There a 6 methods by which we can find out that if the capacitor is in good, bad or open, short condition, the methods are given below
1.Traditional Check and Test Method:
In this method, the capacitor is first charged by an AC or DC supply and after that, the supply is disconnected and capacitor terminals are made short.
If the capacitor produces a strong spark it is in good health and if the spark produced is weak then the capacitor is bad and needs to be replaced/repaired.
2.Testing a Capacitor using Analog Multi-meters:
In this method, the analog multimeter is switched to the OHM setting and then the terminals of multi-meter are connected to the capacitor.
- For short capacitors, low resistance will be indicated.
- For open capacitors, no results will be shown (no deflection on screen).
- For good capacitors, the resistance will go from 0 to infinite.
3.Testing a Capacitor using Digital Multi-meters:
This method requires the multi-meter to be set on OHM setting with OHM range of 1000 Ohms, then the meter leads are connected to the capacitor terminals.
- As a result of these steps, the meter will display a series of numbers for a second.
- The meter now returns to the Open-line.
- If the same numbers are displayed every time the meter is set on 1000 ohms then the capacitor is in good condition.
- If no change is observed the capacitor is dead.
4.Testing a capacitor using Capacitance Mode:
For this method the meter is set to the capacitance mode and the meter leads are connected to the capacitor, if the meter shows original value of the capacitor it is in good health otherwise the capacitor is dead.
5.Testing a capacitor using simple voltmeter:
In this method, the capacitor is disconnected from the circuit and then supplied a voltage equal to its rated voltage. The supply is then disconnected and the capacitor is then connected to the voltmeter if the voltmeter shows the value of the voltage to which capacitor was charged the capacitor is good and if the value is wrong the capacitor is dead.
6.By using time constant:
This method makes use of the time constant of the capacitor. Here, the value of capacitance is found mathematically using the formula of the time constant and then this value is compared to the original rated value of the capacitor. If the values are same then the capacitor is in good health and if the values have some difference then the capacitor needs to be replaced.