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Siemens SENTRON Manual

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SENTRON
Residual current
protective devices
Technology primer
Edition
06/2018
www.siemens.com/rccb

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Summary of Contents for Siemens SENTRON

  • Page 1 SENTRON Residual current protective devices Technology primer Edition 06/2018 www.siemens.com/rccb...
  • Page 3 Preface Be it protecting, switching, measuring or monitoring – components for low-voltage power distribution from Siemens offer just the right device for all applications in the electrical installation field. Whether for use in industry, infrastructure or buildings, these products guarantee a maximum of flexibility, ease of use and safety.

  • Page 4: Table Of Contents

    Contents Product portfolio Introduction Protection through residual current protective devices Additional protection with I ≤ 30 mA Δn (previously “Protection against direct contact”) Fault protection (previously “Protection against indirect contact”) Fire protection Residual current protective devices Types of RCCBs 4.1.1 Type AC 4.1.2 Type A...
  • Page 5 Notes on installation and use General notes 5.1.1 Selection of protective devices 5.1.2 Use of residual current protective devices Choosing the right residual current protective device 5.2.1 Type A, Type F or Type B / Type B+? 5.2.2 What protection goal must be achieved? 5.2.3 What electrical interference occurs and how is it handled? Special features regarding the use of SIQUENCE universal current-sensitive...

  • Page 6: Product Portfolio

    Product portfolio 1. Product portfolio Residual current circuit breaker 5SM3 / 5SV (RCCB) • Type AC, Type A and Type F • I = 16 … 125 A • I = 10 mA … 1 A ∆n • 2-pole (1+N) and 4-pole (3+N) •...
  • Page 7 RC unit for combination with a 5SM2 miniature circuit breaker • For mounting on a miniature circuit breaker • Combined electric shock and line protection • Type AC, Type A and Type F • I = 0.3 … 100 A •...

  • Page 8: Introduction

    Introduction 2. Introduction When dealing with electricity, safety has top priority. Every electrician must be particularly conscientious when safety is concerned and must apply the required protective measures correctly. In consumer’s installations, residual current protective devices must be given unreserved preference over alternative protective devices.

  • Page 9: Protection Through Residual Current Protective Devices

    3. Protection through residual current protective devices The basic prerequisite for use of a residual current protective device in order to “automatically disconnect the power supply” as a protective measure is that an appropriately grounded protective conductor is connected to the system components and equipment to be protected.
  • Page 10 Protection through residual current protective devices Direct contact ≤ 30 mA Fig. 1: Protection against direct contact: Additional protection means measures to protect against direct contact with an active part that is energized during operation. For a proper assessment of the accident risk, it must be assumed that the contact resistance of the location is virtually zero.
  • Page 11 Protection against direct contact (additional protection) with I ≤ 30 mA Δn 10 mA 30 mA 10,000 1,000 1,000 10,000 Fig. 2: Effects of 50/60 Hz alternating current on the human body Zone : Exposure is normally imperceptible. Zone : There are generally no injurious effects or muscle spasms.
  • Page 12 Protection through residual current protective devices Residual current protective devices with a rated residual current of I ≤ 30 mA Δn meet the conditions for additional protection against electric shock (see Fig. 2): • In the case of accidental direct contact with parts that are live under operating conditions (e.g.: failure of the basic insulation, operation for other than the intended purpose, ineffective basic protection) •...

  • Page 13: Fault Protection (Previously "Protection Against Indirect Contact")

    Note While DIN VDE 0100-410:06-2007 specifies two exceptions to these require- ments, these are not generally applicable to the majority of applications. The requirement of the standard for additional protection can be avoided only in the case of socket outlets which are only used by qualified electricians and persons who have received appropriate technical instruction (e.g.

  • Page 14: Fire Protection

    Protection through residual current protective devices Indirect contact Fig. 3: Protection against indirect contact: Fault protection is understood to mean measures to protect against the contact of a human body with a part that is not live in operation but is electrically conductive. Fire protection DIN VDE 0100-482 requires measures for the prevention of fires which can be caused by insulation faults in “locations exposed to fire hazards”.

  • Page 15: Residual Current Protective Devices

    4. Residual current protective devices Types of RCCBs Residual current circuit breakers are distinguished from one another in respect of their suitability for detecting different forms of residual current (Table 1). Proper function of the RCCBs Current Type Type Type Type Type Tripping...
  • Page 16 Residual current protective devices Suitable Circuit Load current Residual current RCCB type Table 2: Possible residual current waveforms and suitable RCCBs...

  • Page 17: Type Ac

    4.1.1 Type AC Type AC RCCBs are suitable only for detecting sinusoidal AC residual currents (see circuits 1 to 3 in Table 2). This device type is not authorized in every country (e.g. Germany as per DIN VDE 0100-530) for residual current protection and cannot carry the VDE mark of conformity.

  • Page 18: Type B

    Residual current protective devices 4.1.5 Type B+ The same conditions apply for Type B+ RCCBs as for Type B residual current protective devices. It is only that the frequency range for the detection of residual currents is extended to 20 kHz: The device will trip within this frequency range below 420 mA.
  • Page 19 • CBRs are miniature circuit breakers with residual current protection in accordance with EN 60947-2 (VDE 0660-101), Appendix B. In this case, a residual-current detector is permanently installed on a miniature circuit breaker, thus ensuring residual current protection. • MRCDs are modular devices, i.e. separate modules are provided for residual current detection (via current transformers), evaluation and tripping (via miniature circuit breakers) (in accordance with EN 60947-2 (VDE 0660-101), Appendix M).
  • Page 20 Residual current protective devices MRCD RCCB RCBO PRCD SRCD Protection objectives Not for protective • Additional protection with rated residual measure according to current I ≤ 30 mA DIN VDE 0100-410, only ∆n • Fault protection with rated residual current local enhancement of >...

  • Page 21: Basic Design And Method Of Operation

    Basic design and method of operation 4.3.1 Type A RCCB An RCCB of Type A essentially consists of the following function groups: • Summation current transformer for detecting residual current • Tripping circuit with components for evaluation and holding magnet release for converting the electrical measured variable into a mechanical latch release •...
  • Page 22 Residual current protective devices Mechanics of the Secondary winding protective device Summation current Holding transformer magnet release Test button Test resistor Fig. 5: Schematic representation of an RCCB In accordance with the product standard EN 61008-1 (VDE 0664-10), the device must disconnect within 300 ms at the rated residual current.
  • Page 23 Armature Exciter Trip flux winding Permanent magnet Holding flux Fig. 6: Principle of operation of a holding magnet release Immediately above the permanent magnet lies a magnetic shunt whose primary task is to stabilize the permanent magnet’s magnetic flux. On one pole core, there is an excitation winding, which is connected to the secondary winding of the summation current transformer.

  • Page 24: Siquence Universal Current-Sensitive Rccb Type B And Type B

    Residual current protective devices The functionality of the residual current protective device can be tested using the test button available on any device. Pressing the test button generates an artificial residual current which must trip the residual current protective device. In order to guarantee protection against dangerous shock currents, the reliability of the RCCB must be tested when the installation is commissioned and at regular intervals, depending on the corresponding operating conditions.

  • Page 25: Features And Application Areas

    Features and application areas 4.4.1 RCCB RCCBs are residual current protective devices without integrated protection against overcurrent (overload and/or short circuit). A corresponding overcurrent protective device must therefore be assigned to them for overcurrent protection. The expected operational current of the circuit can be used as a basis for assessing the level of overload protection needed.

  • Page 26: Rcbo Type Ac, Type A And Type F

    Residual current protective devices 4.4.2 RCBO Type AC, Type A and Type F Residual current circuit breakers with overload protection (RCBOs) include residual current detection and overcurrent protection in one device and thus enable a combination of electric-shock protection, fire protection and line protection. The use of RCBOs has a series of advantages: •...
  • Page 27 Installation with central RCCBs Fig. 8 shows a frequent type of installation with two central RCCBs, downstream of which several miniature circuit breakers are connected for each phase conductor. kW/h RCCB2 RCCB1 Fig. 8: Installation with a central RCCB and miniature circuit breakers for feeders The RCCB provides electric-shock protection and fire protection as well as the additional protection with I ≤...
  • Page 28 Residual current protective devices Installation with RCBOs Fig. 9 shows an example of a future-oriented installation that meets all the requirements of the installation regulations and planning stipulations. kW/h RCCB Fig. 9: Example of an installation with RCBOs Each individual socket-outlet circuit now has its own RCBO, which provides complete fault, fire and line protection as well as additional protection against direct contact.

  • Page 29: Siquence Universal Current-Sensitive Rccb Type B And Type B

    Type A RCCBs to detect AC residual currents. For these reasons, Siemens introduced the universal current-sensitive Type B RCCB, which is also used for smooth DC residual currents, in 1994 – the first manufacturer to do so.
  • Page 30 Residual current protective devices It is now imperative, therefore, for the microcontroller to create the trip command. During the self-test, the trip command to the tripping relay is blocked for a short period (ms) in order to prevent real tripping. This tripping path is enabled again when the test reaches a positive conclusion.
  • Page 31 Frequency response of the Type B RCCB Tripping values for rated residual current 30 mA Tripping values for rated residual current 300 mA Tripping values for rated residual current 500 mA Upper limit according to EN 62423 for 30 mA Upper limit according to EN 62423 for 300 mA Upper limit according to EN 62423 for 500 mA Frequency (Hz)
  • Page 32 Residual current protective devices The dimensioning of the SIQUENCE Type B RCCB’s frequency response takes these boundary conditions into account, and represents a solid compromise between fire protection and operational safety. Since the influence of existing capacitive leakage currents on the tripping of the RCCB is clearly limited, the RCCB can be used in a significantly larger number of applications.
  • Page 33 Frequency response of the Type B+ RCCB Tripping values for rated residual current 30 mA Tripping values for rated residual current 300 mA Upper limit according to VDE 0600-664 for 30 mA Upper limit according to VDE 0600-664 for 300 mA Frequency (Hz) Fig.

  • Page 34: Siquence Universal Current-Sensitive Rcbo Type B And Type B

    Residual current protective devices Rated residual Maximum permissible grounding resistance current at touch voltage 50 V 25 V 30 mA 120 Ω 60 Ω 300 mA Type B: 16 Ω Type B: 8 Ω Type B+: 120 Ω Type B+: 60 Ω 500 mA 10 Ω...

  • Page 35: Rc Units For Installation On Miniature Circuit Breakers

    4.4.5 RC units for installation on miniature circuit breakers RC units are suitable for installation on miniature circuit breakers in accordance with EN 61009-1 (VDE 0664-20), Appendix G. The customer can combine these RC units with a suitable MCB for the same functionality as ex-works RCBOs. A large number of different combinations can be made up from the available RC unit and miniature circuit breaker product ranges without having to stock a large number of products.

  • Page 36: Sigres Rccbs (For Harsh Ambient Conditions)

    Residual current protective devices 4.4.6 SIGRES RCCBs (for harsh ambient conditions) When residual current protective devices are used under severe environmental conditions with increased emissions of corrosive gases, for instance in • indoor swimming pools (chlorine gas; ozone), • agriculture (ammonia), •...

  • Page 37: Type K Super-Resistant

    4.4.7 Type super-resistant Leakage currents and residual currents arising from the operation of electrical equipment cannot be distinguished. The reaction to both is the same. If a temporary high leakage current occurs, it is neither necessary nor desirable to disconnect the load from the supply. If electronic equipment is used with capacitors connected against the protective conductor in order to suppress interference, inadvertent tripping of the RCCB can occur when the equipment is switched on.
  • Page 38 Residual current protective devices 1,000 300 mA 30 mA 30 mA 1,000 I / mA Fig. 12: Break time t as a function of the tripping current I ∆ Fig. 12 shows the tripping ranges of the various versions of residual current protective devices.

  • Page 39: Type S Selective

    4.4.8 Type selective In order to achieve selective tripping in the case of series-connected residual current protective devices in the event of a fault scenario, both the rated residual current I and the tripping time of the devices must be staggered. The different Δn permissible break times of the standard and selective residual current protective devices can be taken from Fig.

  • Page 40: Versions For 50 To 400 Hz

    Residual current protective devices 4.4.9 Versions for 50 to 400 Hz Because of the principle according to which they function, residual current protective devices in their standard version are designed for maximum efficiency in a 50 Hz network. The device specifications and tripping conditions also relate to this frequency.

  • Page 41: Additional Components For Rccbs

    Additional components for RCCBs 4.5.1 Remotely controlled mechanism (RC) Favored locations for remote-controlled operating mechanisms are spacious or not continually manned work areas, such as water treatment plants or radio stations as well as automated plants for energy and operations management. Remotely controlled mechanisms are used for remote ON/OFF switching of miniature circuit breakers with or without RC unit, RCCBs, RCBOs or flush- mounting switches, and also allow local manual switching of these devices.
  • Page 42 More additional 5ST3... components, such as AS, FC, ST and UR, can be added to the right-hand side of the remotely controlled mechanism in line with the Siemens mounting concept. Remote-controlled operating mechanisms with ARD and Power have an LED display on the front of the device for displaying the switching state and for diagnostics.

  • Page 43: Auxiliary Switches

    4.5.2 Auxiliary switches Auxiliary switches can usually be retrofitted on the RCCB by the customer. They indicate the circuit breaker’s switching state. Three variants are possible (1 NO/1 NC; 2 NCs; 2 NOs). 4.5.3 Additional components Depending on the version of the residual current protective device, the following additional components can be retrofitted where required: •...

  • Page 44: Notes On Installation And Use

    Notes on installation and use 5. Notes on installation and use General notes 5.1.1 Selection of protective devices When selecting a suitable protective device for the protective measure “automatic disconnection of the power supply” in accordance with DIN VDE 0100-410 for fault protection, the conditions of disconnection depending on the supply system must be taken into account.
  • Page 45 Suitable protective devices are to be selected on this basis. Table 5 provides an overview. TN system TT system Trip currents I 230 V 230 V ≥ of overcurrent protection Protective devices for device ensuring The necessary trip currents the required ≥...

  • Page 46: Use Of Residual Current Protective Devices

    Notes on installation and use 5.1.2 Use of residual current protective devices Residual current protective devices can be combined with any other protective devices. Even if other protective measures are already installed in an existing system, residual current protection can still be used for this system or parts of it.
  • Page 47 If a residual current protective device for other protection tasks (fault protection, fire protection) is connected upstream of an RCD for additional protection (rated residual current ≤ 30 mA), this second RCD should always have a selective tripping characteristic (e.g. Type As shown in Table 5 , selective and standard RCCBs achieve the maximum permissible tripping times in both power supply systems.

  • Page 48: Choosing The Right Residual Current Protective Device

    Notes on installation and use Choosing the right residual current protective device Fig. 15 can help users to select a suitable residual current protective device: Design Selection criterion RCCB RCBO RC unit Type Equipment, circuit as per Table 2 Version Network, equipment, ambient conditions SIGRES 500 V 50-400 Hz...

  • Page 49: Type A, Type F Or Type B / Type B

    5.2.1 Type A, Type F or Type B / Type B+? The correct type of residual current protective device for each application can be selected with the help of Table 2 (in accordance with EN 50178/VDE 0160 “Electronic equipment for use in power installations” and DIN VDE 0100-530). If the electronic equipment (e.g.

  • Page 50: What Electrical Interference Occurs And How Is It Handled

    Notes on installation and use Fire protection with a rated residual current of I ≤ 300 mA ∆n In installations • at particular risk of fire (premises exposed to fire hazards), • that are primarily made of flammable construction materials, •...
  • Page 51 • Dynamic leakage currents Dynamic leakage currents are transient currents to ground or the PE conductor. They occur in the range from a few µs to a few ms, especially when devices with filter circuits are switched. Their duration depends on the time constant that is derived from the circuit impedances, and above all on the switching device that is used to connect the filter to the power supply.
  • Page 52 Notes on installation and use Overvoltages and surge current load During thunderstorms, atmospheric overvoltages in the form of traveling waves can penetrate the installation via the supply system and inadvertently trip residual current protective devices. To prevent these spurious tripping operations, our residual current protective devices must pass a test with the standardized 8/20 µs surge current waveform (see Fig.

  • Page 53: Applications

    Special features regarding the use of SIQUENCE universal current- sensitive RCCBs (Type B and Type B+) 5.3.1 Applications Typical applications that are vulnerable to smooth DC residual currents: • Frequency converters with a three-phase current connection • Medical equipment such as X-ray equipment or CT machines •...
  • Page 54 Notes on installation and use 5.3.2 Residual currents at various fault locations, with a frequency converter (FC) as an example A frequency converter (FC) is considered below as a typical example of equipment where different residual current waveforms can occur depending on the fault location (see Fig.
  • Page 55 Fault locations in section 1 (upstream of the FC) Line-frequency AC residual currents occur between the RCCB and the frequency converter (see figure 18). Protection against these purely sinusoidal 50 Hz residual currents is provided by all RCCBs (types AC, A, F and B). The section at risk is disconnected when the tripping value in the range 0.5 to 1 I is reached.
  • Page 56 Notes on installation and use Fault locations in section 2 (in the FC) Practically smooth DC residual currents occur in the frequency converter (between the input rectifier and the output electronics, i.e. in the DC link circuit) (see Fig. 19). There is reliable disconnection in the range from 0.5 to 2 I if a Δn Type B universal current-sensitive RCCB is used.
  • Page 57 Types AC, A and F RCCBs are unable to offer protection in these cases. The device does not trip because the DC residual current does not cause any change over time in the transformer induction of the RCCB which operates according to the induction principle.
  • Page 58 Notes on installation and use Modulation with AC residual current I ∆AC Tripping signal generated by I ∆AC Superposition of DC residual current I ∆DC with AC residual current I ∆AC IV Tripping signal on superimposition of DC residual current I ∆DC with AC residual current I ∆AC...
  • Page 59 Fault locations in section 3 (downstream of the FC) AC residual currents which deviate from the line frequency and the sinusoidal waveform occur between the outgoing terminal of the frequency converter and the motor. These currents represent a frequency spectrum with different frequency components (see Fig.
  • Page 60 Notes on installation and use Frequency components in the residual current of a frequency converter The frequency components in the residual current must be taken into account in addition to the tripping characteristics of the RCCB in order to assess the protective effect of this RCCB in conjunction with a frequency converter.

  • Page 61: Configuration

    5.3.3 Configuration Type B / Type B+ universal current-sensitive RCCBs must be used if smooth or nearly smooth DC residual currents can occur in the event of a fault when electronic equipment is operated (input circuits 8 to 13 in Table 2). In these cases, Type AC, A or F RCCBs may not be used to provide protection, as their tripping function can be impaired by the potential smooth DC residual currents to the extent that they are no longer able to trip even when those residual...
  • Page 62 Notes on installation and use 5.3.4 Causes of excessive leakage currents and possibilities of reducing them Causes of leakage currents Consequences EMC (input) filter capacitances between phase Highly dynamic and static conductor and PE conductor leakage currents Conductor capacities Mainly static leakage currents Making/breaking asymmetries Highly dynamic leakage currents possible...
  • Page 63 • Connect existing cable shield according to the manufacturer's information regarding the frequency converter. • Avoid the use of manually operated switching devices for normal switching in order to reduce the duration of making and breaking asymmetries to a minimum. •...

  • Page 64: Back-Up Protection

    Notes on installation and use Back-up protection Short circuit and residual currents can be up to several hundred amperes, depending on the network and system configuration. Thus, for instance, in the event of an insulation fault to the grounded exposed conductive parts of electrical equipment with a correspondingly low resistance, a short circuit-like current flows via the residual current protective device.
  • Page 65 In the case of Siemens residual current protective devices, rated switching capacity and rated residual switching capacity are not differentiated and nor are rated conditional short-circuit current and rated conditional residual short-circuit current. The reason for this is that the values for the residual and short-circuit currents can be identical in the relevant cases.

  • Page 66: Protection Against Thermal Overload

    Notes on installation and use The rated switching capacity of RCBOs is considerably higher than that for RCCBs as the MCB component, which is specially provided for short-circuit protection, performs short-circuit clearing. Should this switching capacity not be adequate, a back-up protection must also be provided here in accordance with the manufacturer's information.

  • Page 67: Troubleshooting

    Troubleshooting If a residual current protective device trips, the fi rst troubleshooting step should be to follow the procedure outlined in the diagram below (Fig. 24). Reclose RCCB if installation unchanged RCCB has tripped; insulation fault in the installation Temporary fault. Can the RCCB be closed? Test the insulation of the installation...

  • Page 68: 4-Pole Rccbs In A 3-Pole Network

    Notes on installation and use 4-pole RCCBs in a 3-pole network The 4-pole (3+N) version of the RCCB can also be operated in 3-pole systems. In this case, the 3-pole connection must be at terminals 1, 3, 5 and 2, 4, 6. The device function is not impaired as a result.

  • Page 69: Mrcds And Rcms

    6. MRCDs and RCMs Standards differentiate between modular residual current devices (MRCD, IEC 60947-2, Appendix M) and residual current-monitoring devices (RCMs, IEC 62020) and hence determine their usage. MRCDs function in the same way as RCMs do. For both MRCDs and RCMs, the residual current is measured via external summation current transformers.

  • Page 70: Residual Current Monitoring Devices (Rcms)

    MRCDs and RCMs Siemens specifies tested combinations of MRCDs, circuit breakers and shunt trips or undervoltage releases for which disconnection is guaranteed within 40 ms at 5 times the rated residual current, so that these combinations of devices meet the requirements for “protection through automatic disconnection of the power supply”.
  • Page 71 Continuous residual current monitoring can already detect and signal faults before the protective device responds. Sudden system disconnection can frequently be avoided this way. For that reason, residual current monitoring devices are primarily used in systems in which a signal, but not a disconnection, should be carried out in the event of a fault.
  • Page 72 MRCDs and RCMs RCMs as additional fire protection In accordance with DIN VDE 0100-530, RCMs coupled with switching devices with an isolating function can be used as an alternative to fire protection if residual current protective devices (RCDs) cannot be used for fire protection, because the operating current of the circuit to be protected is greater than the greatest rated current of the residual current protective devices (RCDs).

  • Page 73: Outlook

    7. Outlook There is a growing demand for residual current protective devices in electrical installations owing to the high level of protection they afford. At the same time, the widespread use of RCCB to protect a large variety of different loads means that even more complex functional requirements need to be met.

  • Page 74: Sources

    Sources 8. Sources The following sources and publications were among those used in drawing up this technology primer and can be consulted for additional information: • DIN 18015-1:2013-09 • DIN 18015-2:2000-08 • EN 50178 (DIN VDE 0160) • EN 60947-2 (VDE 0660-101) •...

  • Page 75: Appendix

    9. Appendix Key terms and definitions (according to DIN VDE 0100-200) Phase conductors (symbol L1, L2, L3) Conductors that connect current sources to current-using equipment but that do not originate at the center point or neutral point. Neutral conductor (symbol N) Conductor that is connected to the center point or neutral point and that is suitable for transmitting electricity.
  • Page 76 Appendix Exposed conductive part (of electrical equipment) Touchable, conductive component of an electrical device that is not normally live, but which may be live in the event of a fault. Electric shock Pathophysiological effect caused by an electric current flowing through the body of a person or animal.
  • Page 77 Operational current Current that should flow in the circuit during normal operation. Ground Conductive mass of ground whose electric potential is set to zero at all points according to agreement. Ground electrode Conductive part or parts that make good contact with ground and form an electrical connection with it.

  • Page 78: Power Systems And Protective Devices

    Appendix Power systems and protective devices The various power systems are defined in DIN VDE 0100-300. The permissible protective devices for these systems are listed in DIN VDE 0100-410. The power systems are identified by means of codes where the individual characters have the following meanings: 1.

  • Page 79: Tn System

    9.2.1 TN system All exposed conductive parts in the system must be connected by protective conductors to the grounded point of the supply network, which must be grounded on or in the vicinity of the associated transformer or generator. The various versions of TN system are shown in Fig.

  • Page 80: Tt System

    Appendix Fig. 29: TN-C system Permissible protective measures in TN systems: • Overcurrent protective devices • Residual current protective devices (but not in the TN-C system) 9.2.2 TT system All exposed conductive parts protected by the same protective device must be connected to a common ground electrode by means of protective conductors (see Fig.
  • Page 81 Where residual current protective devices are used, different maximum permissible grounding resistances are specified as a function of the rated residual current to meet the disconnection conditions (see Table 8). Rated residual current Maximum permissible grounding resistance at a maximum permissible touch voltage of Δn 50 V 25 V...

  • Page 82: System

    Appendix 9.2.3 IT system Live parts in IT systems (see Fig. 31) must either be insulated to ground or designed with a sufficiently high impedance. The exposed conductive parts must be grounded individually, or in groups, or with a common ground. Fig.

  • Page 83: Summary

    9.2.4 Summary Residual current protective devices can be used in all AC or three-phase network systems (TN, TT, or IT system, see Fig. 32). The protection afforded by residual current protective devices is superior to that offered by other approved protective devices, because in addition to fault protection (protection in case of indirect contact) when residual current protective devices with I ≤...

  • Page 84: Key Terms And Definitions For Specifying The Switching Capacity

    Appendix Key terms and definitions for specifying the switching capacity Rated switching capacity I of the RCCB (EN 61008-1) Prospective rms value of the short circuit current which an RCCB can make, carry and break under defined conditions. Rated switching capacity I of an RCBO (EN 61009-1) The rated switching capacity of an RCBO is the limit short-circuit breaking capacity specified by the manufacturer.

  • Page 85: Installation Regulations For Electrical Installations With Residual Current Protective Devices

    Installation regulations for electrical installations with residual current protective devices Standard Application Required I Recommended Siemens RCCB Δn (DIN VDE ... [mA] (taking into consideration the pos- or BGI ...) sible nature of the residual currents in the equipment) Type A Type F SIQUENCE...
  • Page 86 Appendix Standard Application Required I Recommended Siemens RCCB Δn (DIN VDE ... [mA] (taking into consideration the pos- or BGI ...) sible nature of the residual currents in the equipment) Type A Type F SIQUENCE SIGRES Type B/B+ 0100-723 Classrooms with experi- 10 ...

  • Page 87: 10. List Of Figures And Tables

    10. List of figures and tables Fig. 1: Protection against direct contact: Additional protection means measures to protect against direct contact with an active part that is energized during operation. Fig. 2: Effects of 50/60 Hz alternating current on the human body Fig.
  • Page 88 List of figures and tables Fig. 23: Configuration example with Type A and B RCCB Table 6: Causes of leakage currents Table 7: Maximum values Fig. 24: Troubleshooting flowchart Fig. 25: 4-pole RCCB in a 3-pole network Fig. 26: MRCD Type B and summation current transformer Fig.
  • Page 90 Published by Siemens AG 2018 Siemens AG Energy Management Siemensstr. 10 93055 Regensburg Germany Order No. EMLP-T10158-00-7600 Dispo 25600-0618-2.0 Printed in Germany Subject to change without notice The information in this document contains general descriptions of the technical options, which may not always be available in each case.

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