SIST EN 50090-5-2:2020
(Main)Home and Building Electronic Systems (HBES) Part 5-2: Media and media dependent layers - Network based on HBES Class 1, Twisted Pair
Home and Building Electronic Systems (HBES) Part 5-2: Media and media dependent layers - Network based on HBES Class 1, Twisted Pair
This European Standard defines the mandatory and optional requirements for the medium specific physical and data link layer for HBES Class 1 Twisted Pair TP1.
Data link layer interface and general definitions, which are media independent, are given in EN 50090 4 2.
Elektrische Systemtechnik für Heim und Gebäude (ESHG) - Teil 5-2: Medien und medienabhängige Schichten - Netzwerk basierend auf ESHG Klasse 1, Twisted Pair
Systèmes électroniques pour les foyers domestiques et les bâtiments (HBES) - Partie 5-2: Medias et couches dépendantes des medias - Réseau basé sur HBES Classe 1, Paire Torsadée
Le présent document définit les exigences obligatoires et facultatives relatives à la couche physique et de liaison des données spécifiques à un média, pour les HBES de classe 1 Paire torsadée TP1.
Les définitions de l'interface de la couche liaison de données ainsi que les définitions générales, qui sont indépendantes des médias, sont données dans l'EN 50090 4 2.
Stanovanjski in stavbni elektronski sistemi (HBES) - 5-2. del: Mediji in nivoji, odvisni od medijev - Omrežja, ki temeljijo na HBES razreda 1, zviti par
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 50090-5-2:2020
01-junij-2020
Nadomešča:
SIST EN 50090-5-2:2005
Stanovanjski in stavbni elektronski sistemi (HBES) - 5-2. del: Mediji in nivoji,
odvisni od medijev - Omrežja, ki temeljijo na HBES razreda 1, zviti par
Home and Building Electronic Systems (HBES) Part 5-2: Media and media dependent
layers - Network based on HBES Class 1, Twisted Pair
Elektrische Systemtechnik für Heim und Gebäude (ESHG) - Teil 5-2: Medien und
medienabhängige Schichten - Netzwerk basierend auf ESHG Klasse 1, Twisted Pair
Systèmes électroniques pour les foyers domestiques et les bâtiments (HBES) - Partie 5-
2: Medias et couches dépendantes des medias - Réseau basé sur HBES Classe 1,
Paire Torsadée
Ta slovenski standard je istoveten z: EN 50090-5-2:2020
ICS:
35.240.67 Uporabniške rešitve IT v IT applications in building
gradbeništvu and construction industry
97.120 Avtomatske krmilne naprave Automatic controls for
za dom household use
SIST EN 50090-5-2:2020 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 50090-5-2:2020
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SIST EN 50090-5-2:2020
EUROPEAN STANDARD EN 50090-5-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2020
ICS 35.100.20; 97.120; 35.100.10 Supersedes EN 50090-5-2:2004 and all of its
amendments and corrigenda (if any)
English Version
Home and Building Electronic Systems (HBES) Part 5-2: Media
and media dependent layers - Network based on HBES Class 1,
Twisted Pair
Systèmes électroniques pour les foyers domestiques et les Elektrische Systemtechnik für Heim und Gebäude (ESHG) -
bâtiments (HBES) - Partie 5-2: Medias et couches Teil 5-2: Medien und medienabhängige Schichten -
dépendantes des medias - Réseau basé sur HBES Classe Netzwerk basierend auf ESHG Klasse 1, Twisted Pair
1, Paire Torsadée
This European Standard was approved by CENELEC on 2020-01-09. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 50090-5-2:2020 E
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Contents
European foreword . 4
Introduction. 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviations . 7
3.1 Terms and definitions . 7
3.2 Abbreviations . 8
4 Requirements for HBES Class 1, Twisted Pair Type 1 (TP1-64 and TP1-256) . 9
4.1 Physical layer requirements – Overview . 9
4.2 Requirements for analogue bus signals . 12
4.2.1 General . 12
4.2.2 Specification of logical “1” . 12
4.2.3 Specification of logical “0” (Single) . 13
4.2.4 Specification of logical “0” (overlapping) . 14
4.2.5 Analogue requirements within a transmitted character . 15
4.2.6 Simultaneous sending / collision behaviour . 16
4.3 Medium attachment unit (MAU) . 16
4.3.1 General . 16
4.3.2 Requirements within a physical segment . 16
4.3.3 Remote powered devices (RPD) . 24
4.4 Twisted Pair Type 1 bus cable . 25
4.4.1 Requirements . 25
4.4.2 Measurement of continuous magnetic and electrical interference
respectively transient induced differential voltages . 26
4.5 Topology . 27
4.5.1 Physical segment . 27
4.5.2 Bridge . 27
4.5.3 Router, subline, main line and zone . 28
4.5.4 Gateways to other networks . 29
4.6 Services of the physical layer type Twisted Pair Type 1 . 30
4.6.1 General . 30
4.6.2 Physical_Data service . 30
4.6.3 Physical_Reset service . 32
4.7 Behaviour of the physical layer type Twisted Pair Type 1 entity . 32
4.8 Data link layer type Twisted Pair Type 1 . 32
4.8.1 General . 32
4.8.2 Frame formats . 33
4.8.3 Medium access control . 38
4.8.4 Data link layer services . 41
4.8.5 Data link layer protocol . 44
4.8.6 State machine of data link layer . 46
4.8.7 Parameters of data link layer . 46
4.8.8 Reflections on the system behaviour in case of L_Poll_Data
configuration faults . 47
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4.8.9 The data link layer of a bridge . 47
4.8.10 The data link layer of a router . 47
4.8.11 Externally accessible bus monitor and data link layer interface . 47
Bibliography . 48
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European foreword
This document (EN 50090-5-2:2020) has been prepared by CLC/TC 205, “Home and Building Electronic
1
Systems (HBES)”
The following dates are fixed:
• latest date by which this document has (dop) 2020-10-10
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2023-04-10
standards conflicting with this document
have to be withdrawn
This document will supersede EN 50090-5-2:2004 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
EN 50090-5-2 is part of the EN 50090 series of European Standards, which will comprise the following
parts:
— Part 1: Standardization structure;
— Part 3: Aspects of application;
— Part 4: Media independent layers;
— Part 5: Media and media dependent layers;
— Part 6: Interfaces;
— Part 7: System management;
NOTE Part 2 has been withdrawn.
———————
1
This document was prepared with the help of CENELEC co-operation partner KNX Association, De Kleetlaan 5, B-
1831 Diegem.
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Introduction
According to OSI, Physical Layers consist of the medium, the cable, the connectors, the transmission
technology etc. which refers to their hardware requirements. In this document however, the status of the
Physical Layer as a “communication medium” is emphasized.
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1 Scope
This document defines the mandatory and optional requirements for the medium specific physical and
data link layer for HBES Class 1 Twisted Pair TP1.
Data link layer interface and general definitions, which are media independent, are given in
EN 50090-4-2.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 50090-1, Home and Building Electronic Systems (HBES) — Part 1: Standardization structure
EN 50090-2-2, Home and Building Electronic Systems (HBES) — Part 2-2: System overview — General
technical requirements
EN 50090-3-2, Home and Building Electronic Systems (HBES) — Part 3-2: Aspects of application — User
process for HBES Class 1
EN 50090-4-2, Home and Building Electronic Systems (HBES) — Part 4-2: Media independent layers —
Transport layer, network layer and general parts of data link layer for HBES Class 1
EN 50290 (series), Communication cables
EN 61000-4-5, Electromagnetic compatibility (EMC) — Part 4-5: Testing and measurement techniques —
Surge immunity test (IEC 61000-4-5)
EN 61000-6-1, Electromagnetic compatibility (EMC) — Part 6-1: Generic standards — Immunity for
residential, commercial and light-industrial environments (IEC 61000-6-1)
EN 61000-6-2, Electromagnetic compatibility (EMC) — Part 6-2: Generic standards — Immunity for
industrial environments (IEC 61000-6-2)
HD 21.2 S2, Polyvinyl chloride insulated cables of rated voltages up to and including 450/750 V — Part 2:
Test methods (IEC 60227-2)
HD 22.2 S2, Rubber insulated cables of rated voltages up to and including 450/750 V — Part 2: Test
methods (IEC 60245-2)
IEC 60189-2, Low-frequency cables and wires with PVC insulation and PVC sheath — Part 2: Cables in
pairs, triples, quads and quintuples for inside installations
IEC 60332-1, Tests on electric cables under fire conditions — Part 1: Test on a single vertical insulated
wire or cable
IEC 60754-2, Test on gases evolved during combustion of materials from cables — Part 2: Determination
of acidity (by pH measurement) and conductivity
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3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 50090-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
HBES class 1 twisted pair type 1
physical layer specification for data and power transmission on a single twisted pair, allowing
asynchronous character-oriented data transfer in a half-duplex, bi-directional communication mode, using
a specifically balanced/symmetrical base-band signal coding with collision avoidance under SELV
conditions
3.1.2
distributed power supply
powers the bus in a distributed way by a number of the devices connected to the line (compared to a
centralized power supply)
3.1.3
logical tag extended HEE
usage of the L_Data_Extended frame dedicated to extended group addressing
3.1.4
remote powered devices
RPD
do not extract their energy for the application circuit and the bus controller from the bus but from another
independent source of energy, e.g. mains
Note 1 to entry: Owing to the reduced DC power consumption of RPD, a bus line equipped with such devices
requires less power from the installed Power Supply Unit (PSU). The connection of bus-controller and application to
the same electrical potential reduces the effort of galvanic separation in RPD.
3.1.5
TP1 backbone couplers
15 can be used to couple up to 16 zones to a full sized TP1 network
3.1.6
TP1 backbone line
main line of the inner zone is called backbone line
3.1.7
TP1 bridge
four TP1-64 physical segments can be combined to a line by using bridges
Note 1 to entry: 256 devices can then be connected to such a line.
3.1.8
TP1 line
consists of a maximum of 256 devices, either directly connected in case of TP1-256 or separated over 4
physical segments in case of TP1-64, each with 64 devices
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3.1.9
TP1 line couplers
routers that combine lines to a zone
3.1.10
TP1 logical unit
converts the serial bit stream to octets and octets to the serial bit stream, which is a serial stream of
characters
3.1.11
TP1 medium access unit
converts information signals to analogue signals and vice versa, typically extracts DC power from the
medium
3.1.12
TP1 main line
inner line of a zone
3.1.13
TP1 physical segment
smallest entity in the TP1 topology
Note 1 to entry: To a physical segment up to 64 devices can be connected in case of TP1–64 and 256 in case of
TP1–256.
3.1.14
TP1 Polling Master
Poll_Data master
device transmitting the Poll_Data frame
3.1.15
TP1 polling slave
Poll_Data slave
device transmitting a Poll_Data character
3.1.16
TP1 router
acknowledges frames on data link layer and transmits the received frame on the other side of the router,
provided the device associated with the destination address is located on the other side
3.1.17
TP1 sub-line
outer lines of a zone
3.1.18
TP1 zone
16 TP1 lines can be connected to a zone by using 15 routers
3.2 Abbreviations
AC alternating current
ACK acknowledge
APDU application layer protocol data unit
AT address type
CSMA/CA carrier sense, multiple access with collision avoidance
CKS checksum
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DA destination address
DC direct current
DL TP data link layer type twisted pair
DPS distributed power supply
CTRL control field
HBES Class 1 refers to simple control and command
HBES Class 2 refers to class 1 plus simple voice and stable picture transmission
HBES Class 3 refers to class 2 plus complex video transfers
IFT inter-frame-time
LC line coupler
LN length
LPDU link layer protocol data unit
LSDU link layer service data unit
LTE-HEE logical tag extended hee
MAU medium attachment unit
NACK negative acknowledge
NPCI network layer protocol control information
NRZ non-return-to-zero
OCP over-current protection
PELV protective extra low voltage
PDU protocol data unit
PSU power supply unit
RPD remote powered bus devices
RUP reverse polarity protection
SA source address
SDU service data unit
SELV safety extra low voltage
TP twisted pair
TPDU transport layer protocol data unit
UART universal asynchronous receiver transmitter
up power up
4 Requirements for HBES Class 1, Twisted Pair Type 1 (TP1-64 and TP1-256)
4.1 Physical layer requirements – Overview
The Physical Layers described in this clause are called Physical Layer type twisted pair TP1-64 and
twisted pair TP1-256. The main differences are shown in Table 1. TP1-256 is backwards compatible
towards TP1-64. If common features of TP1-64 and TP1-256 are described, only the expression TP1 is
used.
The Twisted Pair medium TP1 characteristics are:
— data and power transmission with one pair of wires;
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— asynchronous character-oriented data transfer;
— half duplex bi-directional communication;
— a specifically balanced/symmetric base-band signal coding under SELV conditions.
All characteristics given in the following subclauses, for instance maximum number of devices or possible
cable length per physical segment are only valid for cable complying to the requirements as shown in 4.4
)
2
and for TP1 devices of which bus power consumption does not exceed 12 mA .
Table 1 — System parameters of physical layer Type TP1–64 and TP1–256
Characteristics Description TP1–64 Description TP1–256
Medium a
Shielded twisted pair
Topology Linear, star, tree or mixed
Baud rate 9 600 bps
Device supplying Normal: bus powered devices - optional: remote powered
devices
Device power consumption 3 mA to 12 mA
Power Supply Unit (PSU) DC 30 V
Number of PSUs per physical Maximum 2
segment
Number of connectable devices per Maximum 64 Maximum 256
physical segment
Number of addressable devices per b Maximum 255
Maximum 255
physical segment
Total cable length per physical Maximum 1 000 m
segment
Distance between two devices Maximum 700 m
Total number of devices in a network More than 65 000 (with More than 65 000
bridges)
Protection against shock SELV (Safety Extra Low Voltage)
Physical signal Balanced/symmetric baseband signal encoding
a
The shield is not mandatory, shielded cables with earth connection can improve noise immunity.
b
In TP1–64 a physical segment can be extended with up to 3 extra physical segments, each connected to it via a
bridge. Every physical segment can contain 63 devices.
Figure 1 shows the logical structure of the physical layer type TP1 entity. Every device includes one;
every router and bridge is equipped with two such physical layer type TP1 entities.
The physical layer type TP1 entity consists of four blocks:
— cable (medium);
— connector, connecting a device or a bridge to the transmission medium;
— a Medium Attachment Unit (MAU);
———————
2)
Fan-in model allowing devices of which the bus power consumption is higher is under consideration.
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— logical unit.
Figure 1 — Logical structure of physical layer type TP1
Figure 2 shows the relationship between the bits of an octet and the Universal Asynchronous Receiver
Transmitter (UART) character data bits.
Figure 2 — Octet mapped to a serial character
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4.2 Requirements for analogue bus signals
4.2.1 General
In the underneath description, U is an internal reference voltage for the DC part of the bus voltage,
REF
used by the transmitter/receiver for evaluating the sent/received signal levels. This reference voltage is
sampled before the start bit of a byte. This U may vary with the values given in 4.2.5.
REF
The underneath specifications classify a 0 and 1 signal on the bus: the requirements for signal generation
and extraction for the transmitter and receiver respectively are defined in 4.3.2.6 and 4.3.2.7.
4.2.2 Specification of logical “1”
A logical “1” shall be regarded as the idle state of the bus, which means that the transmitter of a MAU
shall be disabled during sending a “1”. The analogue signal at the bus consists normally only of the DC-
part. There is no difference between sending a “1” and sending nothing. A decline of voltage during a “1”
may occur, if a ‘0 bit’ was preceding. The graph shall be within the shaded areas of Figure 3.
Figure 3 — “1”-Bit frame
The characteristics of a logical 1 signal shall follow the values given in Table 2.
Table 2 — Analogue and digital signal of a logical “1”
Parameter Value
Bit-time 104 µs
Voltage (DC-part) 21 to 32 V DC
Slopes (AC-part) Maximum 400 mV/ms
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4.2.3 Specification of logical “0” (Single)
A logical “0” shall be a defined voltage drop (U ) of the analogue bus signal with a duration of t (see
a active
Figure 4). During the following equalization time the voltage may be higher than the DC-part to enable
recharging of energy consumed during the active part. The graph shall be within the shaded areas of
Figure 4.
Figure 4 — “0”-Bit frame
The characteristics of a logical “0” signal shall follow the values given in Table 3.
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Table 3 — Analogue and digital signal of logical “0”
Parameter / Point Minimum Maximum
Bit-time 104 µs (typical)
t 35 µs (typical)
active
t (time between Ua > A and Ua > B) 25 µs 70 µs
s
(see also 0)
Time (Point D - E) 50 µs
Voltage (DC-part) 21 V 32 V
Voltage Ua (Point A) compared to Ref - 0,7 V - 10,5 V
Voltage Ua (Point B) compared to Ref - 0,1 V - 10,5 V
Voltage Ue (Point C - D) compared to Ref 0 V + 13 V
Voltage Uend (Point F) compared to Ref - 0,35 V + 1,8 V
4.2.4 Specification of logical “0” (overlapping)
Overlapping means, that a logical “0” is transmitted at the same time by several devices (e.g. common
ACK). Owing to the propagation delay of the bus cable (PhL-Medium) a time shift of logical zeros can
occur, if sending devices are located at a distance from the receiving devices. The MAU and the Logical
Unit shall be able to detect and interpret these signals. Figure 5 shows an example of two mixed logical
“0” that have a delay (td) of about 10 µs. Assuming that the point of measuring is at device A, the signal of
device B appears after 10 µs with a lower signal amplitude than device A, as it has been damped along
the bus cable.
Figure 5 — Delayed logical “0”
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Figure 6 — Overlapping of two logical “0” (example)
The receiver of the MAU converts this mixed analogue signal to a digital signal. This digital signal differs
from that of a normal “0”, because the width of the receiver’s output pulse is the sum of t + td.
active
However, it is possible, that the receiver’s output delivers a gap at the end of t (See shaded area in
active
Figure 6.) This behaviour requires dedicated decoding software that is able to decode such effects.
4.2.5 Analogue requirements within a transmitted character
4.2.2 and 4.2.3 describe the voltage shape and timing when transmitting a single logical bit. When
transmitting an entire character (consists of a series of bits), the additional requirements of Table 4 shall
be met. The values Ua* and Ue* are referred to Uref at the beginning of the active part of the first bit of
the transmitted character.
Table 4 — Limits within a character
Parameter Value
Ua* Maximum - 10,5 V
Ue* Maximum 11,5 V
Uref (any bit) Maximum - 1 V / + 3 V
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4.2.6 Simultaneous sending / collision behaviour
Although devices shall investigate the bus line before they begin sending, it is possible that two or more
devices send simultaneously. Simultaneous sending of a character occurs when two or more devices
simultaneously transmit ACK, Negative Acknowledgement (NACK) or BUSY messages.
Simultaneous transmission of a logical “0” and a logical “1” will result in a logical “0”.
Simultaneous sending of logical “0” by several devices will result in a signal that is nearly identical to that
of a single transmitting device, as signals are coded in the baseband.
This common signal shall therefore also comply with the values given in Table 2.
If a sending device detects that its own logical “1” was overwritten by another logical “0”, transmission
shall be disabled after this bit. Receiver of both devices shall however remain active.
This behaviour of the physical layer allows a CSMA/CA medium access in data link layer (see 4.8).
4.3 Medium attachment unit (MAU)
4.3.1 General
The medium attachment unit (MAU) shall split the analogue signal of the medium into the DC part and the
serial bit stream. Vice versa the serial bit stream shall be converted to the analogue bus signal.
The DC-part may be used internally to supply the device with power by using a DC/DC converter or
voltage regulator. A wrongly connected MAU shall neither damage the device nor influence the bus
communication.
4.3.2 Requirements within a physical segment
4.3.2.1 General
Within a physical segment the following principal requirements shall be met:
— in an installed system the DC voltage at every device shall be at least 21 V. Devices shall continue to
operate with a DC voltage down to 20 V. The difference between 20 V and 21 V has been laid down
as a reserve;
— the propagation delay of the serial bit stream at the MAU shall be short enough to allow bit-wise
CSMA/CA arbitration during a bit time. The total delay (MAU - Cable - MAU) shall not exceed 12 µs.
Refer also to 4.8.3;
— the Power Supply Unit [PSU(s)] connected to a physical segment shall provide the necessary
effective current required by the devices connected to the physical segment;
SELV requirements shall be met according to EN 50090-2-2.
4.3.2.2 Power up behaviour
Powering up means, that either a single bus device is installed in a ‘running’ bus segment or a PSU is
switched on in a fully equipped bus segment. The rising of the bus voltage is different. Power up
behaviour can be divided into two steps:
— during Start-up, the internal capacitors are being charged with a current limitation;
— during Operation, the capacitors are charged, voltages are constant.
Power up behaviour requires, that
— bus devices run up properly regardless the installed (allowed) topology, when the associated
segment is powered on by the PSU (slow ramp);
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— a single bus device runs up properly if installed in an operating bus segment. Other bus devices
already installed in this segment shall not suffer a ‘reset’ owing to the installation of this additional
bus device (steep ramp);
— a possible signal disturbance, caused by the installation of a single bus device in an operating
segment shall not exceed 20 ms, in order to avoid telegram losses.
4.3.2.3 Power down behaviour
The Power down behaviour occurs when the input to the power converter of the device breaks down. This
input can either be the DC part of the bus voltage or a remote power source (see 4.3.3).
The Power Down behaviour can be divided into three steps:
— during Operation, the capacitors are charged, voltages are constant;
— during hold-up, the Capacitors are discharged;
— during Idle, the power converter draws only a leakage current.
When passing from operation to hold-up, the physical layer may generate a U signal:
save
— to allow devices to backup data before power breaks down,
— to disable further transmission of telegrams by the bus device.
For bus powered devices, this U signal shall be generated when the bus voltage drops below
save
maximal 20 V, thereby taking into account a hysteresis of at least 1 V.
The physical layer shall generate a Reset Signal U when the correct functioning of the power
reset
converter can no longer be ensure
...
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