Landis+Gyr E650 Series User manual

Electricity Meters IEC/MID
Industrial and Commercial
ZMD300AT/CT
E650 Series 3
User Manual
Date: 29.10.2013
File name: D000030108 E650 ZMD300xT Series 3 User Manual en m.docx
© Landis+Gyr D000030108 en m

2/84 Revision history
© Landis+Gyr D000030108 en m – E650 Series 3 – ZMD300AT/CT – User Manual
Revision history
Version Date Comments
a 01.07.2009 First edition
b 15.10.2009 Corrections to type designation table in section 1.3
Incorrect note on ZMD/ZFD meters removed from section 1.4
Fig. 4.11 replaced
Referenced documents corrected in section 1.8
Error code F.F 00 00 2x 00 added in section 6.2.2 Error Groups
Various grammatical and language errors corrected throughout the document
c 12.11.2009 Minor formatting and typing errors corrected
d 03.12.2009 Minor formatting and typing errors corrected
e 01.06.2010 Update for firmware version B31
f 08.11.2010 Information concerning losses removed
g 27.01.2011 Updated document template and section 1.3 table entry "045x 4 outputs, additional
power supply 100-240 VAC/VDC"
Optional red LED added to outputs in section 1.4
ZFD400 column removed from the table in section 1.5.3
Footnote added after table in section 1.5.3
Reactive energy section modified in section 1.5.4
Summation channels section modified in section 1.5.4
Section 3.1 retitled "Housing"
h 05.10.2011 Updated document template. Comment regarding grounding inserted in section
4.1.2. Section 5.3.3 "Index System" simplified and new section 11 "Appendix OBIS
Code" inserted.
k 26.09.2012 Update for firmware version B32. New extension board 326x. New measured
quantities. New events. New integrated terminal cover switch. Updated document
template. Section "Safety" becomes first section. OBIS explanation expanded. New
representation of value change procedure in set mode. Minor text improvements
and corrections of formatting and typing errors.
m 29.10.2013 Synchronised document version indicators across all languages.
Updated disclaimer.
Reformatted warnings, cautions and notes.
Corrected minor terminology, spelling and punctuation errors.
Added extension board 047x to section 2.3 “Type designation”.
Added information on 3-phase, 3-wire (no neutral) connections to section 3.4
“Connection diagrams (examples)”.
Added extension board 0470 to section 3.4 “Connection diagrams (examples)”.
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 3/84
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Table of contents
Revision history...................................................................................................................................... 2
Table of contents ................................................................................................................................... 3
About this document .............................................................................................................................. 5
1Safety............................................................................................................................................. 6
1.1 Safety information ..................................................................................................................... 6
1.2 Responsibilities ......................................................................................................................... 6
1.3 Safety regulations ..................................................................................................................... 7
1.4 Radio Interference .................................................................................................................... 7
2Device description........................................................................................................................ 8
2.1 Field of application .................................................................................................................... 8
2.2 Characteristics .......................................................................................................................... 8
2.3 Type designation..................................................................................................................... 10
2.4 Block schematic diagram ........................................................................................................ 11
2.5 Measuring system................................................................................................................... 14
2.5.1 Input signals ...................................................................................................................... 14
2.5.2 Signal processor................................................................................................................ 15
2.5.3 Measured quantities .......................................................................................................... 17
2.5.4 Formation of measured quantities..................................................................................... 18
2.5.5 Summation channels......................................................................................................... 22
2.6 Data profile.............................................................................................................................. 22
2.6.1 Stored value profile ........................................................................................................... 23
2.6.2 Load profile 1 and load profile 2 (option)........................................................................... 23
2.6.3 Event log ........................................................................................................................... 23
2.7 Communication ....................................................................................................................... 26
2.7.1 Optical interface ................................................................................................................ 26
2.7.2 Communication units......................................................................................................... 26
2.8 MAP software tools ................................................................................................................. 27
2.9 Anti-tampering features........................................................................................................... 28
2.9.1 DC magnet detection......................................................................................................... 29
2.9.2 Terminal cover detection ................................................................................................... 29
3Mechanical construction ........................................................................................................... 30
3.1 Housing................................................................................................................................... 30
3.2 Faceplates .............................................................................................................................. 33
3.3 Connections ............................................................................................................................ 34
3.4 Connection diagrams (examples) ........................................................................................... 35
3.5 Dimensions ............................................................................................................................. 39
4Installation and uninstallation................................................................................................... 40
4.1 Basic information for connecting meter................................................................................... 40
4.1.1 Connection with 3 phases and neutral .............................................................................. 40
4.1.2 Connection with 3 phases without neutral (Aron circuit).................................................... 40
4.2 Mounting the meter ................................................................................................................. 40
4.3 Connecting meter.................................................................................................................... 42
4.3.1 Connecting the RS485 interface........................................................................................ 45
4.4 Check of connections.............................................................................................................. 46
4.5 Commissioning, functional check and sealing ........................................................................ 46
4.6 Installation of terminal cover detection.................................................................................... 47
4.7 Uninstallation .......................................................................................................................... 48
5Operation..................................................................................................................................... 50

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5.1 Operation with auxiliary power supply .....................................................................................50
5.2 Control elements .....................................................................................................................50
5.2.1 Display buttons ..................................................................................................................50
5.2.2 Control of display via optical interface................................................................................51
5.2.3 Reset button.......................................................................................................................51
5.3 Display.....................................................................................................................................52
5.3.1 Introduction ........................................................................................................................52
5.3.2 Basic layout........................................................................................................................52
5.3.3 Index system......................................................................................................................53
5.4 Types of display.......................................................................................................................54
5.4.1 Operating display ...............................................................................................................54
5.4.2 Display menu .....................................................................................................................55
5.4.3 Service menu .....................................................................................................................58
5.5 Alert LED .................................................................................................................................59
5.6 Optical test output....................................................................................................................59
5.7 Data readout............................................................................................................................60
5.7.1 Readout to IEC 62056-21 ..................................................................................................60
5.7.2 Readout to DLMS...............................................................................................................62
5.8 Input of formatted commands..................................................................................................63
5.9 Set time and date, ID numbers, battery time ...........................................................................64
6Service .........................................................................................................................................65
6.1 Operating faults .......................................................................................................................65
6.2 Error messages .......................................................................................................................65
6.2.1 Structure of an error message ...........................................................................................66
6.2.2 Error groups .......................................................................................................................66
6.3 Repairing meters .....................................................................................................................71
7Maintenance ................................................................................................................................72
7.1 Meter testing............................................................................................................................72
7.1.1 Test mode ..........................................................................................................................72
7.1.2 Measuring times.................................................................................................................72
7.1.3 Optical test output ..............................................................................................................73
7.1.4 No-load test........................................................................................................................74
7.1.5 Starting test active part ......................................................................................................74
7.1.6 Starting test reactive part ...................................................................................................75
7.2 Changing the battery ...............................................................................................................
75
8Disposal .......................................................................................................................................77
9Index.............................................................................................................................................78
Appendix 1 OBIS code ..................................................................................................................81

About this document 5/84
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About this document
The present user manual applies to the meters specified on the title page.
The user manual contains all the information required for metering
applications for the intended purpose. This includes:
Provision of knowledge concerning the characteristics, construction
and function of the meters
Information about potential dangers, their consequences and
measures to prevent any danger
Details about the performance of all activities throughout the service
life of the meters (parameterisation, installation, commissioning,
operation, maintenance, decommissioning and disposal)
The content of this user manual is intended for technically qualified
personnel of utilities (energy supply companies), responsible for system
planning, installation and commissioning, operation, maintenance,
decommissioning and disposal of meters.
The following documents provide further information related to the subject
of this document:
D000030104 "E650 ZMD300AT/CT Series 3 Technical Data"
D000030112 "E650 ZxD Series 3 Functional Description"
The structure and significance of meter type designations are described in
section 2.3 "Type designation". The following conventions are employed in
this user manual for representing type designations:
The lower case letter "x" can be used as an unknown to indicate
different versions (e.g. ZMD310xT for the ZMD310AT and ZMD310CT
meters).
The following collective terms are also sometimes used instead of the
type designation:
– "Active energy meters" for the ZMD300AT meters
– "Combi-meters" for the ZMD300CT meters
Range of validity
Purpose
Target group
Reference documents
Conventions

6/84 Safety
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1 Safety
This section describes the safety information used in this manual, outlines
the responsibilities and lists the safety regulations to be observed.
1.1 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.
Warning
Used to indicate a dangerous situation that could cause bodily injury or
death.
Caution
Used to indicate a situation/ action that could result in material damage or
loss of data.
Note
Used to indicate general guidelines and other useful information.
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.
1.2 Responsibilities
The owner of the meters – usually the utility company – is responsible for
ensuring that all persons working with meters:
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 1.3) 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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1.3 Safety regulations
The following safety regulations must be observed at all times:
The meter connections must be disconnected from all voltage sources
during installation or when opening.
Contact with live parts can be fatal. The relevant supply fuses should,
therefore, be removed and kept in a safe place until the work is
completed so that other persons cannot replace them unnoticed.
Local safety regulations must be observed. Only technically qualified
and appropriately trained personnel are authorised to install the
meters.
Only appropriate tools shall be used for the job. This means, e.g. that
the screwdriver must be of the correct size for the screws, and the
handle of the screwdriver must be insulated.
The meters must be held securely during installation. They can cause
injuries if dropped.
Meters that have been dropped must not be installed, even if no
damage is apparent, but must be returned to the service and repair
department (or the manufacturer) for testing. Internal damage may
result in malfunctions or short-circuits.
The meters must never be cleaned under running water or with
compressed air. Water ingress can cause short-circuits.
1.4 Radio Interference

Possible radio interference in residential environments
This meter is normally a class B product. In combination with some
communication modules it can become a Class A product. In a domestic
environment, this may then cause radio interference, in which case the user
may be required to take adequate measures.

8/84 Device description
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2 Device description
This section provides you with a brief overview of the design and function of
the E650 ZMD300AT/CT meters.
2.1 Field of application
ZMD300xT meters can be used for direct connection at the low voltage
level. They are primarily used by medium consumers.
ZMD300xT meters have a comprehensive tariff structure. This extends
from seasonal tariffs to multiple energy and demand tariff rates.
The ZMD300CT combi-meters record active and reactive energy
consumption, the ZMD300AT active energy meters only the active energy
in three-phase four-wire networks on low voltage, and from this determine
the required electrical measured quantities. They are connected directly to
the phase conductors at the measuring point.
The data determined are displayed (LCD) and are also available at the
optical interface for data acquisition, with an appropriate communication
unit also as required via CS, RS232, RS485, PSTN modem, GSM modem,
etc. When equipped with transmitting contacts, the meters can also be
used as transmitting meters for telemetering. The tariff rates can be
controlled internally or externally.
With a communication unit, the meters can also be used for recording
counter pulses for other physical media (e.g. water or gas volumes).
2.2 Characteristics
ZMD300xT meters have the following basic characteristics:
Recording of active, reactive and apparent energy in all four quadrants
(ZMD300CT) or recording of imported and exported active energy
(ZxD 300AT)
Tariff system with energy and demand tariff rates, stored values, load
profiles, etc.
Extended functions such as monitoring functions, sliding maximum
demand, etc. (for ZMD300CT additionally power factor cosφ)
Tariff control
– External
- via control inputs (ZMD300xT21 and ZMD300xT41)
- via communication interfaces using formatted commands
– Internal
- by integral time switch (ZMD300xT24 and ZMD300xT44)
- by event signals based on monitored values, such as voltage,
current demand, etc.
Display of data on a liquid crystal display (LCD)
Active and reactive power per phase and true RMS values of voltages
and currents by means of digital signal processing (DSP) chips
Accuracy: Compliance with IEC class 1 and with MID accuracy class B
for active energy consumption (ZMD310xT) and IEC class 1 for
reactive energy (ZMD310CT).

Device description 9/84
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Flexible measuring system through parameterisation (definition of
different variables by software)
Correct measurement even with failure of individual phases, or when
used in two- or single-phase networks
Wide range of measurement from starting current to maximum current
Optical interface according to IEC 62056-21 and DLMS
– For direct readout of meter data
– For service functions of the meter, extension board and
communication unit (e.g. parameterisation)
Inputs for recording fixed valency pulses (communication unit)
Output contacts (solid-state relays) for fixed valency pulses, control
signals and status messages
Output contacts (relays) for control and status messages
Installation aids
– Indication of phase voltages, phase angles, rotating field and
direction of energy
Storage of event information, e.g. voltage failures, exceeding of
thresholds or error messages. Event information can be read out via
the available interfaces. Important events can be communicated to the
energy supply company as operational messages (sending of SMS
messages, control of an arrow in the display, drive for an output
contact, etc.).
Interfaces such as CS, RS232, RS485, modem, etc. for remote trans-
mission of data (communication unit)
Auxiliary power supply for communication with the meter if no
measuring voltage is present

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2.3 Type designation
ZMD 3 10 C T 44 4207 S3
Network type
ZMD 3-phase, 4-wire network (M-circuit)
Connection type
3: Direct connection
Accuracy class
10: Active energy class 1 (IEC), B (MID)
Measured quantities
C:
A:
Active and reactive energy
Active energy
Construction
T: With exchangeable communication units
Tariffication
21:
24:
41:
44:
Energy rates, external rate control via control inputs
Energy rates, internal rate control via time switch
(additionally possible via control inputs)
Energy and demand rates, external rate control via control inputs
Energy and demand rates, internal rate control via time switch
(additionally possible via control inputs)
All versions with 3 control inputs and 2 output contacts
Additional functions
000x
060x
240x
326x
420x
045x
046x
047x
No extension board
6 outputs
2 control inputs, 4 outputs
3 control inputs. 2 relays outputs, auxiliary power supply 12–24 VDC
4 control inputs, 2 outputs
4 outputs, auxiliary power supply 100–240 VAC/VDC
4 outputs, auxiliary power supply 12–24 VDC
4 outputs, auxiliary power supply 12–60 VDC
xxx0
xxx2
xxx7
xxx9
No additional functions
DC magnet detection
Load profile
DC magnet detection and load profile (integrated terminal cover switch option only available
in this configuration)
Series 3
The communication unit is not a part of this type designation, since it is a
complete unit in itself. Users can change it at any time without opening the
certification seal. Every communication unit has its own user manual.
The hardware version is distinguished by the series designation. The 1st
hardware generation (Series 1) has no series designation.
The 2nd hardware generation (Series 2) the series designation ‘S2’ is
printed on the nameplate directly after the type designation. With meters
which contain a measurement sensor with embedded coil, the series
designation ‘S2a’ is used for distinction. ‘S2s’ represents a Series 2 meter
with symmetrical terminal layout.
‘S3’ represents the newest hardware generation.
Series designation

Device description 11/84
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The firmware version and firmware checksum stored in the meter can be
shown on the display or read out as IEC readout list, if parameterised
accordingly (see section 5.7 "Data readout"). Specific meter characteristics
are present or not depending on the firmware version.
2.4 Block schematic diagram
This section provides an overview of the function of ZMD300xT meters
based on a block schematic diagram.
Figure 1. Block schematic diagram ZMD300xT
The ZMD300AT active energy meters record the imported and exported
active energy consumption, while the ZMD300CT combi-meters record the
active and reactive energy consumption in all four quadrants.
The ZMD300xT meters can be fitted with modular communication
interfaces in a communication unit, which can be exchanged or used in the
field as required.
The main meter inputs are:
Connections of phase voltages (U1, U2, U3), phase currents (I1, I2, I3)
and neutral conductor (N)
– For processing in the measuring system
– For the three-phase power supply to the meter and voltage monitor
Control inputs Ut(3 fixed, plus up to 4 others on extension board) for:
– Changeover of energy and demand tariff rates
– Resetting
– Demand inhibition
– Synchronising
Opto-couplers protect the internal circuitry from interference, which
could otherwise enter via the control inputs.
Buttons
– For display control (display buttons, optical interface)
– For resetting or service functions (reset button)
Firmware version
Inputs

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Pulse inputs for connection of external pulse transmitters (only for
meters equipped with a communication unit)
The meter has the following outputs:
LCD display with buttons for local reading of billing data (single 8-digit
display with additional information, such as energy direction, energy
type, presence of phase voltages and identification number)
Optical test outputs (red, 1 in active energy meters, 2 in combi-meters)
Optional alert LED (red) to indicate alerts on the front face of the meter
Static relay with freely parameterised signal assignment (2 fixed, plus
up to 6 others on the extension board)
Relay outputs with limited parameterised signal assignment due to
limited life expectancy (up to 2 on the extension board)
Optical interface for automatic local data acquisition by a suitable
acquisition unit (handheld terminal)
Communication interfaces of various kinds in the communication unit
(also see section 2.7 "Communication" )
The input circuits (voltage dividers and current shunts with voltage trans-
former) record voltage and current in the individual phases. Analogue-
digital converters digitise these values and feed them as instantaneous
digital values via calibration stages to a signal processor.
The signal processor determines the following measured quantities from
the instantaneous digital values of voltage and current for each phase and
forms their mean value over one second:
Active power per phase
Reactive power per phase (combi-meters ZMD300CT only)
Phase voltages
Phase currents
Network (mains) frequency
Phase angles
For signal utilisation in the various registers, the microprocessor scans the
measured quantities every second to determine the following values:
Active energy (sum and individual phases, separated according to
energy direction, if required in the combi-meters ZMD300CT also
assigned to the 4 quadrants)
Reactive energy (only for combi-meters ZMD300CT, sum and
individual phases, separated according to energy direction, assigned
to the 4 quadrants)
Apparent energy (only for combi-meters ZMD300CT, sum and
individual phases, separated according to energy direction)
Power factor cosφ(only for combi-meters ZMD300CT, individual
phases and mean value)
Phase voltages
Phase currents and neutral current
Outputs
Measuring system
Signal processing
Signal utilisation

Device description 13/84
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Active and reactive power
Direction of rotating field
Total harmonic distortions of active energy, voltage and current
Rate control is performed:
Externally via control inputs (3 fixed, plus up to 4 others on the
extension board)
Externally via communication interfaces using formatted commands
Internally by time switch and calendar clock
By event signals based on threshold values of the monitoring functions
The following registers are available for evaluation of the individual
measured values:
32 for energy rates
27 for total energy
10 for running mean demand values
24 for demand rates
2 for power factors cosφ(combi-meters ZMD300CT only)
Up to 41 diagnostic registers
Others for values of voltage and current, network frequency and phase
angles
A non-volatile flash memory serves to record data profiles and also
contains the configuration and parameterisation data of the meter and
secures the billing data against loss due to voltage failures.
The supply voltages for the meter electronics are obtained from the three-
phase network, whereby the phase voltage can vary over the entire voltage
range without the supply voltage having to be adjusted. A voltage monitor
ensures correct operation and reliable data recovery in the event of a
power failure and correct restarting when the voltage is restored.
For medium or high-voltage applications in particular, the measuring
voltage can be switched off. Since the meter normally obtains its supply
from the measuring voltage, it is also switched off and cannot be read. The
auxiliary power supply connected in parallel with the normal power supply
ensures operation of the meter free from interruption, so that it can be read
at any time. The auxiliary power supply is situated on an extension board.
The extension board is fitted inside the meter and is secured by the
certification seals. It cannot be exchanged. It can have the following
components:
Up to 4 control inputs in combination with
Up to 6 output contacts (solid-state relays)
Up to 2 relays outputs
An auxiliary power supply
Tariff control
Data preparation for
billing
Memory
Power supply
Auxiliary power
supply
Extension board

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The communication unit for fitting only in the ZMD300xT meters is a
complete unit in its own case. If present, it is situated behind the front door,
and is therefore secured by a utility seal and can be exchanged or inserted
in the field if necessary. It contains:
Communication interfaces as required for remote readout of the meter
(e.g. CS, RS232, RS485, modem)
Two signal inputs (S0 interfaces) for processing external pulse
transmitters
2.5 Measuring system
Figure 2. Block schematic diagram of measuring system
2.5.1 Input signals
The meter has the analogue current values I1, I2 and I3 and analogue
voltage values U1, U2 and U3 available as input signals.
Figure 3. Type of measurement ZMD300xT
Since the ZMD300xT measures the individual phases mutually
independently with one measuring element each, it can record the sum of
the three phases, the individual phases themselves, the phase angle
between voltage and current as well as the angle between voltages U1–U2
and U1–U3.
High resistance voltage dividers reduce the voltages U1, U2 and U3 (58 to
240 V) applied to the meter to a proportionate amount of a few mV (UU) for
further processing.
Internal current transformers reduce the input currents I1, I2 and I3 to the
meter (0 to 10 A) for further processing. The secondary currents of these
current transformers develop voltages proportional to the input currents
across resistors, also of a few mV (UI).
Communication unit
ZMD300xT
Voltage input
Current input

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2.5.2 Signal processor
Figure 4. Principle of signal processor
ZMD300AT active energy meters do not measure reactive energy.
The analogue signals Uxand Ixare digitised in Sigma-Delta converters
(analogue-digital converters with highest resolution) with a sample rate of
1.6 kHz and then filtered. A following calibration stage compensates for the
natural errors of the voltage divider or current transformer, so that no
further adjustment is necessary in the subsequent processing.
Calibrated digital instantaneous values of voltage (u) and current (i) for all
three phases are then available as intermediate values for the formation of
the required values in the signal processor.
The instantaneous value of active power p is produced by multiplying the
instantaneous values of voltage u and current i (the active component
corresponds to the product of voltage component with the current
component parallel to the voltage). Thereby the harmonics up to 1 kHz are
measured correctly.
U
I
I
P
I
Q
P = U I cos
..
Calculation per phase of

Figure 5. Active power calculation
If the meter is parameterised to calculate instantaneous power as signed
values, the following values of power are available:
Active P: + in QI and QIV, - in QII and QIII
Reactive P: + in QI and QII, - in QIII and QIV
There are two possibilities to calculate the instantaneous value of reactive
power (ZxD300Cx combi-meters only):
Measured:
For the instantaneous value of reactive power q the instantaneous value of
voltage u must be rotated by 90° before multiplication (the reactive
Digitizing
Calculation of active
power
Instantaneous power
with sign
Calculation of reactive
power

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component is the product of the voltage component with the current
component vertical to the voltage). Thereby no harmonics are measured
since only the fundamental wave is rotated through 90°.
U
I
I
P
I
Q
Q = U I sin 
..
Calculation per phase of

Figure 6. Reactive power calculation (method: measured)
Calculated vectorial (not recommended):
The instantaneous value of reactive power is calculated using the values of
active power and apparent power.
The reactive power is the square root of the square value of apparent
power minus the square value of active power. This method includes the
harmonics.



The square values of voltage and current are obtained by multiplying the
instantaneous values of voltage and current by themselves. From these
values the signal processor forms the corresponding single-phase RMS
values URMS and IRMS.
The network frequency can be calculated from the time measured between
two zero passages (change from negative to positive value of voltage U1).
The times between zero passage of the phase voltage U1 and those of the
other phase voltages U2 and U3 serves to determine the phase angle
between the voltages and of the rotating field.
U1 U2 U3
1 : T U1-U2
2 : T U1-U3
3 : T (fn)
123
Time measurement
for rotating field,
frequency, phase angle
U1-U1
Figure 7. Time measurement
The phase angle between voltage and current is determined by the times
between zero passage of the phase voltage U1 and those of the phase
currents I1, I2 and I3.
For further processing of the individual signal, the signal processor
generates mean values over one second, which the following
microprocessor scans at intervals of one second.
URMS, IRMS calculation
Time measurement
Mean value formation

Device description 17/84
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2.5.3 Measured quantities
Measured quantity ZMD300
Active energy in quadrant I A (QI) Sum / Phases
Active energy in quadrant II A (QII) Sum / Phases
Active energy in quadrant III A (QIII) Sum / Phases
Active energy in quadrant IV A (QIV) Sum / Phases
Active energy import +A (QI+QIV) Sum / Phases
Active energy export –A (QII+QIII) Sum / Phases
Active energy, absolute value +A+-ASum / Phases
Active energy, absolute value +A--ASum / Phases
Active energy import summation Σ+A Sum
Active energy export summation Σ-A Sum
Active energy by single quantity ΣALxSum
Reactive energy in quadrant I R (QI) Sum / Phases
Reactive energy in quadrant II R (QII) Sum / Phases
Reactive energy in quadrant III R (QIII) Sum / Phases
Reactive energy in quadrant IV R (QIV) Sum / Phases
Reactive energy import +R (QI+QII) Sum / Phases
Reactive energy export –R (QIII+QIV) Sum / Phases
Reactive energy import +R (QI+QIV) Sum / Phases
Reactive energy export –R (QII+QIII) Sum / Phases
Reactive energy, combined R (QI+QIII) Sum / Phases
Reactive energy, combined R (QII+QIV) Sum / Phases
Reactive energy, absolute value +R+-RSum / Phases
Reactive energy, absolute value +R--RSum / Phases
Reactive energy import summation Σ+R Sum
Reactive energy export summation Σ-R Sum
Apparent energy import +S (QI+QIV) Sum / Phases
Apparent energy export -S (QII+QIII) Sum / Phases
Phase voltages (RMS) U1, U2, U3
Phase currents (RMS) I1, I2, I3
Neutral current I0 yes
Network frequency fnyes
Active power ±PSum / Phases
Reactive power ±QSum / Phases
Phase angle between voltages U U1-U2 / U1-U3*
Phase angle between voltage and
current
U-I U1-I1, U1-I2, U1-I3 *
or
U1-I1, U2-I2, U3-I3
Power factor PF Sum / Phases
Direction of rotating field yes

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© Landis+Gyr D000030108 en m – E650 Series 3 – ZMD300AT/CT – User Manual
Measured quantity ZMD300
THD of active energy import +THDASum
THD of active energy export -THDASum
THD of active energy (percent) THDA[%] Sum
THD of phase voltages (absolute) THDUPhase 1, 2, 3
THD of voltage (percent) THDU[%] Sum
THD of phase currents (absolute) THDIPhase 1, 2, 3
THD of current (percent) THDI[%] Sum
* Only if U1 is present.
2.5.4 Formation of measured quantities
By scanning the mean values of active power P, and in combi-meters also
reactive power Q every second, energy components are produced (Ws or
vars) at fixed intervals (every second) and with varying energy magnitudes
or demand. These energy components are scaled by the microprocessor
corresponding to the meter constant and are then available as measured
quantities for selection of the measured values. The measured values are
fed directly to the following registers to record the energy and the maximum
demand (in combi-meters also of minimum power factor).
The active energy in the individual phases ±A1, ±A2 and ±A3 are formed
directly from the mean values of active power P1, P2 and P3.
By summating the mean values of active energy A1, A2 and A3 the
microprocessor calculates the total active energy import +A or the total
active energy export -A.
Measured quantities
Mean values
per second
A1±
3±A
2±A
+A (Import)
-A (Export)

Figure 8. Total active energy
The reactive energy values of the individual phases ±R1, ±R2 and ±R3 are
obtained in the combi-meters directly from the mean values of reactive
power Q1, Q2 and Q3. The reactive energy can therefore also be
calculated vectorially (see 1.5.2).
By summating the mean values of reactive energy R1, R2 and R3, the
microprocessor calculates the total positive reactive energy +R or the total
negative reactive energy -R.
Measured quantities
Mean values
per second
R1±
3±R
2±R
+R
-R

Figure 9. Total reactive energy
Active energy
Reactive energy

Device description 19/84
D000030108 en m – E650 Series 3 – ZMD300AT/CT – User Manual © Landis+Gyr
The microprocessor can allocate the reactive energy to the 4 quadrants in
the combi-meters from the signs of R and A:
Reactive energy in 1st quadrant: +Ri
Reactive energy in 2nd quadrant: +Rc
Reactive energy in 3rd quadrant: –Ri
Reactive energy in 4th quadrant: –Rc
In the same way, it can allocate the reactive energy of the individual phases
to the 4 quadrants.
+R
+ kWh
- kWh
-R
+Ri+Rc
-Rc-Ri
+A ImportExport -A
- kvarh - kvarh
+ kvarh+ kvarh
Quadrant II Quadrant I
Quadrant IVQuadrant III
Figure 10. 4-quadrant measurement
The quadrants are numbered from top right as 1st quadrant (+A/+Ri) anti-
clockwise to the 4th quadrant (+A/–Rc) at bottom right.
The apparent energy is calculated in the combi-meters in two ways:
By vectorial addition of the active and reactive energy of the individual
phases
By multiplying the rms values of voltage and current of the individual
phases
The method of calculation can be parameterised (only one possible in each
case).
From the mean values A1, A2 and A3 and R1, R2 and R3 the
microprocessor calculates the apparent energy of the individual phases
±S1, ±S2 and ±S3 as well as the total apparent energy ±S.
Measured quantities
Mean values
per second
1±A
3±A
2±A
+S (Import)
-S (Export)

R1±
3±R
2±R

(A1 + A2 + A3) + (R1 + R2 + R3)
2
2

Figure 11. Total apparent energy according to calculation method 1
Apparent energy
Calculation method 1
(vectorial addition)

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Only fundamental wave considered for reactive energy
Only the fundamental wave is considered for the calculation of the reactive
energy share; possible harmonics are not taken into account.
From the mean values U1rms, U2rms, U3rms and I1rms, I2rms, I3rms the
microprocessor calculates by multiplication the apparent power of the
individual phases ±VA1, ±VA2 and ±VA3 and summates these for the total
apparent power ±VA.
Measured quantities
Mean values
per second
1
rms
I
+S (Import)
-S (Export)
å

1rms U
1U1
rms rm s
I
2rms I
å
2rms U
2U2
rms rm s
I
3rms I
å
3rms U
3U3
rms rm s
I



Figure 12. Total apparent power according to calculation method 2 (ZxD300Cx
combi-meters only)

Harmonics considered for reactive energy
As RMS values are used for the calculation of the apparent energy with
calculation method 2, not only the fundamental wave but also the
harmonics are taken into account. Therefore, if harmonics are present, the
measured values are greater than those of calculation method 1.
The values of two measurement quantities (incl. pulse inputs EX1 and EX2)
can be added.
The power factor cosφis calculated in combi-meters as follows:
The meter uses the method of calculation employed for calculating the
apparent power.
The rms values of the voltages U1rms, U2rms and U3rms are obtained from
the mean values of the squares of the voltages by extracting the root and
directly from these the phase voltages U1, U2 and U3.
The rms values of the currents I1rms, I2rms and I3rms are obtained from the
mean values of the squares of the currents by extracting the root and
directly from these the phase currents I1, I2 and I3.
The signal processor calculates the instantaneous neutral current i0 by
adding the instantaneous phase currents i1, i2 and i3.
i1
i2
i3
i0
i0 = i1 + i2 + i3
(vectorial addition)
Figure 13. Neutral current I0
Calculation method 2
(from rms values)
Summation channels
Power factor cosφ
Phase voltages
Phase currents
Neutral current