Landis+Gyr CU-B1 User manual

Communication
Industrial and Commercial
CU-B1, B2, B4
E65C
User Manual
Date: 18.04.2016
File name: D000011142 E65C CU-Bx User Manual en k.docx
© Landis+Gyr D000011142 en
k

2/30 Revision history
© Landis+Gyr D000011142 en k – E65C CU-B1, B2, B4 – User Manual
Revision history
Version Date Comments
– 12.03.2001 First edition
a 19.09.2001 Modifications to face plate, RS232, RS485 interface, applications
b 27.02.2002
Technical Data 1.2 Pulse length 30 ms
c 22.03.2002 Pin allocation of RS 485 corrected
d 16.09.2002 Version CU-B3 cancelled
e 31.01.2003 New layout L+G
f 06.07.2005 Old phone no. replaced by new one
g 16.04.2009 New RS485 installation note
h 07.11.2011 Layout adaptation
k 18.04.2016 Updated disclaimer.
Additional warning information based on standards.
Updated company name.
A
lthough the information contained within this document are presented in good faith and believed to be correct, Landis+Gyr (including its
affiliates, agents and employees) disclaim any and all liability for any errors, inaccuracies or incompleteness relating to the product.
Landis+Gyr makes no warranty, representation or guarantee regarding the performance, quality, durability or suitability of the products for
any particular purpose. To the fullest extent permitted by law Landis+Gyr disclaims (1) any and all liability arising out of the use of the
product, (2) any and all liability, including, but without limitation to, special, consequential and indirect damages and losses, and (3) any and
all implied warranties, including, but without limitation to, fitness for purpose and merchantability.
The information contained in this document is strictly confidential and is intended for the addressee only. The unauthorised use, disclosure,
copying, alteration or distribution of this document or the contents thereof is strictly prohibited and may be unlawful.
A
ll product information are subject to change without notice.

Table of contents 3/30
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Table of contents
Revision history......................................................................................................................................2
Table of contents ...................................................................................................................................3
About this document..............................................................................................................................4
1Device description........................................................................................................................5
1.1 Review......................................................................................................................................5
1.1.1 General view .......................................................................................................................5
1.1.2 Purpose of use....................................................................................................................5
1.1.3 Type designation.................................................................................................................5
1.2 Technical data...........................................................................................................................6
1.2.1 Inputs and outputs...............................................................................................................6
1.2.2 External influences..............................................................................................................7
1.2.3 Weight and dimensions.......................................................................................................7
1.2.4 Connections ........................................................................................................................7
1.2.5 Connection diagram ............................................................................................................8
2Safety...........................................................................................................................................10
2.1 Safety information...................................................................................................................10
2.2 Responsibilities.......................................................................................................................10
2.3 Safety regulations...................................................................................................................11
3Mechanical construction ...........................................................................................................12
4Function ......................................................................................................................................14
4.1 Pulse inputs (S0 interfaces)....................................................................................................14
4.2 RS485 interface......................................................................................................................14
4.3 RS232 interface......................................................................................................................15
4.3.1 Receive and transmit times...............................................................................................15
4.3.2 Function of LEDs...............................................................................................................16
4.4 Application of interfaces..........................................................................................................17
5Installation and commissioning................................................................................................19
5.1 Introduction.............................................................................................................................19
5.2 Material and tools required .....................................................................................................19
5.3 Fitting the communication unit CU-Bx.....................................................................................20
5.4 Connecting the communication unit CU-Bx ............................................................................21
5.4.1 Connecting the signal inputs .............................................................................................22
5.4.2 Connecting the communication interfaces.........................................................................23
5.4.3 Pin allocation RS232.........................................................................................................23
5.4.4 Connecting the RS485 interface........................................................................................24
5.5 Commissioning and functional check......................................................................................25
6Measures in event of faults .......................................................................................................26
6.1 Removing the communication unit CU-Bx ..............................................................................26
6.2 Repairing the communication unit CU-Bx...............................................................................26
7Decommissioning and disposal................................................................................................27
8Index............................................................................................................................................28

4/30 Device description
© Landis+Gyr D000011142 en k – E65C CU-B1, B2, B4 – User Manual
About this document
The present user manual applies to communication unit CU-Bx with inter-
faces CS / RS232 / S0 for meters ZxDxxxAT/CT.
This user manual supplements the meter operating instructions and is
incomplete without the data contained there.
In addition to operating instructions for the meters, the user manual con-
tains all the information necessary for operation of the CU-Bx communica-
tion unit for the intended purpose. This includes:
Provision of knowledge concerning characteristics, construction and func-
tion of the communication unit CU-Bx
Information about possible dangers, their consequences and measures to
prevent any danger
Details concerning the performance of all work throughout the service life of
the communication unit CU-Bx (installation, commissioning, operation,
maintenance, decommissioning and disposal)
The contents of this user manual are intended for technically qualified per-
sonnel of energy supply companies responsible for the system planning,
installation and commissioning, operation, maintenance, decommissioning
and disposal of the meters.
Users of this manual are familiar from their training with the basic principles
of electrical engineering, in particular with the principles of energy measu-
rement, including circuitry types, connection technology, etc.
This user manual is divided in a logical manner suitable for learning and
application, i.e. the individual sections follow the sequence of information
probably required during the various phases of the service life of the com-
munication unit CU-Bx.
Range of validity
Relating documents
Purpose
Target group
Conditions
Subdivision

Device description 5/30
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1 Device description
1.1 Review
1.1.1 General view
The communication unit CU-Bx is a unit complete in itself with its own plas-
tic case. It can be fitted in and removed from meters ZxDxxxAT/CT without
opening the calibration seal. The spring-loaded terminals for the external
connections are at the bottom, while plug contacts at the rear provide con-
nection to the meter electronics.
Fig. 1 Communication unit CU-Bx, removed
1.1.2 Purpose of use
The communication unit CU-Bx is used to supplement the ZxDxxxAT/CT
meters. It contains an RS485 and an RS232 interface depending on ver-
sion for remote scanning of the meter and two signal inputs (S0 interfaces)
for connecting external signal transmitters.
The RS485 interface can be used for simple remote reading (e.g. with
several meters). The RS232 interface remains free for local use or serves
for the connection of an external communication device (e.g. modem).
With version CU-Bx/+ the RS232 interface provides additional functions,
such as time-window or initializing of the external modem.
Any other use of the communication unit is considered improper.
1.1.3 Type designation
The type designation of this communication unit CU-Bx is added to that of
the meter (see meter operating instructions), but is not shown on the main
face plate of the meter. It is specified directly on the case of the communi-
cation unit and can be seen through the front door of the meter through an
opening on the tariff face plate.
The communication unit CU-Bx is available in the following versions:
Version S01/S02 S1 S2
CU-B1 2 S0 RS232 RS485
CU-B2 RS485 RS485
CU-B4 RS232 RS485
+-+-
23
20 21 22
S01 S02
DC DC
72 620 548-2
Landis+Gyr Dialog CU-B1/+
CON
Rx
Tx
Versions

6/30 Device description
© Landis+Gyr D000011142 en k – E65C CU-B1, B2, B4 – User Manual
1.2 Technical data
1.2.1 Inputs and outputs
Pulse inputs
Type: S0 interface
Application: Version CU-B1
Standard: IEC 61393 / DIN 43864
Operating conditions:
– Rated voltage ...................................................................... 24 V DC
– Max. voltage ....................................................................... 27 V DC
– Condition "On" ................................................. min. 10, max. 27 mA
– Current Condition "Off" ................................................... max. 2 mA
– Pulse length ..........................................................................30 ms
– Max conductor length depending on environment
........................................and connecting cable, normally up to 0.5 m
– Insulation resistance to meter ....................... 4 kVAC / 50 Hz, 1 min
............................................................ (creep distance min. 6.2 mm)
RS485 interface
Type: symmetric, serial, asynchronous, bi-directional
interface
Application: Versions CU-B1, CU-B2, CU-B4
Standard: ISO-8482
Operating conditions:
– Signal condition binary 1 .................. difference voltage < -0,2 V DC
– Signal condition binary 0 ................... difference voltage > 0,2 V DC
– Max. bit rate .................................................................... 38'400 bps
– Max. number of slaves .................................................................. 31
– Max conductor length
............depending on environment and connecting cable up to 300 m
– Insulation resistance to meter ....................... 4 kVAC / 50 Hz, 1 min
............................................................ (creep distance min. 6.2 mm)

Device description 7/30
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RS232 interface
Type: asymmetric, serial, asynchronous, bi-directional
interface
Application: Versions CU-B1, CU-B4
Standard: DIN 66259
Mode of operation: transparent / with additional functions
Operating conditions:
– Rated voltage .................................................................... ±12 V DC
– Max. voltage ...................................................................... ±25 V DC
– Max. bit rate .................................................................... 57'600 bps
– Max conductor length
.............depending on environment and connecting cable up to 15 m
– Insulation resistance to meter ....................... 4 kVAC / 50 Hz, 1 min
............................................................ (creep distance min. 6.2 mm)
1.2.2 External influences
Same as meters (see meter operating instructions).
1.2.3 Weight and dimensions
Weight................................................................................ approx. 80 g
Width .......................................................................................... 65 mm
Height ...................................................................................... 103 mm
Depth ......................................................................................... 38 mm
1.2.4 Connections
Pulse inputs (S0 interface)
Type: screwless spring-loaded terminals
Communication interfaces (RS232 and RS485)
Type: RJ12 plug
S01 S02 RS232 RS485
Pulse inputs
(if present) Communication interfaces
CU-B1/B4
1
6
Pin allocation RS232:
1 CTS
2 TxD
3 GND
4 DTR
5 RxD
6 DSR
Fig. 2 External connections communication unit CU-B1/B4

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© Landis+Gyr D000011142 en k – E65C CU-B1, B2, B4 – User Manual
S01 S02 RS485 RS485
Pulse inputs
(if present) Communication interfaces
CU-B2
1
6
Pin allocation RS485:
1 c (ground)
2 a (data a)
3 b (data b)
4 b
5 a
6 c
Fig. 3 External connections communication unit CU-B2
Connections to meter
Type: 10-pin and 4-pin p.c.b. connector
Fig. 4 Internal connections at rear of communication unit CU-Bx
1.2.5 Connection diagram
DC DC
+-
+ - + -
2320 21 22
S01
S02
DC DC DC DC
+-
65
DSRRxD
RS485
5432
a
b
43
DTR
GND
21
TxDCTS
RS232
61
c
Fig. 5 Connection diagram communication unit CU-B1/B4
CTS: Clear To Send
TxD: Transmitted Data
GND: Signal ground
DTR: Data Terminal Ready
RxD: Received Data
DSR: Data Set Ready
In the transparent RS232 interface, connections CTS, DTR and DSR are
connected to ground (GND) by the software.
4-pin connector
10-pin connector

Device description 9/30
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+ - + -
2320 21 22
S01 S02
DC DC RS485
ba
5432 615432
61
c
DC DC
+-
Fig. 6 Connection diagram communication unit CU-B2
c: Ground
a: Data a
b: Data b

10/30 Safety
© Landis+Gyr D000011142 en k – E65C CU-B1, B2, B4 – User Manual
2 Safety
2.1 Safety information
The following symbols are used to draw your attention to the relevant
danger level, i.e. the severity and probability of any danger, in the individual
sections of this document.
Danger
Identifies an extraordinarily great and immediate danger that could lead to
serious physical injury or death.
Warning
Indicates a potentially hazardous situation that may result in minor physical
injury or material damage. Always consult the User Manual when this
symbol is used on the equipment to find out the nature of the potential
hazards and any actions that must be taken to avoid them.
Note
Indicates general details and other useful information to help you with your
work.
In addition to the danger level, safety information also describes the type
and source of the danger, its possible consequences and measures for
avoiding the danger.
Failure to use the equipment as described in this manual may result in
circumventing the protection afforded by the design of the equipment.
2.2 Responsibilities
The owner of the meters – usually the utility company – is responsible for
assuring that all persons engaged in working with meters, such as service
personnel:
Have read and understood the relevant sections of the user manual.
Are appropriately qualified for the work to be performed.
Strictly observe the safety regulations (laid down in section 2.3) and
the operating instructions as specified in the individual sections.
In particular, the owner of the meters bears responsibility for the protection
of persons, prevention of material damage and the training of personnel.
For this purpose, Landis+Gyr provides training on a variety of products and
solutions. Please contact your local Landis+Gyr representative if interested.

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2.3 Safety regulations
The following safety regulations must be observed at all times:
Changing of the communication unit must only be made on meters not
under voltage.
The meter connections must not be under voltage during installation or
when opening. Contact with live parts is dangerous to life. The relevant
fuses should therefore be removed and kept in a safe place until the
work is completed, so that other persons cannot replace them unno-
ticed.
Local safety regulations must be observed. Installation of the meters
must be performed exclusively by technically qualified and suitably
trained personnel.
Secondary circuits of current transformers must be short-circuited (at
the test terminal block) without fail before opening. The high voltage
produced by the interrupted current transformer is dangerous to life
and destroys the transformer.
Transformers in medium or high voltage systems must be earthed on
one side or at the neutral point on the secondary side. Otherwise they
can be statically charged to a voltage which exceeds the insulation
strength of the meter and is also dangerous to life.
The meters must be held securely during installation. They can cause
injuries if dropped.
Meters which have fallen must not be installed, even if no damage is
apparent. They must be returned for testing to the service and repair
department responsible (or the manufacturer). Internal damage can
result in functional disorders or short-circuits.
The meters must on no account be cleaned with running water or with
high pressure devices. Water penetrating can cause short-circuits.

12/30 Mechanical construction
© Landis+Gyr D000011142 en k – E65C CU-B1, B2, B4 – User Manual
3 Mechanical construction
The communication unit CU-Bx is a unit complete in itself with its own case.
If present, it is fitted under the front door, is therefore secured by a company
seal and can be exchanged or fitted in the field if necessary.
Fig. 7 Communication unit CU-Bx fitted in meter
1 Meter
2 Communication unit CU-Bx
3 Front door
The communication unit CU-Bx has the following connections (see also
section 1.2.4):
1
2
Fig. 8 Connections for communication unit CU-Bx
1 10-pin meter connector
2 4-pin meter connector
3 Interface connecting terminals
1
2
3
+-+-
23
20 21 22
S01 S02
DC DC
72 620 548-2
Landis+Gyr Dialog CU-B1/+
CON
Rx
Tx
1
2
3
+-+-
23
20 21 22
S01 S02
DC DC
72 620 548-2
Landis+Gyr Dialog CU-B1/+
CON
Rx
Tx

Mechanical construction 13/30
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The face plate of the communication unit CU-Bx looks like this:
+ - + -
2320 21 22
S01 S02
DC DC
72 620 548-2
Landis & Gyr Dialog CU-B1/+
1
2
3
5
CON
Rx
Tx
4
Fig 9 Face plate of the communication unit CU-Bx (example CU-B1)
1 Serial number
2 Diagram of pulse inputs (only on CU-B1)
3 /+ and dlms symbol depending on parametrizing
4 Transmit/receive diodes
5 Double protective insulation according to IEC 61010
(second version 2001-2, overvoltage category III)
The face plate can contain other data specific to the country, e.g. warnings,
etc.

14/30 Function
© Landis+Gyr D000011142 en k – E65C CU-B1, B2, B4 – User Manual
4 Function
The various interfaces of the communication unit CU-Bx (S0, RS485 and
RS232) are controlled by a microprocessor in the communication unit CU-
Bx, which communicates with the microprocessor of the meter.
4.1 Pulse inputs (S0 interfaces)
The CU-Bx communication unit can receive pulses from external pulse
generators via pulse inputs and record these in the total energy register or,
if provided, in the data profile. The pulse generators must comply with the
conditions of the S0 interface according to IEC 61393 or DIN 43864.
Status "On"
Status "Off"
tT<
_5 ms tT
tOn tOff
>30 ms
_>30 ms
_
0.9 i
0.5 i
0.1 i
Fig. 10 Pulse specification of S0 interface
The pulse inputs use terminals 20 and 21 (S01) or 22 and 23 (S02) of the
left-hand terminals in the communication unit CU-Bx. See also sections
1.2.4 "Connections" and 1.2.5 "Connection diagram".
The pulses from meters connected via the S0 interfaces are each fed to a
total energy register and – in versions with demand recording – to a P run-
ning register. If the meter has a data profile memory, it can also record the
energy status and/or the mean value of demand P running of the external
meters in the data profile.
4.2 RS485 interface
The serial bi-directional RS485 interface is standardised to ISO-8482. The
RS485 interface is based on the principle of a difference signal for trans-
mitter and receiver and permits the connection of several drivers to the
transmission path. Up to 32 transceivers (transmitters/receivers) can be
connected to one line, so that operation is possible as bus or as local semi-
duplex "multipoint" network.
Several closely situated meters can be connected for example via the
RS485 interface of the CU-Bx with a bus system and then connected
centrally to a modem to perform readouts and parameterising.
Depending on the version the RS485 interface supports only the commu-
nication protocol according to IEC 61107 or the communication according
to IEC 61107 and to DLMS.
Application
Protocol

Function 15/30
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4.3 RS232 interface
The asymmetric, serial, asynchronous bi-directional RS232 interface com-
plies with the standard of DIN 66259. Via the RS232 interface of the com-
munication unit CU-Bx
an external modem can be operated, e.g. for data transfer with a
central, or
a direct connection to the RS232 interface of a computer can be estab-
lished.
Depending on the version the RS232 interface supports only the commu-
nication protocol according to IEC 61107 or the communication according
to IEC 61107 and to DLMS.
The RS232 standard defines various data and control signals (see section
5.4.3 "Pin allocation RS232").
In the "transparent" version the interface only performs the communication
and requires a so-called intelligent external modem for this purpose.
In the version with additional functions the interface controls and monitors
an external modem and can operate with time-windows. It is then depend-
ent on a transparent external modem.
4.3.1 Receive and transmit times
When used in the telephone answering mode TAB, the control centre peri-
odically calls the measuring point to read the data, synchronize the time or
to transmit timer tables or other parameters.
The receive time can be limited for incoming calls in order to operate other
units with the same telephone line.
If the units are connected in parallel with the same telephone line, the num-
ber of ringing tones determines the priority. The modem accepts incoming
calls immediately within the receive time. Outside the receiving time, how-
ever, it does not accept incoming calls at all or only after a large number of
ringing tones.
The time-window determines how and at what times the meter can com-
municate with the control centre for remote reading:
No readiness
The (external) modem is out of service.
Reception at all times, daily, weekly or monthly
In this mode of operation the modem always accepts incoming calls
from the control centre for remote reading or in defined time-windows
according to the form of ringing tones defined under "Modem settings".
Outside this communication window the modem can also accept in-
coming calls following a freely parameterised number of ringing tones.
Protocol
Time-window

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An emergency window can be activated with weekly or monthly communi-
cation windows. The modem opens this emergency window 24 hours after
the regular communication window if no remote reading has taken place
within the regular time-window.
ZxD...AT/CT
Control centre
Access possible at any time (without time-window)
Access possible only during the time-window
no successful call of control
centre during the time-window
second access of control centre during the emergency window
after
24 h
Possibilities of access with or without time-window:
Fig. 11 Summary of access possibilities with or without time-window, with time and
emergency window
Communication between ZxDxxxAT/CT meters and control centre can take
place in the ways illustrated above:
from control centre to meter at any time
from control centre to meter daily, weekly or monthly during a defined
time-window
from control centre to meter daily, weekly or monthly during a defined
time-window with additional emergency window
The emergency window is open to the control centre 24 hours after the
regular time-window, if the meter has not called there during the regular
time-window.
Outside of the time-window the modem accepts no call or only after a large
number of ring signals.
4.3.2 Function of LEDs
Functions of the individual LEDs during normal operation:
This LED has no function in the CU-B2 version (without RS232). In versions
CU-B1 and CU-B4 (with RS232) this LED is continuously lit if there is a
connection between the communication unit and the control centre. Data
exchange can take place.
This LED indicates the reception of characters via the RS232 or RS485
interface. The characters are extended by 100 ms. If this LED is flashing, it
indicates reception of the "Ring" function.
This LED indicates the transmission of characters via the RS232 or RS485
interface. The characters are extended by 100 ms.
Emergency window
CON:
Rx:
Tx:

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4.4 Application of interfaces
RS232
Meter with
CU-B1/B4
RS485
ISDN / PSTN / GSM
METCOM etc.
Application 1
Modem
permanent connection
for remote reading
Fig. 12 Example of an application of CU-B1 or B4
In this application the meter is permanently connected to the telephone
network via its RS232 interface and the modem connected.
Application 2
etc.
ISDN / PSTN / GSM
METCOM etc.
Modem
permanent connection
for remote reading
RS232
Meter with
CU-B1/B4
RS485
RS485
Meter with
CU-B2
RS485
Meter with
CU-B2
RS485
RS485
Fig. 13 Example of an application of CU-B1/B4 as master together with CU-B2 as
slaves
This application permits several (up to 31) ZxDxxxAT/CT meters to be con-
nected with one communication unit CU-B2 as slaves to one meter with
communication unit CU-B1 or CU-B4 as master. The two terminals of the
RS485 interface are looped internally (see also Fig. 6) and serve as con-
nections from one meter to the next as shown above.
Communication with all meters takes place via the master, i.e. via its
RS232 interface. This can be connected by the user to a PC or laptop to
perform temporary operations such as service functions or re-parametriz-
ation. It serves on the other hand as fixed connection to a communication
network via an ISDN, PSTN, GSM modem, etc.
Single application
Multiple application

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Application 3
etc.
ISDN / PSTN / GSM
METCOM etc.
Modem
permanent connection
for remote reading free for local
(temporary)
connection to
laptop / PC
RS232
Meter with
CU-B1/B4
RS485
RS232
Meter with
CU-B1/B4
RS485 RS232
Meter with
CU-B1/B4
RS485
Fig. 14 Example of an application of several CU-B1/B4
As in the first example, several (up to 32) ZxDxxxAT/CT meters can be
connected via the RS485 interface for common readout. The difference to
application 1, however, is that all communication units have a free RS232
interface, which can serve for temporary service functions or fixed commu-
nication.

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5 Installation and commissioning
Connection to electrcal installations
Dangers can arise from live electrical installations to which the meters are
connected. Touching live parts is dangerous to life. All safety information
should therefore be strictly observed without fail.
5.1 Introduction
The following personal and technical conditions must be fulfilled for instal-
lation and commissioning of the communication unit CU-Bx:
The work described below must only be performed by technically quali-
fied and suitably trained persons.
These persons must be familiar with and observe the normal local
safety regulations.
Strictly observe the details in section 2 "Safety", in particular the safety
regulations, as well as all information concerning safe operation in this
section.
Before starting work check that the material and tools required are all
present (as in section 5.2).
5.2 Material and tools required
The following material and tools are required for installation of the commu-
nication unit CU-Bx:
Correct communication unit CU-Bx (according to type designation)
Correct connection diagram
Meter (without communication unit CU-Bx) normally already installed
and in service
Company seals
Size 1 screwdriver for screwless spring-loaded terminals
Sealing pliers for company own seals
Phase tester or universal measuring instrument
Possibly buzzer

20/30 Installation and commissioning
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5.3 Fitting the communication unit CU-Bx
No voltage on meter
There must be no voltage applied to the meter when fitting the communica-
tion unit CU-Bx. Contact with live parts is dangerous to life. Disconnect the
meter from the power supply as described in the meter operating instruc-
tions.
The communication unit CU-Bx should be fitted in the meter as follows:
1. Ensure that no voltage is applied to the meter.
2. Remove the company seals on the front door and terminal cover.
3. Open the front door and remove the terminal cover.
Fig. 15 Meter prepared for fitting communication unit CU-Bx
4. Remove the built-in "dummy" communication unit.