Method for Measuring the Quality of Electromagnets with a Multimeter
Usually, a multimeter is used to measure the DC resistance value. Small high-voltage coils typically have several hundred or several thousand ohms or a maximum of a few megaohms, and have low accuracy requirements. By comparing the measured value with the design value or other faultless equivalent coils. Low voltage coils are generally of the milliohm level, and precise resistance values cannot be measured with a multimeter (with a large error), so a dedicated direct resistance tester must be used.
But in actual measurement, it cannot be concluded that the coil is good if the measured value is the same or similar to the design value. Sometimes, if the insulation between turns or layers of the coil is damaged, it cannot be measured with a multimeter.
You can use a resistance range for measurement. First, measure the resistance using a normal solenoid coil, and then measure the problematic solenoid coil. If the resistance difference is too large, it indicates that the solenoid is not working properly.
Analysis of measuring the quality of electromagnets:
The problem with electromagnets: Sometimes the suction force is not enough to suck in, sometimes the suction force is too large to pop out too slowly, and sometimes the suction force is not suction. How do you measure electromagnets?
A multimeter can be used to measure the electromagnet, and a multimeter can be used to check the on/off resistance of the coil to determine the quality of the electromagnet.
The parameters of the coil remain basically unchanged, and the suction force is determined by the voltage, spring force, and initial position of the iron core.
Focus on checking whether the voltage fluctuates and whether the spring force is within the allowable range.
The initial position of the iron core refers to the distance between the iron block at the bottom of the offline coil of the iron core before the electromagnetic coil is powered on. If this distance is too large, it will not be able to be absorbed.
For the problem of sometimes excessive suction and slow ejection, excessive suction only affects the speed at which the iron core is sucked in, and is not related to whether it can be ejected. When the iron core is ejected, the coil has been powered off, and the speed of ejecting is determined by the spring force.
It can be seen that the problem is not in the circle, and it does not require a multimeter to measure it.
