Points | Static Relays | Electromagnetic Relays |
---|---|---|
Power consumption | Very less 1 milliwatt | High 2 watt |
Moving contacts | No moving contacts. So, No problem of Arcing No needs to replace contacts. | Moving contacts are present. Problem like Arcing, Replacement of contacts is necessary. |
Effect of Gravity(Gravitational force) | No effect of Gravity on operation of static relay. | Gravitational force can affect the relay. |
Position of relay | Relay can be installed at any location and at any position. | This relay has to be installed straight only and away from magnetic field. |
Functions | 1 relay can perform various functions. (1 relay can be used as over current relay, under voltage relay etc.) | 1 relay can perform only 1 function. (1 relay can be used as over current only for under voltage we use another relay). |
Delay in operation | Easily provided | Not provided |
Size | Compact (small) | Large |
Accuracy and speed | High | Less |
Effect of vibrations and shocks | No or less effect | Yes, vibrations directly |
External supply required | Yes, Dc supply is required for level detector, timing circuit etc. | No need of external supply |
Voltage change | Can damage this relay because electronic components are used. | Change of voltage causes no effect. |
Cost | Costly | Cheap. (Not costly) |
Effect of temperature | May damage the electronic part | No effect of temperature. |
Note: Last points are Disadvantages of static Relays. Similar advantages and disadvantages of Microprocessor Based relays.