Five points to note when using an oscilloscope

    1. For the safety of the instrument operator and the instrument, the instrument should work normally within the safe range to ensure accurate waveform measurement, reliable data, and reduce external noise interference; the general oscilloscope can adjust the brightness and focus knobs to minimize the diameter of the light spot to make the waveform clear and reduce the test error; do not let the light spot stay at one point, otherwise the electron beam bombarding one point will form a dark spot on the fluorescent screen and damage the fluorescent screen.

　　2. Measurement system - such as oscilloscope, signal source; printer, computer and other equipment. The grounding wire of the electronic equipment under test - such as instruments, electronic components, circuit boards, power supply of the equipment under test, etc. must be connected to the public ground (earth).

　　3. When the TDS200/TDS1000/TDS2000 series digital oscilloscope is used with a probe, it can only measure the waveform of the signal (the measured signal - the signal ground is the earth, and the signal end output amplitude is less than 300V CAT II). It is absolutely not allowed to measure the floating ground signal of the AC220V mains power or the electronic equipment that cannot be isolated from the AC220V mains power. (The hot ground cannot be connected to the earth, otherwise it will cause damage to the instrument, such as testing an induction cooker.)

　　4. The housing of a general oscilloscope, the metal outer ring of the signal input BNC socket, the probe ground wire, and the AC220V power socket ground wire are all connected. If the instrument is not connected to the ground wire when in use, and the probe is used directly to measure the floating signal, the instrument will have a potential difference relative to the ground; the voltage value is equal to the potential difference between the point where the probe ground wire contacts the device under test and the ground. This will bring serious safety hazards to the instrument operator, the oscilloscope, and the electronic equipment under test.

　　5. If the user needs to measure switching power supplies (switching power supply primary, control circuit), UPS (uninterruptible power supply), electronic rectifiers, energy-saving lamps, inverters and other types of products or other electronic equipment that cannot be isolated from AC220V mains power for floating signal testing, the DP100 high-voltage isolation differential probe must be used.