Feature:1. Easy Calibration: This meter adopts exquisite SMT technology, so it has good consistency. It is equipped with current calibration potentiometer and zero adjustment potentiometer. If there is any error, you can calibrate it yourself.2. Simple and Safe Operation: The current sensor adopts a through hole design, and the wire directly passes through the hole. The current measurement can be realized without damage or changing the original current circuit.3. Isolated Design: Because the current sensor is completely electrically isolated from the measured wire, this meter can measure the current of the positive pole, negative pole of the power supply, a certain line at will. The voltage withstand value between the measured wire is up to 2KV.4. Forward and Reverse Current: Ammeter can measure the forward and reverse current of the line, display the positive current in the forward direction (the decimal point of the ammeter is always on or off), and display the negative current in the reverse direction (the decimal point of the ammeter flashes slowly).5. Wide Applications: Equipped with two wires to facilitate access to solar energy system, car, battery car and motorcycle lines, timely grasp the charging and discharging status of battery, and can also be used for other purposes.Specification:Item Type: Digital AmmeterMaterial: ABSCurrent Range: 50A Test Range (V):+/-0.0-50A, Resolution (A): 0.1APower Supply Voltage: 4-30V (Wide Range) Note: The Maximum Input Voltage Cannot Exceed 30V, Otherwise There is a Risk of BurningDisplay Mode: 0.52in LED, RedExternal Dimension: Approx. 54 x 30 x 21mm / 2.13 x 1.18 x 0.83inInstallation Opening: Approx. 47.2 x 27.3mm / 1.86 x 1.07inMeasurement Rate: 500mS/TimeMeasurement Accuracy: 1% ( 2 Words)Power Supply End Lead: Approx. 150mm / 5.91inTransformer Lead: Approx.150mm / 5.91inMinimum Supply Voltage: +4.0VMaximum Supply Voltage: +30VWorking Temperature: - 10-+65Working Humidity: 10-80% (No Condensation)Working Pressure: 80-106kPaExposure To The Sun: Direct exposure is not allowedCalibration Method: The relative error between the instrument and the instrument, or the error caused by the aging of components or environmental temperature change after long term use, can be calibrated by the following methods. In order to obtain more accurate measurement, it is recommended to preheat for more than 5 minutes before calibration.Current Calibration: Under the condition that there is no current flowing, use a slotted screwdriver to adjust the zero potentiometer behind the mutual inductor until the decimal point of the ammeter flashes quickly as the best point; Constant light or no light indicates that the zero point is positive, and slow flashing indicates that the zero point is negative.Then, under the condition of loading half of the actual current value to be measured, adjust the amplitude modulation potentiometer on the side of the transformer until it is consistent with the standard table.If the test accuracy is very high, the above two steps can be repeated to obtain higher accuracy..Package List:1 xDigital Ammeter