What are the advantages and disadvantages of both electrical and pneumatic control systems on ships ?
Electrical Control System
No air compressor and associated machinery required.
High efficiency since there is no leakages.
Very little affected by normal temperature variations.
Electric cables are cheap and easy to lay.
The system require uninterrupted power supply with no voltage fluctuations.
Standby batteries required in case of power failure.
There is risk of fire due to overheating. Expensive intrinsically safe / explosion proof equipment may be required.
Moisture may cause damage to the system.
Damage readily occurs in the event of a fire.
Not affected by ship’s power supply variations for short term.
No heat generated and hence no risk of fire.
Actuators are cheaper and accurate than electric systems.
Simple control air piping system.
Require air compressor and associated systems.
A clean, dry and oil free supply of good quality air is essential for satisfactory operation of the system.
Good quality air require driers, filters with drains, etc. which increases maintenance.
May have transmission lags in large systems.