A DOL starter connects the motor terminals directly to the
power supply. Hence, the motor is subjected to the full
voltage of the power supply. Consequently, high starting
current flows through the motor. This type of starting is
suitable for small motors below 5 hp (3.75 kW). Reduced-
voltage starters are employed with motors above 5 hp.
Although DOL motor starters are available for motors less
than 150 kW on 400 V and for motors less than 1 MW on 6.6
kV. Supply reliability and reserve power generation
dictates the use of reduced voltage or not
To reduce the starting current of an induction motor the
voltage across the motor need to be reduced. This can be
done by autotransformer starter, star-delta starter or
resistor starter. Now-a-days VVVF drive used extensively
for speed control serves this purpose also.
Please Help Members By Posting Answers For Below Questions
how oti and wti connections are different from each other?
How we calculate DC inducation moter Amp?
Sir pls give me formula......
why transmission is only 3 phase and not 2 or 4 or poly
How to control motor gearbox speed and friquency?
If length of cable and dia given, how to measure the
in what type of applications v can use q meter?
what do u understand about FACTS? how they are useful?
We have 110Vac ,10A ac supply which is converted into
110VDC & How much DC current? which factor is reqired for
dc current calulation?
how to select the double earth conductor if 21A full load?
difference between ac series and parallel circuit
How to findout raw or ups power? its not indicated in
when we design electrical schemes of 11/.415kv
distribution..wen and were should we show the relays??what
is the function of it?for example..we place EFR Relay CT
between transformer neutral link and transformer earth.Like
this what are the other type of relays we should
use?why?where?Explain please..Thank you
in my working site. momentary jerck in electrical supply ocurred frequently which cause of multiple losses in our electrical equipements. how can we protect our electrical machines and equipements in this situation.
If we use 250A MCCB as a incomer in Control panel for a fault level of 50kA for one second ,assuming temperature rise from 85 Deg. to 100 Deg , Then what will be the Aluminium Bus-bar size for 250A MCCB?
Explain in detail.
Magnetizing current for induction motor compared to
A equal B more
C less D depends on load
how much LT load can bear by the 100 KW HT connection.