Motor control centre (MCC) is heart of any industry which is primarily used for motor
control function. Most of the processes in any industry are performed by the
induction motors. Effective motor control function is the key challenge to an
electrical engineer which should help by providing accurate and online motor be
havior during normal operation along with easy and fast fault diagnosis mechanism.
The MCC system should also be capable to communicate the message that
operator can easily understand and take proper corrective actions based upon
displayed fault in form of message information on computer screen.
Presently, there are three method of motor control centre conventional named as:
i. I ndividual motor control starters
ii. Integrated motor control centre (MCC)
iii. Intelligent motor control centre (Intelligent MCC’s).
1.1 Individual Motor Control Starter
a) This is nothing except an individual starter installed near to the motor for control
and motor protection.
b) The individual starter is set of hardware consisting switch fuse unit, contactor,
bi-metal thermal over load relays with local start/stop button and indications
on front of the starter.
c) This type of starter is used only for individual operation of the particular driver
instead of group control system,
d) The motor is started with local push button stations as per requirement of the
operator and stopped. The remote operation is not envisaged in this control
system,
e) This motor control system can only offer motor thermal, single phase and short
circuit protection only.
f) The individual motor control station has following advantages:
- Cheapest one among available solutions,
- The system is very simple to operate and maintain,
- It needs low level skill operator for operation and maintenance,
- Fault traceability is very easy and quick,
- Cost of maintenance is very low,
- Can be installed near the motor or equipment,
- Very less space is required to install but it is accessible to everyone including
unauthorized people too.
g) This kind of motor control systems needs more human interventions, less safety
level, individual equipment control etc.
h) Generally, this motor control system is used for work shop machines, dewatering
pump stations, winches, auxiliary drives, standalone system etc.