دوستان سلام و سال نو همگی مبارک. میخواستم ببینم کسی مطلبی درمورد انواع سوئیچ به هنوان مثال LEVEL SWITCH و PRESSURE SWITCHو TEMPERATURE SWITCH داره؟در حد معرفی واصول اولیه و مکانیزم عمل اونها.ممنون.
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Level Switch applications are found in all types of production, including the food industry, for monitoring one or more high/low levels on fluids or bulk material.This is applicable on all kinds of vessels e.g.:
[*=left]storage tanks
[*=left]hot product bunkers
[*=left]stirrer vessels cyclones
[*=left]sluices
[*=left]feeder chutes etc.
Measuring Principle
The level switch system is based on the physical law of the attenuation of gamma radiation as it passes through matter. In the case, there is product in between the source and the corresponding detector, the detected radiation decreases by a considerable extend. This effect corresponds to the product's presence or absence and therewith it is signalised whether the surveyed level is reached or not.
The measurement is independent of:
[*=left]High temperature
[*=left]High pressure or vacuum
[*=left]Volatile & biohazard material
[*=left]Corrosive material
[*=left]Agitators, baffles, coils etc.
[*=left]Build up on vessel walls
[*=left]Physical and chemical properties of the product and the process
Advantages
[*=left]Contactless measurement
[*=left]External mounting without modification of the existing vessel
[*=left]Lowest source activity
[*=left]Decay compensation
[*=left]Independent from chemical composition and most physical properties
[*=left]Suitable for aggressive products, high temperatures and high pressure
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[h=1]Pressure switch[/h]
A pressure switch is a form of switch that makes electrical contact when a certain set pressure has been reached on its input. This is used to provide on/off switching from a pneumatic or hydraulic source. The switch may be designed to make contact either on pressure rise or on pressure fall.
[h=2]Examples[/h][h=3]Pneumatic[/h]
Uses of pneumatic pressure switches include:
[*=left]Switching off an electrically driven gas compressor when a set pressure is achieved in the reservoir
[*=left]Switching off a gas compressor, whenever there is no feed in the suction stage.
[*=left]in-cell charge control in a battery
[*=left]Switching on/off an alarm light in the cockpit of an aircraft if cabin pressure (based on altitude) is critically low.
[h=3]Hydraulic[/h]
Hydraulic pressure switches have various uses in automobiles, for example:
[*=left]To switch on a warning light if engine oil pressure falls below a safe level
[*=left]To switch on brake lights automatically by detecting a rise in pressure in hydraulic brake pipes
[*=left]In dust control systems (bag filter), a pressure switch is mounted on the header which will raise an alarm when air pressure in the header is less than necessary to gain or decline energy beyond the set value