When customers order electric heating tubes, the first thing they must look at when receiving the goods is the quality of the electric heating tubes.
Here are some simple ways to judge the quality of electric heating tubes:
The main confirmed parameters are: the resistance value of the heating tube, the insulation resistance value of the heating wire. Method:
1. Use a multimeter resistance file (R*1 or R*10 file) to measure the lead wire or lead rod of the electric heating tube. There are two wires or lead rods for single-phase or two-phase. Use the red and black test leads of the multimeter to test the lead wires. The resistance value R indicates that the value is within the range (R=U*U/P, U refers to the marked voltage value of the electric heating tube, P refers to the marked power value of the electric heating tube), which means that the electric heating wire of the electric heating tube is not short-circuited.
2. Use a megohmmeter (also known as a shaker, insulation resistance meter) to measure the insulation resistance value of the lead wire of the electric heating tube or the lead rod and the tube of the electric heating tube (the ground wire of the electric heating tube is connected to the tube of the electric heating tube), such as The greater the indicated value of the megohmmeter, the better, indicating that the heating tube is well insulated, but the minimum value must not be less than 2M ohms, otherwise the leakage protection switch will trip and fail to work during use.
3. Check that the power cord is not damaged and the junction box is well sealed.
