IFM 402946 User manual

UK
Info card
Inductive sensors
21
Operating voltage The voltage range in which the sensor functions reliably. A stabilised and smoothed
direct voltage should be used! Take into account residual ripple!
Utilisation category AC units: AC-140 (control of small electromagnetic loads with holding currents
< 200 mA)
DC units: DC-13 (control of solenoids)
Hysteresis Difference between the switch-on and the switch-off point.
Short-circuit protection ifm sensors which are protected against excessive current by means of a pulsed
short-circuit protection. The inrush current of incandescent lamps, electronic relays
and low resistance loads may cause this protection to cut in and turn the sensor off!
Standard target Square-shaped steel plate (e.g. S235JR) of a thickness of 1 mm with a side length
equal to the diameter of the sensing face or 3 x S
n
, depending on which value is the
highest.
Product standard IEC 60947-5-2
Repeatability Difference between any two S
r
measurements. Max. 10 % of S
r
.
Leakage current Current for the internal supply of 2-wire units; also flows through the load when the
output is blocked.
Switch point drift The shifting of the switch point owing to changes in the ambient temperature.
Switching frequency Damping with standard target at half S
n
. The
ratio damped to undamped (tooth to gap) = 1 : 2.
2a
a
a
S
n
2
Protection rating IPxy According to IEC 60529
IP68 Test condition: 1 m water depth for 7 days
IP69K To ISO 20653 (replacement for DIN 40050-9)
Current consumption Current for the internal supply of 3-wire DC units.
Transport and
storage conditions
Unless otherwise indicated in the data sheet, the following applies:
Transport and storage temperature:
Min. = - 40 °C.
Max. = max. ambient temperature according to the data sheet.
The relative air humidity (RH) must not exceed 50 % at +70 °C.
At lower temperatures, a higher air humidity is permissible.
Shelf life: 5 years.
Transport and storage height: no restrictions.
Degree of soiling Inductive proximity sensors are designed for degree of soiling 3.
Maintenance, repair and disposal If used correctly, no maintenance and repair measures are necessary.
Only the manufacturer is allowed to repair the unit.
After use dispose of the unit in an environmentally friendly way in accordance with
the applicable national regulations.
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This info card is to be regarded as a supplement to the main position sensors catalogue and to the individual data
sheets. For further information and contact addresses please visit our homepage at www.ifm.com.
Intended use
While in use the products are exposed to influences which may have an effect on function, life, quality and reliability of
the product.
It is the customer’s responsibility to ensure that the products are suitable for the intended application. This applies in
particular to applications in hazardous areas and with adverse environmental influence such as pressure, chemicals,
temperature fluctuations, moisture and radiation as well as mechanical stress, especially if the products are not installed
properly.
Using the products in applications where the safety of people depends on the function of the product is not permitted.
Non-compliance may result in death or serious injuries.
Operating principle of an inductive proximity switch
Coil and capacitor form an LC resonant circuit, also called
basic sensor.
Eddy current losses in electrically-conductive materials are
used for a switching signal.
① Connection ⑤ Coil
② Housing ⑥ Alternating electromagnetic field = active zone
③ Downstream electronics ⑦ Target = electrically conductive material
④ Capacitor
Important Glossary
Active zone / active face Area above the sensing face in which the sensor reacts to the approach of the target.
Output function Normally open: object within the active zone
> output is switched.
Normally closed: object within the active zone
> output is blocked.
Programmable: choice between normally closed or normally open.
Positive switching: positive output signal (to L-).
Negative switching: negative output signal (to L+).
Rated insulation voltage AC units depending on UB: 140 V AC or 250 V AC
DC units with protection class II: 250 V AC
DC units with protection class III: 60 V DC
Rated short-circuit current for short-circuit-proof units: 100 A
Rated impulse withstand voltage AC units depending on UB: 140 V AC = 2.5 kV or 250 V AC = 4 kV
(≙ overvoltage category III)
DC units with protection class II: 4 kV (≙ overvoltage category III)
DC units with protection class III: 0.8 kV (≙ overvoltage category II)
Power-on delay time The time the sensor needs to be ready for operation after application of the operating
voltage (in the millisecond range).
1D2226 / 06 11 / 2018

UK
Info card
Inductive sensors
43
Sensing range (referred to the standard target)
Sn
+ 10 %
+
10 %
-
10 %
-
10 %
SrSu
min
Su
max
Sa
Nominal sensing range S
n
= characteristic value of the unit
Real sensing range S
r
= individual deviation at room temperature between 90 % and 110 % of S
n
Useful sensing range su= switch point drift between 90 % (S
u
min
= S
a
) and 110 % (S
u
max
) of S
r
Reliable sensing range
= operating distance S
a:
= reliably switched between 0 % and 81 % of S
n
Safe switch-off distance = S
u
max
+ max. hysteresis = 143 % of S
n
Correction factors
V2A
100
S
r
[%]
50
0
Al
Ms
Cu
*
* Standard target
Values → data sheet
Exception K1 units:
Same sensing range for all
Influence of the target size
100
Sr[%]
50
0
0,2 0,5 1,0
x axis: ratio actual target / standard target
Lateral approach and ranges (valid for structural steel, e.g. S235JR)
0
Sn
a
d
d
6Q
[6Q
1
 G
①
Typical switch-on curve (for slow approach)
②
Typical switch-off curve (for slow approach)
③
Poor repeatability
④
Good repeatability
Good repeatability of the switch point means: The closer the
target is positioned to the sensing face, the better.
General recommendation:
a = 10 % of the nominal sensing range
①
Distance to the background
②
Recommended target distance
③
Recommended degree of coverage of the sensing
face
④
Recommended target size
Tips on flush and non-flush mounting in metal
Installation instructions cylindrical designs
Flush: Non-flush:
2x Sn

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Info card
Inductive sensors
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Electrical connection
The unit must be connected by a qualified electrician.
①
Use a miniature fuse according to the technical data sheet, if specified.
Recommendation: Check the safe functioning of the unit after a short circuit.
② Negative switching
③ Positive switching
④ Sensor 1
⑤ Sensor n
Connection systems
+U
B
/ L1
0V / N
+U
B
0V
+U
B
0V
Two-wire technology
(negative or positive switching)
3-wire technology
(negative or positive switching)
4-wire technology
(positive switching, normally closed and
normally open)
Series connection (AND)
+U
B
0V
+U
B
/ L1
U
1
U
n
U
L
0V / N
Series connection of 3-wire units
Max. 4 units. Power-on delay times,
voltage drops and current consumptions add up.
U
B min
(sensor) and U
HIGH min
(load) must remain
unchanged.
Series connection of 2-wire units
Not recommended because of undefined operation
when blocked! Use special types which can be
connected in series (max. 2 units).
Voltage drops add up.
Installation instructions rectangular designs
Flush: Non-flush:
h
a2xa
2xa
h
a
1,5xa
h = any
a
a2xa
2xa
a
a
1,5xa
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If the required clear space is not observed for non-flush units, the sensor is predamped. This may lead to perma-
nent switching.
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Possibly deviating installation instructions for rectangular units with increased sensing range
→ Notes on mounting and operation.
Minimum clearance for installing units of the same type (side-by-side installation)
Applies to cylindrical and rectangular sensors.
Flush: Non-flush:
8xSn
2x Sn
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The minimum distance between units may only be disregarded for units with different oscillator frequencies or
different sensing principles.

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Info card
Inductive sensors
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Parallel connection (OR)
+U
B
0V
Parallel connection 3-wire units
The current consumption of all non-switched units adds
up. The units can be used in combination with mecha-
nical switches.
Parallel connection 2-wire units
Not possible.
Configuration of cables
and connectors
Colours: BK: black, BN brown, BU: blue, WH: white
Standard configuration for 3-wire DC:
Cable Terminal chamber US-100 plug
L+ BN 1 / 3 Pin 1 / BN
L– BU 2 / 4 Pin 3 / BU
Output BK X Pin 2 / WH
Pin 4 / BK
Pin connection of the
US-100 connections (view onto
the plug of the unit)
Pin 4: BK
Pin 1: BN
Pin 3: BU
Pin 2: WH
For the cable and the pin configuration as well as the unit data of special
versions please refer to the wiring diagrams in our main catalogue for position
sensors.