The direct online or dol starter employs full voltage or across the line starting technique where the motor is directly connected to full voltage through mccb or circuit breaker and relays for overload protection. Dol starter control diagram three phase.
Motor Control Direct On Line Starter Electric Equipment
Direct online motor starter wiring diagram. The dol starter joints the 3 phase main wiring with the induction motor namely l1 l2 and l3 when the start switch is pressed. The direct on line motor starter dol consist a mccb or circuit breaker contactor and an overload relay for protection. Despite this direct connection no harm is done to the motor. A wiring diagram of a dol starter is. In this article we will discuss dol starter direct online starter working principle and construction dol starter diagram control diagram power circuit and wiring single 3 phase starter direct on line is the simplest and cheapest method used for starting three phase motor. Generally the direct online starter working can be done in two different stages namely dol starter control circuit and dol starter power circuit.
Electromagnetic contactor which can be opened by the thermal overload relay under fault conditions. The 3 phase dol starter wiring diagram is shown below. The connection of contactor can be done among relay coil supply voltage as well as thermal overload. The wiring of direct on line control circuit starter is following. The l1 contactor is connected from normally open no to r phase using mccb. A dol motor starter contains protection devices and in some cases condition monitoring.
In dol starter an induction motor is connected directly across its 3 phase supply and the dol starter applies the full line voltage to the motor terminals. The simplest form of motor starter for the induction motor is the direct on line starter. This is why such a starter is used with induction motors rated below 5 hp.
Gallery of Direct Online Motor Starter Wiring Diagram
