SCHUNK EGP User guide

System description
Electric gripper EGP with
safety functions

Imprint
2
01.00 | Electric gripper EGP with safety functions | System description | en | 1381596
Imprint
Copyright:
This manual is protected by copyright. The author is SCHUNK GmbH & Co. KG. All rights re-
served. Any reproduction, processing, distribution (making available to third parties),
translation or other usage - even excerpts - of the manual is especially prohibited and re-
quires our written approval.
Technical changes:
We reserve the right to make alterations for the purpose of technical improvement.
Document number: 1381596
Version: 01.00|14/01/2019|en
© SCHUNK GmbH & Co. KG
All rights reserved.
Dear Customer,
thank you for trusting our products and our family-owned company, the leading techno-
logy supplier of robots and production machines.
Our team is always available to answer any questions on this product and other solutions.
Ask us questions and challenge us. We will find a solution!
Best regards,
Your SCHUNK team
SCHUNK GmbH & Co. KG
Spann- und Greiftechnik
Bahnhofstr. 106 – 134
D-74348 Lauffen/Neckar
Tel. [phone]
Fax [phone]
[email protected]
schunk.com

Table of contents
01.00 | Electric gripper EGP with safety functions | System description | en | 1381596
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Table of contents
1 General.................................................................................................................... 4
1.1 About this manual ................................................................................................ 4
1.2 Applicable documents .......................................................................................... 4
1.3 Components for the system setup ....................................................................... 5
2 Technical data.......................................................................................................... 6
3 Design and description............................................................................................. 7
3.1 Example system setup Systemaufbau .................................................................. 7
3.2 Description ........................................................................................................... 8
4 Functional description ............................................................................................. 9
4.1 Definition of the safe state of the gripper............................................................ 9
4.2 Block diagram ..................................................................................................... 10
4.3 Superordinate control system ............................................................................ 10
4.4 Safety control system ......................................................................................... 11
4.5 Program sequence.............................................................................................. 12
5 Assembly and installation .......................................................................................13
5.1 Assembly ............................................................................................................ 13
5.2 Commissioning ................................................................................................... 14
5.3 Commissioning checklist..................................................................................... 15
6 Appendix ................................................................................................................17
Wiring diagram 1 (Pilz) ....................................................................................... 18
Wiring diagram 2 (LTI) ........................................................................................ 19

General
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01.00 | Electric gripper EGP with safety functions | System description | en | 1381596
1 General
1.1 About this manual
This manual contains the information for a system configuration of
the EGP electric gripper with a safety control system for imple-
menting the safety functions SOS (safe operating stop) and STO
(safe torque shutdown).
This system description does not constitute a complete document-
ation. For each application, a risk assessment has to be prepared
and applicable standards must be identified and applied.
In addition to these instructions, the documents listed under Ap-
plicable documents [}4] are applicable.
1.2 Applicable documents
• Assembly and operating manual for gripper EGP
• Assembly and operating manual of the sensor - IN 40*
• DGVU Certificate, Certificate No. MF 15008 *
• DGVU Certificate, Certificate No. MF 17022 *
• Secure control documentation (installation and programming
guide) **
The documents marked with an asterisk (*) can be downloaded on
our homepage schunk.com
SCHUNK assumes no responsibility for the currentness, correct-
ness and completeness of the documents indicated with (**).

General
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5
1.3 Components for the system setup
NOTE
For monitoring of redundant sensor signals, SCHUNK recommends
inductive proximity switches IN 40.
The following components are required for the system setup:
• Electric gripper EGP
• 4 x sensors
– e.g. inductive proximity switches
IN 40/S-M8, SCHUNK Id-No. 0301474
• Sensor bracket (2x)
–SCHUNK Id-No. 9700901
• Spacer sleeve for adjusting the sensor position
–SCHUNK Id-No. 5509536
• Sensor distributor
• Safety control system
–e.g. PILZ PNOZmulti or LTI SMC1-Z10

Technical data
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01.00 | Electric gripper EGP with safety functions | System description | en | 1381596
2 Technical data
Notes on the technical data are included in the respective document-
ation of the individual components, Applicable documents [}4].

Design and description
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3 Design and description
3.1 Example system setup Systemaufbau
Example system setup with safety control system
1 Sensor IN 40 4 Gripper power supply
cable
2 Sensor distributor 5 gripper
3 Safety control system
(e.g. PILZ PNOZmulti)
6 Sensor bracket
Superordinate
control system
Gripper
Superordinate
control system
Gripper
Monitoring level
Setup, conventional (left) and with safety function (right)

Design and description
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01.00 | Electric gripper EGP with safety functions | System description | en | 1381596
3.2 Description
During the system setup, a monitoring level is created with a
safety control between the system's superordinate control and the
gripper.
As a result, the position of the gripper fingers can be monitored in-
dependently of the superordinate control and, if necessary, the
gripper can be disconnected from the supply voltage and thereby
placed to a safe state.
The monitoring level differentiates between two modes:
• Monitored operation
• Released operation
In monitored operation mode, the functions of the monitoring
level are active.
In released operation mode, the functions are not active and haz-
ards may arise. In released operation mode, the customer must
ensure that the plausibility of the sensor signals is monitored and
evaluated.
The monitoring level comprises two safety functions and the eval-
uation logic:
• Safe Operating Stop (SOS)
– Safe monitoring of the position of the gripper fingers
Cross-attached sensors monitor the position of the gripper
fingers.
• Safe Torque Off (STO)
– Safe deactivation path of the gripper
The gripper is deactivated by switching off the power supply.
• Evaluation logic
– The monitored positions are evaluated by the safety control.
If necessary, the control makes the decision to place the
gripper in safe state and maintains this state.

Functional description
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4 Functional description
4.1 Definition of the safe state of the gripper
The safe state of the gripper is a state in which no danger to per-
son or machine arises from the gripper.
For the system setup, this means that there are the following two
safe states depending on the position of the gripper fingers:
• Safe state1
–Position of the gripper fingers is defined
The gripper maintains its position and gripping force to avoid
losing a workpiece that it may be holding.
• Safe state2
–Position of the gripper fingers is not defined
To avoid crushing, the power to the gripper is disconnected.
The change from safe state1 to safe state2 is made as soon as the
position of the gripper fingers is undefined.
This is the case, for example, when a gripped workpiece is re-
moved by force application from the gripper during monitored op-
eration, no release or the logical release signal low or Emergency
Stop. If a workpiece is removed, the gripper fingers move until a
signal change is made to one of the sensors (overrun traverse). If
the configured gripping force is very low, it is possible that the
gripper fingers maintain the position without an overrun.
The switch from safe state2 to safe state 1 is is not allowed.
It is possible to exit safe state 1 by reenabling or confirming.
Exiting safe state 2 is only possible by solving and acknowledging
the existing fault and then reenabling. This prevents unwanted or
unexpected reactivation. Alternatively, agreeing and subsequent
confirmation can ensure that the gripper is powered until the con-
firmation button is released or cut off (panic function).

Functional description
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01.00 | Electric gripper EGP with safety functions | System description | en | 1381596
4.2 Block diagram
Gripper open 2
Non-safe (superordinate) control system Power supply
Ub = 24V DC ±10%
Sensor logic Evaluation logic Relays
Gripper open 1
Gripper closed 1
Gripper closed 2
Gripper closed 2
Gripper closed 1
Gripper open 2
Gripper open 1
Open
Close Close
Open
Reset
Confirmation button
Enable
Emergency Stop
Interface system
Safety sensors and evaluation logic
Gripper voltage supply
EGP S
S
S
S
Sensor distributor SCHUNK products
Block diagram
4.3 Superordinate control system
The superordinate control system can be run in safe on non-safe
mode. There are no special requirements for the superordinate
control system. It must be ensured that the connections are made
for safety technology comply with the requirements of
ENISO13849-1.
When using a safe superordinate control system, the sensor and
evaluation logic that must be executed safely can be implemented
in the superordinate control system. In this case, no additional
control system is needed.
It must be ensured that the safety connections comply with the
application-specific requirements of ENISO13849-1.
If an external relay is used, it may be necessary to use additional
signals for monitoring and safe state change. When using integ-
rated safe relays, this may be adopted by the safety control sys-
tem.
NOTE
In release mode, the superordinate control must check the plaus-
ibility of the redundant sensor signals provided by the safety con-
trol system. In release mode, the sensor signals are merely looped
through the safety control system.