A method for measuring the leakage of electric soldering iron using a digital multimeter
1. Using a digital multimeter to measure leakage voltage
Measure the leakage voltage of the soldering iron using the AC voltage range of a digital multimeter.
When measuring the leakage voltage of an electric soldering iron using the AC voltage range of a digital multimeter, the digital multimeter should be set to the AC voltage range first (the figure uses an automatic range changing digital multimeter), and then use one probe to contact the soldering iron tip and the other probe to contact the ground wire (or ground). At this time, the AC voltage displayed on the multimeter is the leakage voltage. If the soldering iron is not grounded, the soldering iron tip will have a higher leakage voltage at high temperatures. Due to the circular grounding end of the soldering iron plug in the picture, it is generally not possible to insert it into the socket (it can be inserted using a universal five hole socket), so the grounding end of the plug has been cut off. Although the socket has a ground wire, the soldering iron is not grounded, indicating leakage voltage.
During testing, the red probe is connected to a screw through a small piece of solder wire, which is connected to the ground wire of the socket on the production line. In the above figure, the measured leakage voltage displayed is 42.51V. It can be seen that the leakage voltage of an ungrounded soldering iron is still relatively high at high temperatures.
When the soldering iron is not connected to the power supply, the AC voltage displayed on the multimeter is only 20.9mV.
When the soldering iron is not connected to the power supply, the AC voltage displayed on the multimeter is only 20.9mV. This reading is an interference signal in the AC voltage range, and the number is constantly changing. As can be seen from the figure, the grounding end of the temperature regulating soldering iron plug has been cut off.
2. Using a digital multimeter to measure leakage current
