Germany Pepperl+Fuchs proximity switch selection 4 steps introduction

The purpose of Pepperl+Fuchs proximity switch selection is to determine which type of switch is the most suitable application. This depends on the material properties of the target being measured.
If the target is metal, then an inductive proximity switch is required.
If the target is made of plastic, or paper, or liquid (oil or water), granules or powder, then a capacitive proximity switch is required to detect.
If the target itself is magnetic or can carry (install) a magnetic block, the magnetic proximity switch is a suitable option.
step 1
By shell shape
Housing material
The standard housing material is:
stainless steel
Brass nickel plated or brass plated with fluorine
Crastin
Ryton
Polyamide
Crastin is a semi-crystalline PBT and is a reinforced glass fiber. Its casting characteristics are very good, corrosion resistance, heat and cold resistance, carbohydrate resistance, acid resistance, sea water and 70 degrees of hot water.
P+F uses Ryton, a crystalline PPS, because it can withstand temperatures from 150 to 200 degrees, and the electronic components are encapsulated in the sensor housing with a resin under vacuum.
Cable material
PVC is a standard cable used in the electronics industry. It is moderately resistant to oils, greases and has good corrosion resistance.
PUR is oil resistant, grease, solvent, corrosion resistant and not easily damaged.
Silicon has good temperature resistance, moderate corrosion resistance, oil, grease and solvent.
Step 2
Sensing distance
The sensing distance is one of the most important parameters of the proximity switch. It depends mainly on the size of the sensor (coil or capacitor). Other influencing factors are the size of the target, the material and the ambient temperature.
For magnetic proximity sensors, the arrangement of the corresponding magnetic blocks and the strength of the magnetic field are also a key factor in determining the sensing distance.
Step 3
According to electrical parameters and wiring
Straight line two-wire system, Z type
This form of operation works by connecting the load in series with the sensor supply loop. Most of them allow reverse polarity wiring, and many also have short circuit protection. The rest also have reverse polarity protection function and short circuit protection function. In the OFF state of the switch, there is a small leakage current. In the ON state of the switch, there will be a small voltage drop on the switching element. Such proximity switches have the following forms:
Normally open
Normally closed
Normally open or normally closed
DC three-wire system, type E
The load of these proximity switches is separately connected to the power supply. They have overload protection, short circuit protection and reverse polarity protection. Its leakage current is negligible.
Step 4
According to other technical parameters