SOLUTION

FAQ

Q

Press the experimental button without releasing it

A
1. Check if there is power on both ends of the experimental button while working. If there is no power, it may be due to the asynchronous and out of place contact of the moving contact or damage to the 4.7K trip resistor. 2. Check if the transformer is open or short circuited (normal resistance paper is 46-500), and if the IC and thyristor are damaged. The most common issue is that the R4 feedback resistor C3 triggers the capacitor 3.3UF/50V, which is damaged.
Q

Fault caused by relay not closing

A
1. Check the condition of the relay; Use a multimeter to set the resistance to 200K and check if the relay has a resistance of 48K~52K. If there is no resistance value displayed, it means that the relay coil is open circuited. If the resistance value is too low, it means that the relay coil is short circuited. 2. Check if there is power supply at both ends of the relay. The most common situation is that the 0.5A fuse R2 relay current limiting resistor 7.5K10W is damaged, and the moving contacts are not synchronized and not in place, which can also cause the relay to fail to close. 3. Check if there is a short circuit on the circuit board that generates residual current causing the thyristor to operate.
Q

The red light is not on

A
1. Check if the red light is broken (consistent with the green light detection method) 2. Check if there is an open circuit at both ends of the red light power supply and if the electronic components are abnormal. Most of the N-pole leads have virtual soldering; If the moving contact is not synchronized and not in place, it will also cause the red light to not light up.
Q

The green light is not on

A
1. Check if the green light is broken, use a multimeter diode to test both ends of the green light (if it doesn't light up, it's broken), pay attention to the positive and negative poles 2. Check if the green light is powered on, and use a multimeter diode to check if there is an open circuit at both the positive and negative ends; Are electronic components malfunctioning. A common issue is that there are problems with the coordination between the LED spring and the contact piece of the moving contact, which require adjustment.
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