The disadvantages of group drive electric machines is/are
Right Answer is:
Can’t be used for constant operation
Disadvantages of Group driver electric drive
Group drive is seldom used these days due to the following disadvantages :
- Group drive does not give a good appearance (owing to the use of line shafting pulley and belts) and is less safe to operate.
- In group drive, the speed control of the individual machine is very cumbersome using stepped pulleys, belts, etc.
- The noise level at the working site is quite high.
- This system is unreliable since any fault in the driving motor renders all the driven equipment idle.
- A considerable amount of power is lost in the energy transmitting mechanism. If all the machines driven by the line shaﬁ do not work together, the main motor runs at a reduced load. Consequently, it runs with low efficiency and with poor power factors.
- Group drive cannot be used where constant speed is required as in the paper and textile industry.
- The flexibility of the layout of different machines is lost since they have to be so located as to suit the position of the line shaft.
Group drive is adopted, when existing factories are changed from engine drive to electric motor drive simply by replacing the oil or steam engine with an electric motor of corresponding output retaining all the old shafts and belts.