Oscilloscope USES FAQ collection
1. How to measure dc voltage?
A: first, set the coupling mode to dc, adjust the vertical tap position to an appropriate value according to the approximate range, and then compare the displacement of the offset line and channel mark.
2. Is the range of the 220V power measured beyond the range of the screen?How to measure phase difference of three-phase power supply?
A: the maximum input peak-to-peak voltage of DS5000 series is 400V. According to the effective value conversion peak-to-peak value formula, 220V power supply exceeds 400V peak-to-peak value, and the range is beyond the screen range.When using oscilloscope to measure phase shift of three-phase power supply, the trigger source can be set as mains electricity, and A channel is used to measure a-b waveform first, and then store it as reference waveform, and then connect the probe to b-c, and then the phase shift can be measured.
3. What is confounding inhibition?
A: confusion refers to a condition in which the frequency of oscilloscope collection is less than 2 times the maximum frequency of the actual signal.Obfuscation suppression is specially designed to prevent obfuscation, which can identify the maximum frequency of signal and collect signal at 2 times the maximum frequency.
4. How to catch the aperiodic signal?
A: set the trigger level to the required value.(2) click the main control button SINGLE, and the machine begins to wait. If a certain signal reaches the set trigger level, that is, sample once and display on the screen.This feature makes it easy to capture accidental events, such as large bursts of burring: set the trigger level just above the normal signal level, and click the SINGLE button. When the burring occurs, the machine automatically triggers and records the waveform of a period of time before and after the trigger.Drag the trigger position marker line to get different length of negative delay trigger, easy to observe the waveform before the occurrence of burr.
5. How to observe the noise of low-voltage dc power supply?
A: connect the oscilloscope probe between channel A1 (or A2) and the measured point.(2) set the Trigger Source as A1 or A2 (it must be consistent with the actual measured signal input channel).3. Click A1 or A2 button and select the coupling mode as AC (AC) coupling.(4) adjust sampling rate and vertical sensitivity until satisfactory display.
6. What is the relationship between trigger and waveform acquisition?
A: according to different types of oscilloscopes, oscilloscopes have different acquisition methods, and the relationship between trigger and waveform acquisition is different.If it is the equivalent time sampling mode of sampling oscilloscope or real-time oscilloscope, the acquisition of a waveform needs to be triggered several times to complete.For the real-time sampling mode of real-time oscilloscope, if the waveform is triggered once, it will definitely be collected once. If the waveform is not triggered, it may be collected. This is the AUTO mode triggered.(there are three trigger modes. One is AUTO, which will refresh the waveform if it is not triggered, but the waveform will be unstable on the screen; the other is NORMAL, which will refresh only when triggered; the last is SINGLE, which will capture the waveform after the first trigger.)
7.After collecting the signal, the waveform of the signal does not appear in the picture. How to deal with it?
Answer: check the following steps: 1. Check whether the probe is normally connected to the signal connection line; 2.2. Check whether the signal connector is normally connected to BNC (channel connector);3. Check whether the probe is normally connected with the object to be measured;4. Check whether there is a signal generated for the object to be measured (the channel generated by the signal can be connected with the channel with the problem to determine the problem).5. Signal collection again.
8.What are the applications of burr/pulse width trigger?
A: burr/pulse width trigger generally has two typical applications. The first is the synchronization circuit behavior, such as using it to synchronize serial signals, or for very serious interference applications, can not trigger the correct synchronization signal with the edge, pulse width trigger is an option;Another is used to find the anomaly signals, such as narrow burr caused by interference or competition, because the exception is accidental, must use burr trigger to capture (another method is the peak detection method, but the peak detection method of probably restricted by its maximum sampling rate, at the same time, usually can see, can't measure).If the pulse width of the measured object is 50ns and there is no problem with the signal, that is to say, there is no signal distortion or narrower caused by interference, competition and other problems, the signal can be synchronized with the edge trigger without using burr trigger.