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Digital ammeter is a commonly used measuring instrument, which converts the measured current value into digital output and is expressed in digital form by analog-to-digital converter, and is widely used in many fields. What should users pay attention to in the process of using digital ammeter? The following Xiaobian will specifically introduce the precautions for the use of digital display ammeter, hoping to help you.

 

Digital display ammeter introduction

Digital display ammeter is divided into single-phase digital display ammeter and three-phase digital display ammeter, the table has the functions of transmission, LED(or LCD) display and digital interface, through the AC sampling of various parameters in the power grid, the measurement results are displayed in digital form. Data processing by CPU. The three-phase (or single-phase) current, voltage, power, power factor, frequency and other electrical parameters are directly displayed by the LED(or liquid crystal), while the output of 0 ~ 5V, 0 ~ 20mA or 4 ~ 20mA corresponding analog electricity, connected with the remote device rtu; And with RS--232 or 485 interface.

 

Digital display ammeter use precautions

1, before use, the instrument needs to be powered for 15 minutes.

2, pay attention to prevent vibration and impact, do not use in places with excess dust and excess harmful gases.

3, the input wire should not be too long, if the measured signal input is long, please try the twisted pair shielded wire.

4, if the signal is accompanied by high-frequency interference, the low-frequency filter should be tried online.

5, long time storage unused, please power once every three months for not less than 4 hours.

6, long-term storage should avoid direct light, should be stored in the ambient temperature -25°C~55°C.

7, if the instrument does not show, should first check the auxiliary power supply, the voltage is within the range.

8. If the display is abnormal, check whether the input signal is normal and whether the signal terminal is tightened.

9, unless the PT has enough power, you can not use the PT signal as an auxiliary power at the same time to ensure the normal operation of the instrument.

10. The screw of the current terminal in the CT circuit must be tightened to ensure reliable contact of the incoming/outgoing wires to avoid failure.

11, If you want to verify the instrument, the calibration instrument should be better than 0.1, in order to ensure the accuracy of the calibration.