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Description
:
Inductive proximity switches are ideally suitable for no contact
sensing of metallic objects. As inductive sensors work on electromagnetic
principle, they are inherently resistant to dust, humidity and oil
in industrial environment. Besides Proximity detection, continuous
development in the field has led to new applications such as distance
measurement with Analogue Types. Low power consumption ,availability
in wide range of packages and low unit price has made them very
popular in industry.
Standard
Barrel Types
Housings of standard inductive ranges are made of Nickel coated
brass barrels. They are widely used in non-corrosive atmospheres.
Limit
Switch Style Blocks.
With housings moulded in engineering plastic
material these switches replace mechanical limit switches. KATLAX
offers Models with multiaxes sensing to adopt design flexibility.
Flat
Types.
These models in engineering plastic are best fit for conveyor belt
applications to overcome z-axis limitations. They virtually substitute
mechanical micro switches.
Slotted
Types.
Designed for RPM measurement and zero speed
detection these slotted versions are also available in engineering
plastic housings.
Design
And Principle
KATLAX Inductive Sensors are no contact type
electronic sensors comprising of three components oscillator, comparator
and output stage. Catalogue specifies sensing distance for Fe ST-37
grade steel plate and necessary Correction Factor must be considered
for different metals. ( refer table 1 ).
Operation
The oscillator creates high frequency electromagnetic
field which radiates from sensing face of the sensor. When damped
with metallic object, eddy currents are induced in metal causing
change in amplitude of oscillations. This signal is conditioned
to change Schmitt trigger output and state of output amplifier.
Analogue DC output voltage and current are available in addition
to standard PNP/NPN switching outputs.
Definitions....
Sensing
distance(Sn) :
Distance at which output signal is triggered
when standard target is moved towards sensing face.
Standard
target :
Square plate st-37 /Fe length of the side equal
to sensing face diameter.
Correction
factor(C.F.) :
If target differs from standard test target,
then the applicable published sensing distance must be multiplied
by appropriate correction factor.
| MATERIAL |
C.F. |
| Mild
Steel |
1.00 |
| Stainless
Steel |
0.70 |
| Brass |
0.45 |
| Aluminum |
0.35 |
| Copper |
0.25 |
Hysteresis(H)
:
Difference in distance between operate and release
points given in terms of percentage of sensing distance. KATLAX switches
are designed for 3% to 15% over its range of operating conditions.
Repeatability(R)
:
The repeatability of actual switching point of
two successive switching within 8 hours.
Temperature
:
The normal temperature range between 0 to 70 Deg.C.
Switching
Frequency (F) :
Highest frequency at which proximity sensor can
be switched.
Mounting
Instructions :
For Cylindrical
Forms :
Shielded
: Sensor
can be mounted flush in the metal.
Unshielded
: There
must be space equal to diameter of sensing head with no metal interference.
For
Limit Switch Styles :
40Block type switches
: Mounting should be done as shown.
Electrical
and Mechanical Specifications :
Supply
Voltage(Vb) :
Maximum ripple of 10% of supply voltage should
not be exceeded.
Voltage
Drop(Vd) :
Maximum voltage drop measured across conducting
output.
Current
Consumption(Ia) :
Maximum current drawn by switch.
Output
Load Current(IL) :
Maximum current switch can sink or source should
not be exceeded.
Output
Protection :
KATLAX switches are protected against
BACK EMF,
REVERSE POLARITY,
& INDEFINITE OUTPUT SHORT- CIRCUIT.
Magnetic
Fields :
Strong Magnetic Fields may push proximity switch
into latching condition. e.g. Induction Furnaces. Protective screening
is recommended in such cases.
Cable
Length :
KATLAX standard proximity switches are furnished with 3m Cable. Longer
lengths add capacitive coupling on output leading to switching limitations
and /or noise problems.
Status
:
KATLAX switches are provided with LED indication.
Protection
Class :
KATLAX Proximity Switches are approved for IP67 class of protection
against ingress of water at specified pressure and time conditions.
Electrical
Configurations :
NAMUR
SENSORS
These low current two wire sensors developed at KATLAX are approved
by CMRI., Dhanbad for INTRINSICALLY SAFE AREA APPLICATIONS as per
IS 5780-1980 and can be operated in Ex-PROOF areas Gr I,IIA,IIB,IIIC
.
DC/AC
SWITCHING SENSORS
These high output current driving capacity sensors are manufactured
to operate over wide range of supply conditions 10 to 30 Vdc / 40
to 250Vac.
ANALOGUE
SENSORS
These are available in standard process contol protocol viz. 4-20
mA. /0-10V output proportional to target distance.
- Metallic or Plastic
with Cylindrical, Flat, Slot or Customized Mounting, Certified
for IP 67, Short Circuit, Overload, Polarity reversal Protection.
- Reflex, Retro-reflective,
Through Beam, Colour Mark.
Range
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