Some of the pump application like emergency backup pumps firefighting pumps etc. And from the motor protection relay nc auxiliary the neutral wire goes to the contactor coil a1 terminal.

Beechhurst Inc Multi Mode Starter Motor Protection Module
Dol starter remote control wiring diagram. Akrtechnical dolstartercontrolwiring hi i am abhilash k r welcome to our malayalam youtube channel akrtechnical. Dol starter control power wiring diagram overload indicator wiring in malayalam. The wiring of direct on line control circuit starter is following. These two buttons ie. I have used the same setup upto 125 kw. Green and red or start and stop buttons control the contacts.
The connection of contactor can be done among relay coil supply voltage as well as thermal overload. The wiring diagram for a dol stater is shown below. The dol starter comprises of an mccb or circuit breaker contactor and an overload relay for protection. A direct online starter consits of two buttons a green button for starting and a red for stopping purpose of the motor. Working principle of dol starter. The dol starter connects the 3 phase voltage supply ie.
When the start button is pressed current will flow through one phase to the control circuit and the contactor coil to the other phase. Dol starter control diagram three phase. Cheap dol starter dcsremotelocal startstop where we should usethe name dol is called as direct online starter. In which the neutral n wire goes to thermal overload relay nc contacts the neutral wire is also connected to the light indicator. R phase y phase and b phase to the induction motor terminals. How dol starter control diagram works when we press the start button to start the motor the relay gets the phase and circuit completed thus coil energizes and contactors produce magnetic fieldthe main contactor closes and motor gets the supply and the motor startswhen we press the stop button the circuit will interrupt and the motor stop.
The l1 contactor is connected from normally open no to r phase using mccb. The complete wiring shown in dol diagram. Normally it gets one phase constant from incoming supply voltage a1when coil gets second phase relay coil energizes and magnet of contactor produce electromagnetic field and due to this plunger of contactor will move and. The dol starter main terminals are connected between the mains supply terminals and motor terminals while the control circuit is energized with two terminals of three phase supply as illustrated in figure. Direct on line starter wiring diagram. The main heart of dol starter is relay coil.
Less than 10 hp motor we can use dol starter. The control circuit and the power circuit. There are two types of circuits in the dol starter diagram given above.