P9 INSTALLATION
DOL starting is the simplest, cheapest and most common starting method. It actually gives the lowest temperature
rise within the motor during startup of all the starting methods. But the drawback is starting current can be 3-8
time of full load current. Therefore, it is not recommend for pump power higher than 5.5KW in public low voltage
mains 400V.
The typical common 3 phase pump Run / Stop starter is Direct-On-Lone Starter that include:
1. Motor Circuit Breaker is a short circuit magnetic protection devices.
2. Control unit for Run and Stop operation and status monitoring.
3. Protection relay is an overload thermal protection device.
4. Single phase MCB for secondar y protection.
DOL Starter can be applied to motor connect in Delta or WYE / Star
connection.
Factor y default 3 phase motor connection is in Delta Connection
and can't be changed.
Low Voltage
Delta Connection
W2
U2
V2
U1
V1
W1
L1
L2
L3
T
1
Direct-On-Line (DOL) Starter typical wiring.
Contactor
Stop
Run
Protection
Relay
Motor
Circuit
Breaker
MCB
It is a typical wiring diagram for reference only. All electrical rating of individual device has
to match with pump's current rating.
3 phase Cable
New Wire Color Code
3 phase Cable
Old Wire Color Code
L/L1
L2
L3
N
Earth
Brown
Black
Grey
Blue
Green & Yellow
L/L1
L2
L3
N
Earth
Red
Yellow
Blue
Black
Green & Yellow
