Ours is a petrochemical plant dated back to 1990s.... We have our own power plant...Why no starter is used for the 415v motors starting output ranges from 55kw-160kw...is this is because system is stable & healthy and by using starters maintenance will increase and motor will undergo transition which can damage motors? But in college there mentioned about a lot of atarters...................pls anybody

What are you using to turn on these motors?

They are all directly online...These motors are used as centrifugal pumps,blowers,compressors .... ...thank u

GIRI, if your motors are directly online, you wouldn't be able to shut them off.

I wonder if he is confusing a "soft start" motor starter with an "across the line" starter.
Wouldn't be out of the norm for 415v to just have a regular starter. Punch the button and throw the starter contactors together.
D

1. In industrial applications all Low Voltage AC induction motors rated below 75 kW (100 hp), except those with special requirements (example: crane, hoist) are started using Direct On-line (DOL) starters. Typically NEMA 1-4 starters or equivalent are used in LV MCC. Two types of DOL starters: reversible & non-reversible are used. Reversible starters are used for either motor operated valves (MOVs) or motor operated dampers (MODs). Non-reversible starters are used for pumps, fans, blowers, etc.

2. For LV AC induction motors of 100 hp and above, we again use DOL starting. MCC is not used; instead we use LV Switchgear (example: Secondary Unit Sub-station or SUS). LV SWG contains electrically operated feeder breakers.

3. For LV DC motors starting, we use starter panel to limit the current during starting.