, mA￣ or A current measurement position. The default setting is DC current measurement. If you want to perform AC measurement, press the SE-LECT blue key to select AC current measurement.
　　③When measuring current, the test leads should be connected in series in the circuit under test, and the red test lead should be close to the positive side of the power supply, otherwise "-" will appear on the LCD display (AC current test leads are not positive or negative).
　　④Read the measurement results from the LCD display. The value measured by UyouOE is the true effective value.

　　Measurement precautions: ① The correct jack, function range and range should be used when measuring. If the current cannot be estimated, the test should start from the higher range; ② When testing large currents, for safety reasons, each measurement time should be less than 10S. , the interval is greater than l5min; ③ When the test leads are plugged into the current jack, do not connect the test leads in parallel to any circuit, otherwise the fuse or even the multimeter itself may be blown.

Direct current measurement 
　　1. Turn off the circuit power supply 
　　2. Disconnect or desolder the circuit to connect the meter in series to the circuit 
　　3. Select the corresponding AC (A~), DC (A--) gear 
　　4. Insert the black test lead into COM socket, insert the red test lead into the 10 Amp socket (10A) or the 300 mA socket (300mA). Choosing which jack is mainly based on possible measurements. 
　　5. Connect the test leads in series to the disconnected circuit part. 
　　6. Turn on the circuit power 
　　. 7. Observe the reading and pay attention to the unit. 
　　Note: When measuring DC, if the test probe is connected reversely, "—" will appear. 

　　A common mistake 　　with input protection  is to place test leads in current jacks while trying to test voltage. Small value resistors in a digital multimeter can cause a short circuit in the voltage source. A large current flows through the digital multimeter. If the multimeter is not adequately protected, it will not only damage the meter and circuits, but also harm the operator. If it is a high-voltage circuit (480 volts or higher), it will cause a greater danger. 

　　Therefore, the digital multimeter should have a current input protection fuse of sufficient capacity. Meters without current input fuses cannot be used in high energy circuits (>240V ac). For digital multimeters that use fuses, the fuse should have a capacity large enough to eliminate high-energy faults. The voltage rating of the fuse should be greater than the maximum voltage you expect. For example, a 20A, 250V fuse in a multimeter cannot protect a 480V circuit when the multimeter is measuring it. A 20A, 600V fuse can protect the multimeter when measuring a 480V circuit. 

　　Current Test Accessories 
　　Sometimes, the current value you want to measure exceeds the range of the digital multimeter or the site conditions do not allow you to open the circuit and measure the current. Current clamps are very convenient when testing high currents (usually greater than 2A) and do not require high accuracy. A current clamp is placed around a wire to measure the current and convert it into a value that a digital meter can process. 

　　There are two basic types of current probes: current transformer types, used only for AC measurements. Hall effect probe for measuring AC or DC current.

　　Current converter type. Generally, 1 milliamp is used to represent 1 amp. A current value of 100 amps will become 100 milliamps, which can be safely measured with a digital multimeter. Connect the wires to the "mA" and "Com" jacks and turn the function selector knob to the AC mA position. 

　　Hall effect type probe. Use 1 millivolt to represent the AC or DC value of 1 amp. For example, 100 amps of AC current will be converted to 100 millivolts of AC voltage. Connect the test leads to the "V" and "Com" jacks. Turn the function selection knob to "V" or "mV". At this time, the multimeter uses 1 millivolt to represent 1 amp of current.

 
　　When making current measurements while disconnecting or desoldering a circuit, the power supply to the circuit to be tested must be disconnected. Small currents can also cause danger. 

　　Do not test voltage with test leads plugged into current holes. It may cause damage to the watch or endanger personal safety. 

　　Transformer-type current probe, like the Fluke 80i-400. The digital multimeter uses a 1mA display to represent the actual 1A signal. 

　　Fluke I-1010 Hall Effect Probe can test very high AC or DC currents. It converts current into voltage signal. 

　　A voltage display of 1mV represents an actual current of 1A.