Main performance of electronic counter

Source: electronic counter, electronic meter, Wuxi Huajian Electronic Instrument Research Institute

1, test function

The test function of the electronic counter includes measuring frequency, period, frequency ratio, time interval, accumulating count and self - correction.

2, measuring range

The effective measurement range of the electronic counter is different from the function of the measurement, and the measurement range is different. The upper and lower limit of frequency is the lowest and the lowest value of the periodic time unit.

3, input characteristics

Under normal circumstances, when the instrument has 2 to 3 input channels, the need to give the characteristics of each channel, mainly:

1) input sensitivity: the minimum voltage required for a normal operation of the instrument.

2) the input coupling mode: there are two kinds of coupling of AC and DC. AC coupling, the signal to be measured by an isolating capacitor input; DC coupling measured signal is directly input in low frequency and pulse signal input to the occasion with this coupling

3) input impedance: including input resistance and input capacitance, and have high impedance such as 1 M pF //25 and low impedance for example 50). The former is used to reduce the load of the signal source, and the latter is used to meet the matching requirements.

4) the maximum input voltage: the maximum input voltage. Beyond the maximum input voltage, the instrument can not guarantee the normal work, and even will be damaged.

4, measurement accuracy

The measuring accuracy of the measurement error to said, is mainly decided by the counting error and time error. Time base error by the degree of the stability of the crystal oscillator, electronic counter usually standard frequency crystal oscillator is given and its frequency stability; counting error mainly refers to the quantization error.

5, gate time and time scale

The standard time signal provided by the instrument internal standard time signal includes the gate time signal and the time signal.

6, output

Here refers to the instrument can output the standard time frequency) the type of signal, the output data of the encoding mode and the output level, etc.. Electronic counter