Pepperl+Fuchs SC2-2 User manual

Instruction manual
Control unit SC2-2
FACTORY AUTOMATION
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With regard to the supply of products, the current issue of the following document is applicable: The General
Terms of Delivery for Products and Services of the Electrical Industry,
published by the Central Association of the Electrical Industry (Zentralverband Elektrotechnik und Elektroin-
dustrie (ZVEI) e.V.)
in its most recent version as well as the supplementary clause: "Expanded reservation of proprietorship"
We at Pepperl+Fuchs/VISOLUX recognize a duty to make a contribution to the future.
For this reason, this printed matter is produced on paper bleached without the use of chlorine.
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Control unit SC2-2
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
1
1 SC2 control system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.1 Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.2 Product description and features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2 The SC2-2 control unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.1 Product description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.2 Working principle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.3 Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.4 SC2-2 connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
2.5 SC2-2 displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
3 Operating modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
3.1 Start/restart interlock (Restart) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
3.2 Relay monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
4 Setup and assembly of the light barriers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
5 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
5.1 SL light barriers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
5.2 Message outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
5.3 Safety outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
6 Commissioning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.1 Adjust protective beams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.2 Layout with adjustable mirror . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.3 Verifying functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
6.3.1 Test of detection capability of the installed electrosensitive protection device . . . . . . . . . . . . . . . . . . . . . . . . . . .23
6.3.2 Test of start/restart interlock and startup enable (restart/start) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
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Control unit SC2-2
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
2
6.3.3 Testing the test connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
6.3.4 Test of relay monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
6.3.5 Principle of operation of the OSSD outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
7 Periodic checkup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
8 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
9 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
9.1 Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
9.2 Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
9.3 Accessories. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
9.4 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
10 Sample circuits for SC2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
11 Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
12 Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
12.1 Construction and equipping of safety equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
12.2 Use and installation of protective equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
13 Certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
14 Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Please note!
These operating instructions contain information on the intended use of the product and serve to protect
users from danger. They must be read and observed by all persons who implement, use, care for, maintain
and monitor this product. This product can only fulfill the tasks for which it is intended if it is used, cared for,
maintained and monitored in accordance with the instructions of Pepperl+Fuchs/Visolux.
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Control unit SC2-2
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
3
The warrantee undertaken by Pepperl+Fuchs/Visolux for this product becomes null and void if it is not used,
cared for, maintained and monitored in accordance with the instructions of Pepperl+Fuchs/Visolux.
Before selecting and using the product, an evaluation must be performed to determine whether it is suitable
for the purpose in question. The selection and range of application are not subject to the influence of Pep-
perl+Fuchs/Visolux. Our liability is therefore limited to consistent quality of the product.
The product must be regularly monitored and maintained by professionals. The results of inspections and
maintenance tasks must be kept in logs. Only original Pepperl+Fuchs/Visolux parts must be used for repair
jobs.
Changes to the devices or components and the use of defective or incomplete devices or components are
not permitted. Repairs to devices or components may only be performed by Pepperl+Fuchs/Visolux or au-
thorized work shops. These work shops are responsible for acquiring the latest technical information about
Pepperl+Fuchs/Visolux devices and components.
Repair tasks made on the product that are not performed by Pepperl+Fuchs/Visolux are not subject to influ-
ence on the part of Pepperl+Fuchs/Visolux.
Our liability is thus limited to repair tasks that are performed by Pepperl+Fuchs/Visolux.
The preceding information does not change information regarding warrantee and liability in the terms and
conditions of sale and delivery of Pepperl+Fuchs.
This device contains sub-assemblies that are electrostatically sensitive. Only qualified specialists may open
the device to perform maintenance and repair tasks. Touching the components without protection involves
the risk of dangerous electrostatic discharge, and must be avoided. Destruction of basic components
caused by an electrostatic discharge voids the warrantee!
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Control unit SC2-2
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
4
Symbols used
This manual uses symbols to present important information on operating the SC2-2 and working safely with
it. The meaning of these symbols is as follows:
Subject to technical modifications.
Recommendation for the user
Observing these notes will make it easier to place the system in operation and to work with the
SC2-2.
Refers to a hazard or an immediate danger.
Failure to observe such instructions may result in damage to property, serious injury or death.
Information
Danger!
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SC2-2 control unit
SC2 control system
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
5
1 SC2 control system
1.1 Intended use
In combination with light barriers of type SLA, the SC2 control system represents a photoelectric protective
device. Protective beams are formed between transmitters and receivers.
Applicable safety rules, standards and requirements must be observed during usage, and the specific re-
quirements in the application in question must be taken into consideration.
1.2 Product description and features
The SC2 analysis system is a electrosensitive protection device of Type 2 (EN 61496-1 or IEC 61496-1)
or Category 2 (EN 954-1).
System features:
- Selectable start/restart interlock (restart interlock RI)
- Selectable relay monitor (RM)
- Red transmitter light for easy adjustment of light barriers
- Function reserve display on each receiver
- 2 LEDs to make it easy to pinpoint errors
This system must only be used in accordance with intended purpose as electrosensitive pro-
tection device for securing access to hazardous points and areas. Any use not in accordance
with these conditions does not comply with usage in accordance with the intended purpose.
Danger!
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SC2-2 control unit
The SC2-2 control unit
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
6
2 The SC2-2 control unit
2.1 Product description
With its light barriers of Type SL, the SC2-2 control unit represents a one or two-beam photoelectric protec-
tive device. It consists of 2 modules,
- the OSSD Module with a 2-channel relay output (OSSD) and
- the light barrier module.
2.2 Working principle
Two protective beams are generated by the two light barriers that can be connected to the light barrier mo-
dule. Depending on the type of light barriers, the detection range of the protective beams may be 10 m,
30 m or 65 m. Interruptions in a light beam are determined by the light barrier module.The OSSDs and the
OSSD message output in the OSSD Module are turned off. Downstream equipment in the machine control
system responds by turning off the dangerous motion.
The startup/ restartlock and monitoring ofEDM feedback (relay monitor) can be turned on oroff as required
with switches on the SC2-2.
Internal tests ensure functional safety even if no external tests are performed. In addition, there is a test
input that the operator can use to initiate the test externally. The OSSDs are turned off when this happens.
If no errors are detected during the test, the OSSDs switch backon after 150 ms. If the start/restartinterlock
is activated on the control unit, the "Restart" (Start) function is turned on after the test has been successfully
completed.
If an error is detected by the test, the OSSDs remain in the Off state. In addition, a flashing signal is gene-
rated on the "Readiness for startup" output (flashes at a rate of once per second) and the two error LEDs
on the SC2-2 display the error that was detected.
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SC2-2 control unit
The SC2-2 control unit
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
7
After the operating mode is changed or after an error is eliminated, a reset must be performed by briefly
turning off the operating voltage.
2.3 Layout
An electrosensitive protection device of the type
described here consists of:
- An SC2-2 control unit (light barrier module,
OSSD module)
- One or two light barriers of Type SLxx
- (Optionally) a power pack (for power supply with
alternating current)
The SC2-2 is housed in a case suitable for moun-
ting on a top hat section rail. The installation width
is
45 mm.
The following operating modes can be set as desi-
red with DIP switches that are accessible after the
case is opened
- Start/restart interlock (restart interlock RI)
- Relay monitor (RM)
(located in the light barrier module). Figure 2.1:SC2-2 control unit
Light-barrier module OSSD-module
13 14 15 16
9 10 11 12
1 2 3 4
5 6 7 8
29 30 31 32
25 26 27 28
R1
R2
E1
E2
ON
OFF
START
SC2-2
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SC2-2 control unit
The SC2-2 control unit
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
8
Figure 2.2: Principle of operation of the SC2-2
2.4 SC2-2 connections
Terminals are used to connect the light barriers, inputs and outputs and the voltage supply. Four terminals
are combined to form each terminal block. These terminal blocks can be disconnected, thus making it easy
to switch devices.
A light barrier channel that is not in use is jumpered (see section 5.1)
Safety core
Emitter 1 Receiver 1
Light barriers
control
Test initiationTest
Restart
24 V DC
Restart
(RI)
Relay monitor
(RM)
Indicators
Signal outputs
OSSD-
control
Power supply
Emitter 2 Receiver 2
SC2-2
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SC2-2 control unit
The SC2-2 control unit
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
9
Terminal Assignment Function
1 pnp output readiness for
startup message Option for connecting external indicator lamps to indicate restart (start) or error message (see section 3.1)
2 PNP output OSSD reporting
OFF Option for connecting external indicator lamps to indicate the OSSD state Off
3 PNP output OSSD reporting
ON Option for connecting external indicator lamps to indicate the OSSD state On
4 0 V internal Reference point for pnp outputs
5 Startup enable for input (RI) Normally open contact for start/restart interlock. It should be wired in if no function is acti-
vated (see section 3.1)
6 24 V internal
7 Relay monitor input (RM) Relay monitor input. It should be wired in if no function is activated (see section 3.2)
8 24 V internal
9 24 V DC Supply voltage connection, protected from reverse polarity
10 0 V
11 24 V internal Normally open contact for testing or error enable
12 Test input
13 OSSD1.1 OSSD relay output 1 NO (normally open)
14 OSSD1.2
15 OSSD2.1 OSSD relay output 2 NO
16 OSSD2.2
Table 2.1: Connections of the SC2-2 OSSD module
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SC2-2 control unit
The SC2-2 control unit
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
10
Table 2.4: Connection assignment of light barriers
Terminal Assignment Function
25 LS2-T Transmitter 2 connection
26 LS2-T 0V
27 LS2-R 0V Receiver 2 connection
28 LS2-R
29 LS1-T Transmitter 1 connection
30 LS1-T 0V
31 LS1-R 0V Receiver 1 connection
32 LS1-R
Table 2.2: SC2-2 connections for light barrier module
SC2-2 light barrier module Receiver Transmitter
Conductor Pin Conductor Pin
LS2-T transmitter 25 BK (black) 4
26 BU (blue) 3
LS2-R receiver 27 BU (blue) 3
28 BN (brown) 1
LS1-T transmitter 29 BK (black) 4
30 BU (blue) 3
LS1-R receiver 31 BU (blue) 3
32 BN (brown) 1
Table 2.3:
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SC2-2 control unit
The SC2-2 control unit
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
11
Figure 2.3: SC2-2 connections
Restart 1
OSSD OFF 2
OSSD ON 3
0 V 4
13
14
15
16
Test +U 11
Test 12
Restart 5
Restart +U 6
RM 7
RM +U 8
supply 24 V 9
supply 0 V 10
ready to restart (yellow)
OFF (red)
ON (green)
K1
F1
Test
K1K
0 V
+ 24 V DC
Restart
Indicator
Output
OSSD
Input
Sensor
25 LS2-T
26 LS2-T 0 V
27 LS2-R 0 V
28 LS2-R
29 LS1-T
30 LS1-T 0 V
31 LS1-R 0 V
32 LS1-R
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SC2-2 control unit
The SC2-2 control unit
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
12
2.5 SC2-2 displays
Displays for the switching state of the OSSD and status displays for indicating the operating status are lo-
cated on the front plate of the two modules of the SC2-2.
.
If an error is present, the yellow LED flashes, indicating readiness for startup. The red LEDs E1 and E2 dis-
play the error that has been determined.
Display LED Meaning
OFF Red OSSDoutput turnedoff
ON Green OSSDoutput turned on
Start Yellow Continuous light:Protective field free, OSSD off, readiness for
startup, activate restart button
Flashing System error (see Status E1, E2)
R1 Yellow Status of light barrier 1
Off: Interrupted
On: Light beam free
Flashing: Light beam free, level below function reserve:
R2 Yellow Status of light barrier 2
Off: Interrupted
On: Light beam free
Flashing: Light beam free, level below function reserve
Table 2.5: Status displays
13141516
91011 12
1 2 3 4
5 6 7 8
29303132
25262728
R1
R2
E1
E2
ON
OFF
START
SC2-2
yellow
red
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SC2-2 control unit
Operating modes
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
13
3 Operating modes
The operating modes of the SC2 can be adjusted using DIP switches. Two switches must be activated to
set an operating mode. The DIP switches are located inside the housing of the light barrier module.
To activate the DIP switches, pull out the right sub-assembly. To do this, press on the upper and lower un-
locking mechanism with a screwdriver. The sub-assembly can be pulled out as far as the holding mecha-
nism and the DIP switches are then accessible.
Afterthe operating mode is changed, a reset should be triggered by turningoff the operatingvoltage briefly.
You should note on the manufacturer's rating plate (figure 3.2) with indelible ink which operating mode was
selected. The operating mode that is set should be monitored by an appropriate check (see section 6.3).
E1 E2 Meaning
Off Off Internal error
On Off DIP switch setting incorrect
Off On Fault in ext. contactors (relay monitor)
On On Transmitter connection short circuit
Table 2.6: System error displays
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SC2-2 control unit
Operating modes
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
14
When the control unit is delivered, the relay monitor (RM) is turned off and start / restart interlock (RI) is
turned on.
Figure 3.1: Position of the DIP switches Opening the housing
DIP switches
1234
Start/restart interlock (RI) X X
Relay monitor (RM) X X
Table 3.1: Function of the DIP switches
ON
1234
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SC2-2 control unit
Operating modes
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
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15
Figure 3.2: Adhesive label for marking the operating mode
3.1 Start/restart interlock (Restart)
If the protective beams are free and the start/restart interlock operating mode is activated, do not turn
the OSSDs and the OSSD-ON message on. The "Restart“ output is activated and the corresponding yellow
display LED lights up. After the "Restart“(Start) button is pressed, the OSSDs and OSSD-ON messageturn
on and the "Readiness for startup" output is turned off.
3.2 Relay monitor
With the OSSD switch outputs, the SC2 is able to perform safety-related monitoring of time-correlated ex-
ternal switching elements with the aid of feedback contacts. Normally closed contact of force-guided relays
should be used as feedback contacts. The feedback contacts of all downstream external switching ele-
ments should be wired in series. Series switching should be connected on the first side with the positive
voltage supply (Terminal 8) and on the other side with Terminal 7.
The feedback contacts of the external switching elements must ensure a reliable contact at a voltage of 20
V and a current of 6 mA. Resistance to peak voltages of 6 kV must be guaranteed between the feedback
contacts and other contacts that are at low voltage in accordance with the low voltage directive.
Operating Mode:
RI
RM
X
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SC2-2 control unit
Operating modes
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
16
Figure 3.3: Sample connection of relay monitor
The work circuit of the external switching elements must be protected by a fuse with a nomi-
nal value of maximum 60 % of the load capacity of the contacts to prevent the contacts from
fusing. The external switching elements are monitored with a delay of 180 ms following the
switching process. If the new switching state is not assumed by the time the monitoring
period expires (180 ms), the SC2 switches into interlock state and shows the cause of the
error on the error LEDs (E1 and E2). This error should be acknowledged after the cause is
eliminated by a reset on SC2.
Information
13 14 15 16 7 8
SC2
K1
K1K
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SC2-2 control unit
Setup and assembly of the light barriers
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
17
4 Setup and assembly of the light barriers
Safety light barriers should be arranged so that the transmitters
connected to the various SC2 light barrier modules cannot di-
rect beams at the receivers of other control units.
Safety light barriers must be mounted in such a manner that it
is not possible to reach the hazardous area by bypassing the
protective beams.
Figure 4.1:Minimum distance between the electrosensitive pro-
tection device and the hazardous area
It must not be possible:
- to crawl under the lowest beam,
- to climb over the highest beam or
- to walk between two beams
To calculate the minimum distance of the photoelectric sensor from the hazardous area, please refer to the
applicable requirements and standards.
Danger zone
Minimum interval S
Sending unit
Protective field
Receiving unit
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SC2-2 control unit
Setup and assembly of the light barriers
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 67 79 90 91 • Internet http://www.pepperl-fuchs.com
18
In accordance with EN 999, the minimum distance may be calculated by the formula:
S = K · T + C
Where:
S = the minimum safety distance in mm, i.e. the distance from the hazardous area to the protective field
K = the constant in mm/s for the approach speed
T = the total response time in s,
T = t1+t2
t1: response time of the protective device 30 ms
t2: response time of the machine
C = additional distance in mm. This frequently depends on how far a person
can enter into the hazardous area before the protective equipment is triggered.
According to EN 999, the following heights are recommended for individual beams parallel to the floor if the
risk evaluation permits it:
Number of beams Height above the reference level
in mm
1 750
2 400, 900
Table 4.1: Distances between protective beams above the floor
Care should be taken that reflecting objects that could result in mirroring of
an obstruction are not located within the transmitter or receiver lobe (prEN
61496-2).
Information
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