When conducting the inspection, there are no connecting wires between the instrument and external devices. The inspection steps are as follows:

1. It is prohibited to connect voltage and current to the output terminals of voltage and current;

2. Check whether the appearance of the instrument is damaged, lift the instrument, whether there is any abnormal sound inside the instrument, and whether the knobs, wiring terminals, and screws of the instrument are loose;

3. Turn the current and voltage adjustment knobs counterclockwise to the minimum;

4. Before using the instrument, the reliability of the power supply should be checked, and the power voltage should be measured with a multimeter to avoid damage to the instrument due to the working voltage exceeding the working range;

5. Connect the instrument to a qualified AC power source, turn on the main power switch, and there will be a thermal warning sound for about 15 seconds. After the sound is cleared, the instrument can be used.

　　

The above are the checks that need to be done when using the comprehensive drug stability test box.