Pepperl+Fuchs WCS Series User manual

WCS
position encoding system
Mechanics
FACTORY AUTOMATION
MANUAL

With regard to the supply of products, the current issue of the following document is ap-
plicable: The General Terms of Delivery for Products and Services of the lectrical Indus-
try, published by the Central Association of the lectrical Industry (Zentralverband
lektrotechnik und lektroindustrie (ZV I) e.V.) in its most recent version as well as the
supplementary clause: " xpanded reservation of proprietorship"
WCS position encoding system

WCS position encoding system
3
1 Introd ction................................................................................. 5
2 Declaration of conformity .......................................................... 6
2.1 CE conformity....................................................................................... 6
3 Safety ........................................................................................... 7
3.1 Symbols relevant to safety.................................................................. 7
3.2 General safety instr ctions ................................................................. 7
4 Prod ct Description ................................................................... 8
4.1 F nctional Description ........................................................................ 8
4.2 Application areas ............................................................................... 10
5 Readers ..................................................................................... 13
5.1 Mo nting ............................................................................................. 16
5.2 Plastic Lenses .................................................................................... 18
6 Code Rail ................................................................................... 20
6.1 Gro nding the Code Rail................................................................... 21
6.2 Clamping Fixt re for the Stainless Steel Code Rail ........................ 21
6.3 Identification....................................................................................... 22
7 Mo nting the Code Rail............................................................ 24
7.1 Mo nting the Code Rail with Mo nting Brackets............................ 26
7.1.1 Mounting the Code Rail on a Straight Route .................................... 29
7.1.2 Mounting the Code Rail on Curves .................................................. 30
7.2 Mo nting WCS2 Code Rail with the Al min m Profile System ..... 31
7.3 Rail Holders ........................................................................................ 35
7.3.1 Adapter Plates for Profile Rails......................................................... 36
7.3.2 Mounting the Code Rail ................................................................... 39
7.3.3 Fixed Points ..................................................................................... 41
7.3.4 The Guide Trolley............................................................................. 42
7.3.5 Grounding the Aluminum Profile System.......................................... 44

4
WCS position encoding system
7.4 Mo nting WCS3 Code Rail with the Al min m Profile System .....45
7.4.1 Rail Holders...................................................................................... 48
7.4.2 Adapter Plates for Profile Rails ......................................................... 49
7.4.3 Mounting the Code Rail....................................................................51
7.4.4 Fixed Points...................................................................................... 52
7.4.5 Vertical Curves .................................................................................54
7.4.6 Interruptions in the Profile Rail ..........................................................55
7.4.7 Suspended Mounting with Stainless Steel Code Rail ....................... 55
7.4.8 Grounding the Aluminum Profile System .......................................... 56
7.4.9 Integration of the WCS Code Rail in Conductor Lines ...................... 56

WCS position encoding system
Introduction
2014-10
5
1 Introduction
Congrat lations
You have chosen a device manufactured by Pepperl+Fuchs. Pepperl+Fuchs develops,
produces and distributes electronic sensors and interface modules for the market of
automation technology on a worldwide scale.
Symbols sed
The following symbols are used in this manual:
Handling instructions
You will find handling instructions beside this symbol
Contact
If you have any questions about the device, its functions, or accessories, please contact us at:
Pepperl+Fuchs GmbH
Lilienthalstraße 200
68307 Mannheim
Telephone: [phone]
Fax: [phone]
-Mail: [e-mail]
Note!
This symbol draws your attention to important information.

2014-10
6
WCS position encoding system
Declaration of conformity
2 Declaration of conformity
2.1 C conformity
This product was developed and manufactured under observance of the applicable uropean
standards and guidelines.
Note!
A declaration of conformity can be requested from the manufacturer.

WCS position encoding system
Safety
2014-10
7
3 Safety
3.1 Symbols relevant to safety
3.2 General safety instructions
Responsibility for planning, assembly, commissioning, operation, maintenance, and
dismounting lies with the system operator.
Installation and commissioning of all devices must be performed by a trained professional only.
User modification and or repair are dangerous and will void the warranty and exclude the
manufacturer from any liability. If serious faults occur, stop using the device. Secure the device
against inadvertent operation. In the event of repairs, return the device to your local
Pepperl+Fuchs representative or sales office.
Danger!
This symbol indicates an imminent danger.
Non-observance will result in personal injury or death.
Warning!
This symbol indicates a possible fault or danger.
Non-observance may cause personal injury or serious property damage.
Caution!
This symbol indicates a possible fault.
Non-observance could interrupt devices and any connected facilities or systems, or result in
their complete failure.
Note!
Disposal
lectronic waste is hazardous waste. When disposing of the equipment, observe the current
statutory requirements in the respective country of use, as well as local regulations.

2014-10
8
WCS position encoding system
Product Description
4 Product Description
4.1 Functional Description
The WCS position encoding system consists of two main components:
1. The code rail
The code rail carries information for the absolute code. The code rail is routed parallel to
the track for the material handling equipment and assigns a unique position to every point
on the track. It is possible to route the code rail only at points where positioning is required.
The system allows the code rail to be routed along curves and allows branches to be cre-
ated. The code rail is built to order and delivered in a bundle. Unless otherwise ordered,
the code rail always starts with the position value 0. The maximum length of the code rail
is 327 m (WCS2) or 314.5 m (WCS3). Brackets are available for mounting the code rail.
2. The reader
The U-shaped reader scans the code rail photoelectronically without touching it. very
0.833 mm (WCS2) or 0.8 mm (WCS3), the reader detects a new position value. After in-
sertion into the code rail, the reader determines the position value without reference or de-
lay. The code rail can be scanned at very high speeds. The scanning is reproducible,
reliable, and independent of temperature fluctuations. The position value can be trans-
ferred directly from the reader to the controller via a serial RS485 interface. For connection
to standard interfaces, there is a wide range of interface modules available:
• Parallel
• SSI
• PROFIBUS DP
• DeviceNet
• CANopen
• thernet
• InterBus-S
• PROFIN T
• MODBUS RTU
Up to four readers can be connected simultaneously to all interface modules with the ex-
ception of the SSI interface module.

WCS position encoding system
Product Description
2014-10
9
1. Interface module
2. Code rail
3. Reader
Properties of the WCS
■ Absolute position encoding system
■ Photoelectric principle (infrared range)
■ Proven and robust
■ asy to maintain
■ No reference points required
■ No calibration and adjustment work necessary
■ Resistant to power failure
■ Millimeter-precise positioning with absolute repeat accuracy
■ Determination of position value in real time and regardless of temperature fluctuations
■ Guaranteed reading up to a speed of 12.5 m/s
■ High resolution = ±0.4 mm
■ Variable route length: 0.1 m to 327 m
■ Coding system also suitable for curves with up to 0.5 m radius
■ A wide variety of applications, such as stock feeders, trolleys, monorail conveyors,
galvanic plants, automatic and slewing cranes, as well as elevators
■ Various mounting systems available for installing the code rail
■ Connection to any controller possible, either directly or via interface module
■ Connectivity to many fieldbus systems available
■ Support during commissioning and maintenance with extensive system diagnostics
options
1
2
3

2014-10
10
WCS position encoding system
Product Description
■ High functional reliability as a result of permanent self-diagnostics
■ Contamination warning
■ Optional heating for ambient temperatures down to -40 °C
■ Digital output of an adjustable limit speed (optional)
4.2 Application areas
The WCS can be used anywhere where material handling equipment has to be positioned
precisely. The functional principle of the WCS enables it to be used in a diverse range of
applications, such as:
■ Interruptions in the code rail (lane changes, track switches)
■ Applications with curves and circular paths
■ Use of multiple vehicles in a row
Due to the larger tolerances of the reader in relation to the code rail, in most applications the
WCS3 system can be used. In some circumstances, however, it is advantageous to use the
WCS2 in conjunction with the aluminum profile system. Here are some examples from the
variety of application options:
Stock Feeders (High-Bay Wareho se)
Trolleys, lifting gear, and transversing carriages are each positioned with one reader. The
positioning is independent of the length of the code rail and always absolutely reproducible. For
new high-bay warehouses we recommend the WCS3 system. For retrofits in older warehouses,
it may be beneficial to use the WCS2 in conjunction with the aluminum profile system:
■ asy to retrofit
■ High mechanical tolerances between the measuring system and moving carriages
possible
■ Decoupling of vehicle vibrations
Figure 4.1 Stock feeder (high-bay warehouse)
A tomatic Cranes
Automatic cranes are a typical application for the WCS2 in conjunction with the aluminum
profile system. The crane is positioned using one reader each for the crane and the trolley
movement. At each point, the guide trolley ensures the optimum position of the reader in
relation to the code rail and decouples any vibrations from the crane track. Optional cleaning
brushes for the code rail can be attached to the guide trolley. This means that the WCS2 can be
used in a very dusty environment, such as in cement works or foundries.

WCS position encoding system
Product Description
2014-10
11
Figure 4.2 Automatic crane
Galvanic plants
One or more vehicles moving in a line along a straight route. The vehicles bring the material to
be galvanized into the corresponding bath automatically. The high and adaptable light output of
the readers has enabled the WCS position encoding system to perform extremely well even
under these difficult conditions. In addition to the WCS3 system, the WCS2 with the aluminum
profile system, which is also available powder-coated, can be used.
Figure 4.3 Galvanic plant
Overhead Conveyors
Many vehicles have to be positioned on a circular track—the WCS offers the optimal solution
for this. Branches (track switches) and curves can be created. The WCS3 is particularly well-
suited for this task. After a power failure, the current position of the vehicle is transferred to the
controller immediately; the vehicle does not have to be moved. The WCS can also be used for
distances longer than 314 m.

2014-10
12
WCS position encoding system
Product Description
Figure 4.4 Overhead conveyor

WCS position encoding system
Readers
2014-10
13
5 Readers
The reader housing is made from a robust plastic and has IP54 protection. The product
contents include the mounting bracket for mounting the reader. On the inside of the reader
there are easily removable, transparent plastic lenses that protect the reading area against dirt
and damage. Identification notches can be found on these lenses. The notches are used for
adjustment of the zero point for the vertical play of the reader (= Z-axis). see image on page
14. The reference point is the top edge of the code rail. Within specified tolerances, the reader
may move around this reference point: if the vertical play on the Z-axis is exceeded, the reader
reports "OUT" to the controller (reader outside the code rail). The tolerances for the lateral play
on the Y-axis result from the gap width of the reader. The positions are reliably determined up
to a minimum of 500 mm for both an inclined position in the vertical direction and in the
horizontal direction, as well as in curves. If the position value cannot be determined, for
example due to contamination of the optical system, the reader reports a unique error code.
From a technological point of view, the WCS2B and WCS3B readers are very similar. The
resolution and the signals to the interface are almost identical. However, there are differences
in the mechanical systems and in the accessories.
WCS2B
WCS2B readers have a gap width of only 10 mm. This close proximity between the emitter and
receiver provides high contaminate burn-through power. This makes the WCS2B reader
suitable for very dirty environments such as galvanizing plants, foundries, and steel mills. An
optional guide trolley and the WCS2B rail system are specially designed for operation with
imprecise mechanical connections and where vibrations occur, for example, with automatic
cranes.
Figure 5.1 WCS2B dimensional drawing
WCS3B
WCS3B readers have a gap width of 31 mm. This results in a greater tolerance when mounting
the reader and aligning it in relation to the code rail. WCS3B systems are ideal for monitoring
conveyor belts and automated warehouse and lifting systems.
Special features of the WCS3B readers include the status L Ds for the alignment and
performance display, an optional "overspeed" output, and an optional 7-segment display for
position and diagnostic data.
WCS2B WCS3B
Resolution ± 0.42 mm
1200 pos./m
± 0.40 mm
1250 pos./m
v
max
12.5 m/s 12.5 m/s
129
10
75
40
38
33
75 115
57
M12 x 1

2014-10
14
WCS position encoding system
Readers
Figure 5.2 WCS3B dimensional drawing
Tolerance for Y- and Z-axis
WCS2B WCS3B
Y-axis ± 5 mm ± 15.5 mm
Z-axis ± 5 mm ± 14 mm
53
40.5
99
78.5
55
90
128
115
31
M12 x 1
B
Y
Z

WCS position encoding system
Readers
2014-10
15
Tolerance for inclined position α
WCS2B WCS3B
α±10° ±10°
Y
Z
α

2014-10
16
WCS position encoding system
Readers
5.1 Mounting
As a rule, the reader is mounted on the vehicle. However, the reader can also be mounted
stationary. A code rail unit can also be mounted on the carriage (vehicle identification).
A special mounting bracket is supplied with the reader. This is mounted on the carriage. If the
WCS2 is used with an aluminum profile rail system and guide trolley, the mounting bracket is
already installed in the guide trolley. On three sides of the reader housing, dovetail grooves are
integrated with a quick-action lock. If required, the reader is pushed onto the base module of
the mounting bracket via one of these grooves and engaged with a spring tongue. This quick-
action lock makes it easy to mount and quickly replace the reader when necessary without any
adjustment work. The installation location of the reader is arbitrary. The reader is not sensitive
to extraneous light.
Tolerance for inclined position β
WCS2B WCS3B
β±5° ±5°
X
Z
β
B

WCS position encoding system
Readers
2014-10
17
1. Reader
2. Quick-action lock
3. Groove
4. Mounting base
5. Base module with spring tongue
Mounting and Dismounting with the Mounting Bracket
1. Secure the mounting bracket to the carriage with size M4 screws.
2. Slide the dovetail groove on the reader onto the base module of the mounting bracket. In the
end position, the spring tongue engages audibly in the quick-action lock.
The reader is mounted.
3. For dismounting, unlock the spring tongue with a screwdriver.
4. Push the reader off the base module of the mounting bracket.
1
2
3
4
5
Note!
Mounting Direction
Mount the reader so that the electrical connecting plug points in the direction of the ascending
position values on the code rail.
Tip
Securing the Mounting Bracket
Plan elongated holes in the design of the end stop on the carriage. These allow you to correct
the position of the mounting bracket and the reader during mounting.
Caution!
Interference from strong sunlight
When planning the plant, make sure that no strong sunlight can shine directly into the reader
gap.
Caution!
Interference from contamination
When installing the reader, make sure that the reader gap is protected against dirt and any
vapors. This allows for long-term, trouble-free function.

2014-10
18
WCS position encoding system
Readers
Figure 5.3 WCS-MP1 mounting bracket
5.2 Plastic Lenses
In the event of damage or contamination, you can replace the reader's plastic lenses.
Replacing the Plastic Lenses
1. Loosen two cross-head screws on each lens.
2. Remove the lens.
3. Slide the new lens into the intended position on the inside of the reader gap.
4. Secure the lens with the cross-head screws. The maximum torque is 0.8 Nm.
The plastic lenses are available in pairs as spare parts.
Note!
The mounting bracket is identical for all readers.
12.5 40 40
105
40
58
3
6
9.5
ø 4.5
3
6
9.5
ø 8
Tip
Always replace the lenses in pairs and also replace the seals.

WCS position encoding system
Readers
2014-10
19
WCS2B WCS3B
Model number for two lenses
with seals
WCS2-PL2 WCS3B-PL2

2014-10
20
WCS position encoding system
Code Rail
6 Code Rail
The absolute code rail is different for the WCS2 system and WCS3 system Therefore, the code
rails are not interchangeable. For WCS3, the height of the code rail is always 70 mm; for
WCS2, the rail can be supplied at a height of 55 mm or 70 mm. Two different materials that
have proven successful in practice are available for the code rail: plastic laminate and stainless
steel. The code rail is delivered in a coil. Unless otherwise ordered, the code rail always starts
with the position value 0.
Laminate Code Rail
The black laminate code rail consists of a special polyester laminate. It is characterized by
good physical and chemical properties and has a low weight. The material has a high tensile
strength and behaves neutrally to oils, greases, and solvents. Because of its good resistance to
acids, alkalis, and aggressive gases, the laminate code rail is suitable for use in electroplating.
The laminate code rail is delivered with mounting holes as standard (WCS3-CS70-L1, see also
the drawing below). If you use a bracket system to mount the code rail, use of a code rail
without mounting holes is recommended (WCS3-CS70-L0).
The laminate code rail can be used in a temperature range from -40 °C ... 60 °C. Temperatures
above 70 °C lead to material deformation.
The specific thermal expansion coefficient is approximately 2.8 x 10
-5
K
-1
.
Due to its material properties, the laminate code rail must not be mounted at temperatures
below 10 °C. In applications with large temperature fluctuations (> 50 K), we recommend the
use of the stainless steel code rail.
Stainless Steel Code Rail
The stainless steel code rail is made from corrosion-resistant spring steel. It is rust-free and is
characterized by high mechanical stability and low thermal expansion.
The stainless steel code rail can be used in the temperature range -40 °C ... 80 °C.
The specific thermal expansion coefficient is 1.6 x 10
-5
K
-1
.
Warning!
Sanding dust
When mounting the laminate code rail, make sure that sanding dust from current collectors
cannot fall directly onto the surface of the code rail. When mounting the laminate code rail on
the side, mount it above the sanding lines.
Caution!
Risk of injury
Wear protective gloves when mounting the stainless steel code rail.