The direct-on-line starter is the cheapest motor starting method. In this method, full voltage is applied to the motor terminals. Here a comprehensive DOL starter selection tool, which can help you calculate the appropriate rating of the contactor, fuse, circuit breaker, and overload relay used in a DOL starter circuit.
Motor data input
|Enter the motor rated voltage||V|
|Enter the motor rated power|
|Enter the motor Efficiency||95%|
|Enter the motor Power factor||0.85|
|Motor Starting Current||A|
DOL Stater rating
|Required fuse rating|
|Required Thermal Circuit Breaker rating|
|Minimum contactor current rating|
Parts of a DOL starter
This calculator can help you determine the rating of all power circuit components of a DOL starter. An DOL starter consists of the following parts.
- Circuit breaker or fuse (Sometimes both) – for short circuit protection.
- Overload relay – for overload protection.
- Contactor – for switching.
Learn in detail:
How to use the DOL starter selection tool?
The above tool requires following data for calculation:
- Motor Type – Single-phase or three-phase. (Mandatory)
- Motor rated power in HP or kW. (Mandatory)
- Input supply voltage. (Mandatory)
- Motor Efficiency as per nameplate – (if known).
- Rated power factor (if known).
After entering the required data, click on the “Calculate” button to find out the required fuse rating, Circuit Breaker rating, contactor current rating, and overload setting.