Electric controls for automatic feed handling
electric power is easily submitted to automatic controls; because of this convenience, its use on feed handling equipment is becoming more common. heat, light, weight, tension, compression, movement, and some other variables should be used to actuate switches and achieve automatic control of materials handling systems. automatic control may exist in any degree, from the control of one simple function to the complex integration dozens of functions. the latter is usually referred to as automation. partial automation is the most practical for materials handling systems. simple repetitive operations are regulated by automatic controls and the more complicated functions by a human operator. the electric time switch is both simple and very useful for the control of materials handling equipment. the time switch can regulate both the frequency and the duration of repetitive operations. this becomes very important when you consider that most feed handling equipment has a constant processing rate. the interval timer is used to control the operational period of equipment. this may be a fan, an outside lamp, a feed grinder, or a conveyer. the adjustment of the timer determines how long the equipment will remain in operation. automatic time relays can control the sequence of several operations. this is very useful in materials handling because it is often necessary to start and stop several pieces of equipment in a definite order. the pressure switch is another very useful control device in materials handling systems. the pressure switch is used to detect the presence or absence of material on title pressure plate of the switch which will open or close a circuit. this switch can be used to turn off a conveying system after a feeder or a bin has been filled. it also can be used to start the conveying system and feed preparation equipment when the feeder or bin is emptied.
ответьте на вопросы к тексту:
1. what kind of automation is the most practical for materials handling systems?
2. what are simple repetitive operations regulated by?
3. whom are the most complicated operations regulated by?
4. what simple switch is very useful in materials handling systems?
5. what can the time switch regulate?
6. what is the interval timer used for?
7. what can automatic time relays do?
8. what is the pressure switch used for?
Объяснение:
1) partial automation
2) Simple repetitive operations are regulated by automatic controls
3) by a human operator
4) the electric time switch
5) the frequency and the duration of repetitive operations
6) to control the operational period of equipment
7) control the sequence of several operations
8) to detect the presence or absence of material on title pressure plate of the switch which will open or close a circuit, to turn off a conveying system after a feeder or a bin has been filled, to start the conveying system and feed preparation equipment when the feeder or bin is emptied