SICK MOC3ZA User manual

OPERATING INSTRUCTIONS
MOC3ZA
Standstill Monitor

Described product
MOC3ZA
Manufacturer
SICK AG
Erwin-Sick-Str. 1
79183 Waldkirch
Germany
Legal information
This work is protected by copyright. Any rights derived from the copyright shall be
reserved for SICK AG. Reproduction of this document or parts of this document is
only permissible within the limits of the legal determination of Copyright Law. Any modi‐
fication, abridgment or translation of this document is prohibited without the express
written permission of SICK AG.
The trademarks stated in this document are the property of their respective owner.
© SICK AG. All rights reserved.
Original document
This document is an original document of SICK AG.
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Contents
1 About this document........................................................................ 5
1.1 Purpose of this document........................................................................ 5
1.2 Scope......................................................................................................... 5
1.3 Target groups of these operating instructions........................................ 5
1.4 Additional information.............................................................................. 5
1.5 Symbols and document conventions...................................................... 6
2 Safety information............................................................................ 7
2.1 General safety notes................................................................................ 7
2.2 Intended use............................................................................................. 7
2.3 Requirements for the qualification of personnel.................................... 8
3 Product description........................................................................... 9
3.1 General description.................................................................................. 9
3.2 Control elements and status indicators.................................................. 10
3.3 Function of the Standstill Monitor .......................................................... 11
3.4 External device monitoring (EDM)........................................................... 12
4 Project planning................................................................................ 13
4.1 Manufacturer of the machine.................................................................. 13
4.2 Operating entity of the machine.............................................................. 13
4.3 Integrating the equipment into the electrical control............................. 13
4.3.1 External device monitoring (EDM).......................................... 13
4.3.2 Operation with DC motors....................................................... 13
4.3.3 Operation with electronic motor controllers........................... 14
4.3.4 Motors with switched windings............................................... 14
4.3.5 Connection diagrams.............................................................. 15
4.4 Testing plan............................................................................................... 17
4.4.1 Planning the thorough check during commissioning and in
certain situations..................................................................... 17
4.4.2 Planning the regular thorough check..................................... 18
5 Mounting............................................................................................. 19
5.1 Mounting the Standstill Monitor.............................................................. 19
5.2 Removing the Standstill Monitor............................................................. 19
5.3 Plug-in terminal blocks............................................................................. 19
5.4 Removing the pluggable terminal blocks................................................ 20
6 Electrical installation........................................................................ 21
6.1 Device connection.................................................................................... 21
6.1.1 Internal circuitry....................................................................... 23
7 Commissioning.................................................................................. 24
7.1 General acceptance ................................................................................ 24
7.2 Commissioning......................................................................................... 24
CONTENTS
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7.3 Check during commissioning and modifications.................................... 25
8 Troubleshooting................................................................................. 26
8.1 In the event of faults or errors................................................................. 26
8.2 Error monitoring........................................................................................ 26
8.2.1 Internal errors.......................................................................... 26
8.2.2 Wire break/offset.................................................................... 27
8.2.3 EDM error................................................................................. 27
8.2.4 Simultaneity of the measured signals.................................... 27
8.2.5 Error storage and deletion....................................................... 28
8.3 Fault indicators......................................................................................... 28
9 Decommissioning............................................................................. 32
9.1 Disposal..................................................................................................... 32
10 Technical data.................................................................................... 33
10.1 Data sheet................................................................................................. 33
10.2 Dimensional drawings.............................................................................. 37
11 Ordering information........................................................................ 38
11.1 Ordering information MOC3ZA................................................................. 38
12 Glossary.............................................................................................. 39
13 Annex.................................................................................................. 41
13.1 Checklist for initial commissioning and commissioning........................ 41
13.2 Conformities and certificates................................................................... 41
13.2.1 EU declaration of conformity................................................... 41
13.2.2 UK declaration of conformity.................................................. 42
14 List of figures..................................................................................... 43
15 List of tables....................................................................................... 44
CONTENTS
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1 About this document
1.1 Purpose of this document
These operating instructions are designed to address the technical personnel of the
machine manufacturer or the machine owner in regards to safe mounting, installation,
configuration, electrical installation, commissioning, operation and maintenance of the
Standstill Monitor.
These operating instructions do not provide instructions for operating machines on
which the MOC3ZA is, or will be, integrated. Information on this is to be found in the
operating instructions for the machine.
1.2 Scope
Product
This document applies to the following products:
•Product code: MOC3ZA
•“Operating instructions” type label entry: 8014608
Document identification
Document part number:
•This document: 8027992
•Available language versions of this document: 8014608
You can find the current version of all documents at www.sick.com.
1.3 Target groups of these operating instructions
Some chapters of these operating instructions are intended for certain target groups.
However, the entire operating instructions are relevant for intended use of the product.
Table 1: Target groups and selected chapters of these operating instructions
Target group Chapters of these operating instructions
Project developers (planners, developers,
designers)
"Project planning", page 13
"Technical data", page 33
Installers "Mounting", page 19
Electricians "Electrical installation", page 21
Safety experts (such as CE authorized repre‐
sentatives, compliance officers, people who
test and approve the application)
"Project planning", page 13
"Commissioning", page 24
"Technical data", page 33
"Checklist for initial commissioning and com‐
missioning", page 41
Operators "Troubleshooting", page 26
Maintenance personnel "Troubleshooting", page 26
1.4 Additional information
www.sick.com
The following information is available on the Internet:
•Data sheets and application examples
•CAD data and dimensional drawings
•Certificates (e.g. EU declaration of conformity)
•Guide for Safe Machinery Six steps to a safe machine
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1.5 Symbols and document conventions
The following symbols and conventions are used in this document:
Safety notes and other notes
DANGER
Indicates a situation presenting imminent danger, which will lead to death or serious
injuries if not prevented.
WARNING
Indicates a situation presenting possible danger, which may lead to death or serious
injuries if not prevented.
CAUTION
Indicates a situation presenting possible danger, which may lead to moderate or minor
injuries if not prevented.
NOTICE
Indicates a situation presenting possible danger, which may lead to property damage if
not prevented.
NOTE
Indicates useful tips and recommendations.
Instructions to action
bThe arrow denotes instructions to action.
1. The sequence of instructions for action is numbered.
2. Follow the order in which the numbered instructions are given.
✓The check mark denotes the result of an instruction.
LED symbols
These symbols indicate the status of an LED:
oThe LED is off.
ÖThe LED is flashing.
OThe LED is illuminated continuously.
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2 Safety information
2.1 General safety notes
Product integration
DANGER
The product can not offer the expected protection if it is integrated incorrectly.
bPlan the integration of the product in accordance with the machine requirements
(project planning).
bImplement the integration of the product in accordance with the project planning.
Mounting and electrical installation
DANGER
Death or severe injury due to electrical voltage and/or an unexpected startup of the
machine
bMake sure that the machine is (and remains) disconnected from the voltage
supply during mounting and electrical installation.
bMake sure that the dangerous state of the machine is and remains switched off.
Repairs and modifications
DANGER
Improper work on the product
A modified product may not offer the expected protection if it is integrated incorrectly.
bApart from the procedures described in this document, do not repair, open, manip‐
ulate or otherwise modify the product.
2.2 Intended use
The Standstill Monitor is used for the sensor-less monitoring of electric motors for
standstill. It makes possible the safe detection of the standstill of electric motors, e.g.
to enable the unlocking of guards on machine tools or to activate retaining brakes. The
Standstill Monitor can be used as per the following standards:
•IEC 61508 and IEC 61511 up to SIL3
•IEC 62061 up to SIL3
•ISO 138491 up to category 4
•ISO 138491 up to Performance Level e
The degree of safety actually attained depends on the external circuit and the design of
the wiring.
NOTICE
The Standstill Monitor complies with the requirements as defined for class B as per EN
55011:2009 + A1:2010.
Class B devices are devices that are suitable for operation in the residential sector as
well as in those sectors that are connected directly to a low voltage supply network that
(also) supplies residential buildings.
The Standstill Monitor must be used only by qualified personnel and only on the
machine where it has been installed and initialized by qualified safety personnel in
accordance with these operating instructions.
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The product may be used in safety functions.
Incorrect use, improper modification or manipulation of the product will invalidate any
warranty from SICK; in addition, any responsibility and liability of SICK for damage and
secondary damage caused by this is excluded.
2.3 Requirements for the qualification of personnel
The product must be configured, installed, connected, commissioned, and serviced by
qualified safety personnel only.
Project planning
You need safety expertise to implement safety functions and select suitable products
for that purpose. You need expert knowledge of the applicable standards and regula‐
tions.
Mounting, electrical installation and commissioning
You need suitable expertise and experience. You must be able to assess if the machine
is operating safely.
Operation and maintenance
You need suitable expertise and experience. You must be instructed in machine oper‐
ation by the machine operator. For maintenance, you must be able to assess if the
machine is operating safely.
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3 Product description
3.1 General description
Overview
The Standstill Monitor permits the sensor-less monitoring of electric motors for safe
standstill. It detects the standstill of three-phase motors, single-phase motors and
DC motors that generate a voltage due to their remanence as they coast down. By
adjusting the voltage threshold for the standstill detection (Uan) and the standstill time
(ts: time delay between the voltage dropping below the voltage threshold and switching
on the safety-related output relay) the function can be adapted to a large number of
different motors and applications.
Properties:
•safe standstill monitoring of three-phase and single-phase AC motors
•safe standstill monitoring of DC motors
•suitable for use with frequency inverters
•no external sensors necessary
•direction of rotation-independent standstill detection
•wire break detection in the measurement circuit
•adjustable voltage threshold for standstill detection
•adjustable standstill time
•LED indicators for motor standstill, wire break and supply voltage
•3 enable current paths as safe outputs for up to 250 V AC (normally open contact)
•1 positively guided N/C contact for up to 250 V AC
•1 non-safety output as application diagnostic output for 250 V AC (normally open
contact)
•2 non-safety outputs as semiconductor application diagnostic outputs for 24 V DC
Important information
WARNING
You are responsible for the correct setting of the MOC3ZA in relation to the voltage
threshold Uan and standstill time ts. The correct setting must be determined by corre‐
sponding tests under worst-case conditions.
bAlways ensure the MOC3ZA setting is safe in the context of your application.
WARNING
Test the suitability of the motor!
If the motor current is gradually reduced to zero by a frequency inverter or soft starting
device, the motor may be demagnetized.
bIn this case check whether the remaining remanence voltage is sufficient to
ensure correct standstill detection.
MOC3ZA
The MOC3ZA measures the voltage induced at the terminals of the winding by the
residual magnetization of a motor coming to a standstill. Two redundant measurement
channels (L2 against L1, and L3 against L1) are used for this purpose. If the induction
voltage on both channels drops below the configured voltage threshold (Uan) at the
same time, this means the motor of the device is coming to a standstill and the output
relay is activated, i.e. the outputs are enabled.
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To be able to adjust the device to a large number of different motors and applications,
the voltage threshold Uan is adjustable. Also adjustable is the length of time for which
the voltage must drop below Uan so that standstill is finally detected and the output
circuit is enabled (standstill time ts).
The device detects wire breaks on the measurement channels (L1/L2/L3). If a wire
break is detected, the output relay switches to the safe position (as when the motor is
running). This state is saved and can be deleted by bridging the terminals S2/X1.
The input voltages on the measurement channels (L1/L2/L3) are continuously com‐
pared. If the input voltages are different for longer than approx. 2.5s, a simultaneity
error is triggered. This error is reset when all measurement channels simultaneously
have input voltages that are above the voltage threshold Uan set.
The terminals S1/X1 are the feedback loop for monitoring externally connected contac‐
tors (EDM or contactor monitoring, N/C contact). If no external device monitoring is
required, the terminals S1/X1 must be bridged, otherwise an error message is issued.
3.2 Control elements and status indicators
Figure 1: Control elements and status indicators of the Standstill Monitor MOC3ZA
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Table 2: Status indicators
Display Meaning
PWR oNo supply voltage
O Green Supply voltage is present
O Red Internal device error
OUT O Green The outputs are released.
Ö Green Standstill time tselapsed
O Yellow The voltage on at least one of the measurement channels
(L1/L2/L3) exceeds the voltage threshold Uan.
ERR oThe device is operating correctly.
O Red Internal device error
Ö Red Error in the measurement circuit, error in the external device moni‐
toring or excessively low supply voltage UB
o LED off. Ö LED flashes. O LED illuminates.
Table 3: Control elements
Control element Function
Rotary switch Uan Voltage threshold (Uan) setting for standstill detection
Rotary switch tsStandstill time (ts) setting for enabling the safety contacts
3.3 Function of the Standstill Monitor
The supply voltage of the device is connected to the terminals A1/A2; the PWR LED
lights up O Green. In case of undervoltage, the safety outputs of the device are
generally not enabled.
If the semiconductor application diagnostic outputs are used, a supply voltage
(24VDC) must also be connected to the terminals A3 and A4.
An electric motor connected to the measurement channels L1/L2/L3 generates an
induced voltage due to the residual magnetism (remanence) as it coasts down (i.e.
if the supply voltage to the motor is switched off); the magnitude of the voltage is
proportional to the rotational speed of the motor.
This voltage is evaluated redundantly by the Standstill Monitor. For this purpose the
measurement inputs L2 and L3 are used; L1 is a common reference point. If the
voltage on both measurement inputs is below the voltage threshold Uan set, standstill is
detected.
If the voltage drops below the voltage threshold Uan, the external device monitoring
(EDM) S1/X1 is closed and the standstill time ts has elapsed, the output relay switches
on. The safety contacts 13/14, 23/24 and 33/34 close and the contact on 41/42
opens.
At the same time the signal relay is energized (signal contacts 53/54 close), the
semiconductor output ON is switched on and the OUT LED illuminates O Green. While
the standstill time ts elapses, the OUT LED flashes Ö Green.
If the voltage measured on the measurement inputs L1/L2/L3 exceeds the value for
Uan on one of the measurement channels (i.e. there is power flowing through the motor
connected or it is running under mechanical action), the output relay is switched off
immediately (the safety contacts 13/14, 23/24 and 33/34 open and the positively
guided N/C contacts 41/42 close). The signal relay drops out (signal contacts 53/54
open), the semiconductor output ON switches off and the OUT LED illuminates O Yellow
(Uan exceeded).
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Supply voltage on
PWR A1/A2
Motor on Motor standstill detected Stop Motor coasting down Wire break Reset ERR S2/X1 Motor on Wire break Motor coasting down Reset ERR S2/X1
Motor speed or
voltage on
L1/L2/L3
Wire break on
L1/L2/L3
13/14
23/24
33/34
53/54
ON
41/42
ERR
Voltage threshold Uan
Test time for the
input signals
tE= 2 … 2.5 s
tEtE
Standstill time tS
Test time on switching on PWR
Figure 2: Function diagram
3.4 External device monitoring (EDM)
External device monitoring (EDM)
The static external device monitoring monitors whether the positively guided contactors
have dropped out prior to enabling the output circuits. The N/C contacts for the external
device monitoring are connected between S1 and X1.
Further topics
•"External device monitoring (EDM)", page 13
•"Device connection", page 21
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4 Project planning
4.1 Manufacturer of the machine
The manufacturer of the machinery must carry out a risk assessment and apply appro‐
priate protective measures. Further protective measures may be required in addition to
the product.
The product must not be tampered with or changed, except for the procedures descri‐
bed in this document.
The product must only be repaired by the manufacturer of the product or by someone
authorized by the manufacturer. Improper repair can result in the product not providing
the expected protection.
4.2 Operating entity of the machine
Changes to the electrical integration of the product in the machine controller and
changes to the mechanical mounting of the product necessitate a new risk assess‐
ment. The results of this risk assessment may require the entity operating the machine
to meet the obligations of a manufacturer.
After each change to the configuration, it is necessary to check whether the protective
measure provides the necessary protection. The person making the change is responsi‐
ble for ensuring that the protection measure provides the necessary protection.
The product must not be tampered with or changed, except for the procedures descri‐
bed in this document.
The product must only be repaired by the manufacturer of the product or by someone
authorized by the manufacturer. Improper repair can result in the product not providing
the expected protection.
4.3 Integrating the equipment into the electrical control
4.3.1 External device monitoring (EDM)
The terminals S1/X1/S2 are not galvanically separated from the measuring circuit
L1/L2/L3. The terminals must therefore be controlled using volt-free contacts. The
insulation of the terminals must correspond to the insulation of the measuring circuit
L1/L2/L3. Otherwise, safe functioning of the Standstill Monitor is not guaranteed.
If no external device monitoring is required, the terminals S1/X1 must be bridged.
The external device monitoring must be wired inside the control cabinet.
Further topics
•"External device monitoring (EDM)", page 12
•"Device connection", page 21
4.3.2 Operation with DC motors
Operation with DC motors
It is possible to use the Standstill Monitor for the detection of the standstill of DC
motors if the motors generate a remanence voltage as they coast down. For this
purpose connect the measurement input terminals as for a single-phase AC motor.
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Complementary information
Since the remanence voltage of DC motors is usually a DC voltage signal, the MOC3ZA
continuously reports an offset or wire breakage error at the LED ERR and at the
semiconductor output ERR during operation and coastdown. All other functions are not
affected. Bridge the terminals S2/X1 so that the saving of this error does not prevent
the automatic release of the outputs at standstill.
Further topics
•"Error storage and deletion", page 28
4.3.3 Operation with electronic motor controllers
Operation with electronic motor controllers
It is possible to use the Standstill Monitor for the detection of the standstill of motors
with electronic motor controllers (e.g. frequency converters, brake modules), if the
latter do not supply any output voltage in case of motor standstill (i.e. in the case of
frequency inverters there must not be, e.g., any position control and in the case of
brake modules the brake voltage must be switched off).
If the frequency inverter supplies a DC offset or if there is braking with a DC voltage,
then during this time an offset or wire break error will be signaled on the ERR LED and
on the semiconductor output ERR.
This error can be reset automatically by switching off the supply voltage for a short time
or by a jumper between the terminals S2/X1.
Complementary information
In the case of operation with frequency converters, it may be necessary to use
screened measurement connection cable to the motor; the screen must be connected
to the motor.
4.3.4 Motors with switched windings
Motors with switched windings
In the case of motors with switched windings (e.g. star-delta switching, direction of
rotation reversal, pole switching) note that the measurement inputs L1/L2/L3 on the
Standstill Monitor must always be connected to the motor windings for the detection of
the standstill, otherwise the error message “wire break” will prevent the enable of the
outputs.
In the case of a three-phase connection to a motor with star-delta switching, e.g., after
shutting down the motor the star contactor must be switched on so that the connection
of L1/L2/L3 via the motor windings is ensured.
If switching on the star contactor after switching off the motor is not possible or not
desired, connect the measurement inputs of the MOC3ZA directly to one of the motor
windings in single-phase mode (see "Connecting the measurement inputs directly to a
motor winding in single-phase mode", page 15).
The same applies to motor circuits with direction of rotation reversal or pole switching.
In this case a renewed safety assessment may need to be undertaken.
If the motor windings are switched over when the MOC3ZA is connected in three-phase
mode and the resulting interruptions of the measuring circuit last longer than 2s, the
Standstill Monitor detects a wire breakage fault. To ensure this error does not remain
stored when the changeovers are completed, error storage should be deactivated by
bridging the terminals S2/X1.
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Further topics
•"Error storage and deletion", page 28
4.3.4.1 Connecting the measurement inputs directly to a motor winding in single-phase mode
Approach
1. Connect the bridged terminals L2/L3 to one end of the motor winding.
2. Connect L1 to the other end of the same motor winding.
4.3.5 Connection diagrams
1
Figure 3: Connection of the MOC3ZA to a three-phase motor
1Motor contactor
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1
Figure 4: Connection of the MOC3ZA to a single-phase motor/DC motor
1Motor contactor
1
2
3
4
i10 Lock
i10 P OFF
ON
EDM
+24 V
0 V
Figure 5: Guard unlocking with standstill detection
1Unlocking
2Reset
3Unlocking
4Standstill
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1
Figure 6: Star-delta circuit with timer relay and MOC3ZA
1Main switch
4.4 Testing plan
The manufacturer of the machine and the operating entity must define all required
thorough checks. The definition must be based on the application conditions and the
risk assessment and must be documented in a traceable manner.
The following tests must be planned:
•A thorough check must be carried out during commissioning and following modifi‐
cations.
•The regular tests of the device must fulfill certain minimum requirements.
4.4.1 Planning the thorough check during commissioning and in certain situations
Overview
Before commissioning the machine and after making changes, you must check whether
the safety functions are fulfilling their planned purpose and whether persons are being
adequately protected.
Minimum requirements
The device and its application must be thoroughly checked in the following situations:
•Before commissioning
•After changes to the safety function
•After changes to the mounting or the electrical installation
•After exceptional events, such as after manipulation has been detected, after
modification of the machine, or after replacing components
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The thorough check ensures the following:
•All relevant regulations are complied with and the device is effective in all of the
machine’s operating modes.
•The documentation accurately reflects the state/condition of the machine, includ‐
ing the protective device.
The thorough checks must be carried out by qualified safety personnel or specially
qualified and authorized personnel, and must be documented in a traceable manner.
Recommended thorough checks
•Using the checklist in the appendix, check that the protective device on the
machine is effective in all the operating modes that can be selected on the
machine.
•Ensure that all operators have been instructed by the qualified safety personnel
before they start working on a machine protected by a Standstill Monitor. This
instruction and the written documentation are the responsibility of the machine
operator.
•Checking the relevant items on the checklist.
Further topics
•"Checklist for initial commissioning and commissioning", page 41
4.4.2 Planning the regular thorough check
Overview
The purpose of regular tests is to identify any defects due to changes or external
influences (e.g. damage or manipulation) and to ensure that the protective measure
provides the necessary protection.
Minimum requirements
The following thorough checks must be carried out at regular intervals:
•Check the device for signs of misuse or manipulation
•Check the effectiveness of the mounted Standstill Monitor
•Check the safety function
Checking the effectiveness of the mounted Standstill Monitor:
1. Switch off the motor and allow it to coast down.
2. Check whether the configured values for Uan and ts are still identical to the values
determined and documented during commissioning.
3. Check that the MOC3ZA does not enable the output circuit until the time ts you
have specified and documented has elapsed.
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5 Mounting
5.1 Mounting the Standstill Monitor
Prerequisites
•The control cabinet or the mounting housing for the MOC3ZA must fulfill an
enclosure rating of at least IP54.
•The MOC3ZA is protected against manipulation, e.g., by a locked control cabinet.
•The device is mounted according to EN50274.
•Mounting on a 35mm × 7.5mm mounting rail in accordance with IEC60715.
•The module is enclosed in a 45mm wide housing.
Approach
bHang the module onto the mounting rail from above.
bLightly press down the module so it snaps onto the standard rail.
5.2 Removing the Standstill Monitor
Approach
bRemove the pluggable terminal blocks along with the wiring and end pieces.
bRelease the interlocking integrated into the housing and detach the device from
the mounting rail.
5.3 Plug-in terminal blocks
There are various connection options available for the Standstill Monitor:
•Plug-in terminal blocks with spring terminals
•Plug-in terminal blocks with screw type terminals
Figure 7: Connection options with plug-in terminal blocks
1MOC3ZA
2Connection block with spring terminals (PC or Plugin Cageclamp)
3Connection block with screw type terminals (SC or Plugin Screw)
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5.4 Removing the pluggable terminal blocks
Important information
NOTE
When removing the terminal blocks, note the correct assignment of the connections.
Ensure the disconnected terminal blocks are always reconnected to the correct slot.
You can ensure this, for example, by clearly labeling the terminal blocks.
Approach
Figure 8: Removal of the pluggable terminal blocks
1. Disconnect the device from the voltage.
2. Push the screwdriver into the recess at the front between the terminal block and
the front panel.
3. Turn the screwdriver around its longitudinal axis.
5 MOUNTING
20 O P E R A T I N G I N S T R U C T I O N S | MOC3ZA 8027992/1CUN/2022-11-14 | SICK
Subject to change without notice