The feeder breakers are normally equipped with pyromagnetic release (inverse time thermal over-current trip and/or magnetic instantaneous trip devices). Depending of factual application, the electronic release may be used for more precise protection. Feeder breaker for steering gear motor is equipped with instantaneous trip only.

The flexibility for adding accessories such as auxiliary contacts, shunt releases, under-volt releases, lock and interlocks, etc. creates a lot of possibilities for tailoring the system to fit a wide range of applications. The actual configuration of MCCB’s shall be defined in Scope of Supply.

1.2.6 Motor Starters

All motor starters combined in the switchboards or MCC’s are of fixed mounting type. According to the respective usage and requirement, starters are available for the following functions:

- Direct on line starting (DOL) - Star/delta starting (Y/Δ) - Reversible running - Double speed running - Auto-transformer starting - Soft starting control

- Frequency converter start

The motor starters can be configured with 2 options: either Basic type or Intelligent type.

Option 1: Basic motor starter

Basic motor starters are integrated by traditional circuit breakers, contactors & thermal relays with a basic protection on the motors. The control functionality on the motor is locally achieved by various relay circuits, the remote control and alarm monitoring can be transmitted by separate I/O modules which are the integral part of Automation System by communication cables.

Depending on individual functions, typically a basic motor starter consists of, but not limited to following components:

1 pc MCCB with instantaneous tip, or motor protective C/B as per capacity 1 unit Magnetic contactor(s) & thermal relay 1 unit Ammeter & current transformer (normally for vital pumps or where required) 1 pc Hour counter (where required) 1 pc Control transformer 1 pc “Start” push button (green)