Mega Meg39 User manual

PQ monitor MEg39
User manual
Měřící Energetické Aparáty, a.s.
664 31 Česká 390
Czech Republic

PQ monitor MEg39 – user manual
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PQ monitor MEg39
INTRODUCTION
PQ monitor MEg39 measures four voltage and four current values at LV, MV, HV levels.
It provides the functions of recording, electricity meter and analysis of voltage quality, all
performed simultaneously. In the recording function, PQ monitor MEg39, hereinafter
referred to as the monitor, processes all measured values, evaluates powers, energy and
harmonics up to the order of 64. In the function of class A voltage quality analyser, the
monitor evaluates all parameters for measured three voltages and three currents, as stipu-
lated by the standard. It analyses harmonics and centered subgroups of interharmonics
up to the order of 125. When recording events, the monitor, aside from recording the
course of URMS1/2 and IRMS1/2, makes an oscillographic record of all four values of voltage
and current. e monitor can operate as an oscillograph with the function of recording
the voltage values U1 to U4 and current values I1 to I4 into data memory; an oscillogra-
phic record can be triggered by voltage U4.
e voltage measuring inputs are designed for indirect voltage measurements by means
of instrument transformers for the MV and HV levels and for direct measurements at
the LV level. e current inputs are only designed for indirect measurements by means of
instrument current transformers.
e monitor is supplied by power mains voltage or by DC voltage and it is resistant aga-
inst short-term power outages. e device can be powered by DC 12 V from a separate
UPS supply MEg101.3. is power supply is connected through the HBUS connector
located in the DIN rail on which the device is installed. is bus connector enables con-
necting a communication unit MEg202.3, which enables remote transmission of data
from the device by means of GPRS data service using the GSM mobile network. e
monitor is equipped with four communication interfaces. e serial USB interface is
designed for local parameterization of the device and for downloading of measured data,
the Ethernet and RS485 interfaces are designed for connecting to local technological
networks and the RS232 interface is reserved for service purposes.

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INFORMATION ON SW
PQ monitor MEg39 package includes a CD with user programs. Parameterization of
measurements, reading of measured data, displaying of direct measurements, including
an oscillographic recording, are carried out by the SW PQ program. Unied program
Data Viewer ensures displaying of measured data in graphic and tabular form of a data
le, export of measured data and printing tasks. Functions of the mentioned programs
are described in separate user manuals [1], [2]. e database based program WebDatOr,
supplied separately, is ready to take care of work with data les from one or more measu-
rement instruments, even of dierent types [3].
BASIC INFORMATION ON MONITOR MEg39
PQ monitor MEg39, Fig.1, is designed for xed mounting in LV, MV and HV networks.
e MEg39 unit is installed in a polycarbonate self-extinguishing box with the dimensi-
ons of 108 × 90 × 63 mm with the design for DIN rail mounting. e monitor is installed
under the switchgear box cover with a possibility of sealing to restrict access to the termi-
nals. e instrument panel can be sealed, too. Input terminals of measured voltages and
currents, power supply and communication lines are realized by means of screw termi-
nals for a wire diameter of up to 4 mm2. Measured voltages are led to the corresponding
terminals U1 (36), U2 (34), U3 (32), U4 (30) and N (28). e four yellow LEDs U1, U2,
U3 and U4 signalize by permanent light the presence of input voltages within preset
tolerances. If a measured voltage is beyond preset tolerances, the corresponding LED
ashes shortly, see the description of LED voltage indicators in Table 1. e unit panel
also contains a green LED indicator RUN, signalizing the operation of the MEg39 unit.
Measured currents are led to the pairs of terminals I1 (2,3), I2 (4,5) and I3 (6,7), I4 (8,9)
whilst the current input terminal is marked by a dot.
Supply voltage is connected to the terminals L (16) and N (18).
Two-value input signal is led to the IN (24,25) terminals, the 25 terminal is positive. e
output signal OUT (26,27) is realized by means of the relay contact.
e miniUSB connector located on the panel of the unit is designed for local commu-
nication. Remote communication is realized by means of the RS485 interfaces at the
terminals 22 and 23. Furthermore, it is possible to use the Ethernet interface, whose RJ45
connector is located at the panel of the unit and it enables using the functions provided
by the built-in webserver.

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Fig. 1 – Designation of elements of PQ monitor MEg39 – description in Table 1
238 9
4
5
7
68 10
12
1 2 3 4 5678 9 16 17 18
1
11
Tab. 1: Description of device components
Item Name Description
1 Voltage
inputs
Terminals for connecting signals of the secondary windings of
instrument voltage transformers for the MV and HV levels or for
direct connecting of phase voltages at the LV level.
2 Current
inputs
Terminals for connecting signals of the secondary windings of
instrument current transformers. e input is marked with adot.
3miniUSB
connector
USB 2.0 interface connector for local communication

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Item Name Description
4RJ45
connector
ETHERNET 100BaseTx interface connector for connecting in
local network.
• e green LINK_LED signalizes data line speed
(lit 100 Mbit/s / not lit 10 Mbit/s)
• e orange ACTIVITY_LED light signalizes a data trans-
mission in progress
5 Status
of LED
indicator
RUN
Short ashing – the monitor is performing measurements accor-
ding to the programmed parameterization.
Repeated short ashing – the monitor has been programmed but
is not measuring yet, because the preset time of measurement
start has not come yet or the supply has not switched on due to
programmed measurement with delayed start.
Alternating light 1:1 – oscillographic recording.
6 Status of
measured
voltages
U1, U2,
U3, U4
Signalization of the status of voltage at the inputs U1, U2, U3
and U4 during measurement at the LV level (Y-connection) or
U1-U2, U2-U3, U3-U1 during measurement at the MV and HV
level (delta connection).
Light:
• constant – voltage is within the preset tolerance range
(0.9 Un to 1.1 Un)
• one ash – voltage is within the preset range of interruption
• two ashes – voltage is within the preset range of dip
• three ashes – voltage is the preset range of swell.
7GPS
antenna
connector
Connector for connecting a coaxial cable of antenna for receiving
GPS time synchronization signal.
8DIN rail
lock
Orange locks situated at the top and bottom of the device must
be unlocked for dismantling the device from the DIN rail.
9Power
supply
terminals
Terminals for connecting power supply voltage

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Item Name Description
10 Input and
output
signal
terminals
Terminals for connecting two-state signals and data interfaces
RS485 and RS232.
11 HBUS bus
connector
Bus connector for interconnecting with UPS supply MEg101.3
and communication unit MEg202.3
(HBUS is installed between the device base and DIN rail)
12 Rating
plate
e rating plate contains data valid for the specic version of the
monitor
SAFETY INFORMATION
• is information must be read very carefully.
• Warnings warn of issues representing safety risks to operating personnel.
• Cautions state conditions and issues that could result in damage to the monitor.
Warning
• Attention! Operating personnel performing installation of the device into cir-
cuits with live parts must be equipped with and use during installation perso-
nal protective means and other safety equipment.
• Any use of PQ monitor MEg39 in a way for which it has not been designed
by the manufacturer can impair the protection provided by the PQ monitor
MEg39.
• Personnel performing installation of the device must be qualied for work under and
near hazardous voltage. ey must also be trained in providing rst aid.
• e monitor can only be operated by qualied personnel.
• Maintenance and repairs of the monitors can only be carried out by the manufactu-
rer or service organizations trained by the manufacturer.
• It is not permitted to use any other accessories than those included in supply of
amonitor.

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Caution
e meaning of symbols used in the user manual and in descriptions of the PQ monitor
MEg39:
Note in documentation / Warning, risk of danger
Warning, electric shock hazard
CAT III Overvoltage category, characterizing the state of temporary overvoltage.
Usually for LV installations in buildings, behind electric energy meter
fuses
Safety class II, double or reinforced insulation
IP code Degree of protection by cover
Product is designated for recycling and waste-collecting facilities
Declaration of compliance – European Community
e maximum voltage to the common conductor can be 300 VAC otherwise
there is a risk of damage to the monitor
Fig. 2: Dimensions of the device
89,7
62,2
11,2 11,2
108

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Fig. 3: Design of rating plate for measurements at the MV and HV voltage level
MEg39/cl. A
Made in Czech Republic
U 100V~ P-P, U 300V~ P-N
nmax
n
I 1A, I 1.2A
max
90 230V~ 10%,50Hz, 8VA/4W
+
-
÷
100 300V 10%, 4W
+
-
÷
Explanation to the rating plate
e rating plate of the monitor, see Fig. 3, is located on the left side of the cover. In additi-
on to manufacturer‘s identication data and monitor designation, it includes specication
of power supply voltage range and consumption for the stated power supply voltages.
Voltage inputs:
Measurement at the MV and HV levels are delta U1-U2, U2-U3 and U3-U1 with the
rated value of 100 V, voltage U4 is measured against the N input with the rated voltage
of 100 / √3 V.
e maximum voltage value at the inputs U1, U2, U3 and U4 against N is 300 VAC.
Connected to the current inputs I1, I2, I3 and I4 are the secondary windings of instru-
ment current transformers with the rated current of 1 A.
e measuring range of the current inputs is up to 1.2 In.
MEASURING CONNECTION WITH INSTRUMENT MEASURING
TRANSFORMERS IN A MEASURING CHAIN
In MV and HV networks, measurements are indirect via measuring instrument trans-
formers.
For three-phase voltage measurement it is necessary to connect voltages U1, U2 and U3
in the left rotation direction, at which the device is calibrated.
When measuring is performed at the MV level and the voltage input U4 is not used, it is
recommended to connect this input with the N input.

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Fig. 4: ree-phase measuring of line to line voltages and phase currents in MV and
HV voltage with earthed center
L1
L2
L3
I2
I3
U1
U2
U3
I1
Positive
direction
of energy
flow
(U/100/ )V
3
(U/100/ )V
3
(U/100/ )V
3
118
19
36

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Fig. 5: Measurement of line to line voltages, U0 voltage, phase currents, I0 current
in a compensated MV network
118
19
36
L1
L3
TL
I2
I3
U1
U2
U3
U4
I1
Positive
direction
of energy
flow
(U/100/ )V
3
(U/100/ )V
3
(U/100/ )V
3
(U/100/3)V
L2

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Fig. 6: Measurement of line to line voltages and phase currents in the Aron connection
at the MV network
L1
L2
L3
I3
U1
U2
U3
I1
Positive
direction
of energy
flow
118
19
36

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Fig. 7: Measurement of phase voltages, voltage between neutral conductor and ground
and phase currents including phase currents dierence
118
19
36
I2
I3
I1
Positive
direction
of energy
flow
L1
L3
L2
N
PE

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Fig. 8: ree-phase measurement of voltage and current at the LV output and measure-
ment of phase voltage and current of another LV output
118
19
36
L1
L3
L2
PEN
L1
L3
L2
PEN
Positive
direction
of energy
flow

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Fig. 9: Connection of device terminals
118
19
36
I1 I2 I3 I4
250V/2A
80230VAC, 50Hz
90300VDC
U1 U2 U3 U4 N
15
RS232
~
RS485
max 30V 1A
B
A
GPS
antenna
Tab. 2: Description of the function of MEg39 terminals
Terminal number Function
1 -
2 I1 current input
3 I1 current output
4 I2 current input
5 I2 current output
6 I3 current input
7 I3 current output

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Terminal number Function
8 I4 current input
9 I4 current output
10 -
11 -
12 -
13 -
14 -
15 -
16 L (power supply)
17 -
18 N (power supply)
19 RS232 GND
20 RS232 Tx (DTE)
21 RS232 Rx (DTE)
22 RS485 B (negative idle level of signal)
23 RS485 A (positive idle level of signal)
24 IN_GND
25 IN+
26 OUT
27 OUT
28 N
29 -
30 U4
31 -
32 U3
33 -
34 U2
35 -
36 U1

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MEASURED DATA
e range of measured data depends on connection for measurement and measurement
parameterization. Measured data are divided into data of continuous phenomena of vol-
tage quality, event data and recorder data.
Data of continuous phenomena of voltage quality (aggregation interval 10 min):
- Time of evaluation
- Voltage unbalance
- Frequency
- Voltage magnitude
- Voltage deviations Uover, Uunder
- Flicker Pst and Plt
- THDU
- DC component, fundamental harmonic up to 125th harmonic of voltage
- Centered subgroups of interharmonic component of voltage up to the order of 125
- Level of voltage signals
- Flagged data
- Currents
- Basic to 125th harmonics of currents
- Centered subgroups of interharmonic I up to the order of 125
Data at events :
- Time of event
- Event duration
- Moments when the limits for interruption, dip and swell of voltage and current
are exceeded
- Residual and maximum values of voltage and current
- Curves of voltages URMS1/2 and currents IRMS1/2
- Oscillogram of voltage and current curves during event
- Harmonic voltages and currents during event

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Recorder data (aggregation interval from 1 s to ¼ h pursuant to measuring parameteri-
zation):
- Time of evaluation
- Voltage
- Currents
- Active powers
- Reactive powers
- PF
- THDU
- THDI
- Harmonic components of voltages up to the order of 64.
- Harmonic components of currents up to the order of 64.
- Active and reactive energy (6 registers for each phase)
e above stated data of continuous phenomena of voltage quality are stipulated for the
voltages U1, U2, U3 and currents I1, I2, I3.
e above stated recorded data of events starting from an exceeding of the dened limits
for voltages U1 to U4 and for currents I1 to I3 are recorded for all the stated values.
e above stated recorder data apply to voltages U1 to U4 and currents I1 to I4.

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INSTALLATION OF MONITOR, PREPARATION FOR MEASUREMENT
Connecting of power supply and measuring voltage circuits must be done in volta-
ge-free state.
It is not permitted to connect the voltage inputs to phase voltages higher than 300 VAC
and line to line voltages higher than 520 VAC in CAT III overvoltage category circuits.
Installation of the MEg39 monitor may only be performed by qualied personnel
equipped with personal protective means against electric shock and trained in pro-
viding the rst aid.
Monitor MEg39 is to be installed on DIN rail TC35, while due to reasons of safety
against electric shock and increased resistance against external machanical impacts, re-
quires covering of cover with terminals by cover panel. DIN rail should be preferentially
in horizontal position, labels on device panel are readable from left to right.
On DIN rail can be installed also power supply MEg101.3a or MEg101.3b and
GPRS communication unit type MEg202.3 if needed. Units are interconnected
using HBUS connector.
Power supply connecting
MEg39 monitor can be supplied either directly by AC voltage or by DC voltage con-
nected to power supply terminals 16 and 18 or by DC 12 V from the UPS MEg101.3 via
the HBUS. Connected to terminals 16 and 18 can be AC voltage within the range from
90 V to 230 V or DC voltage from 100 V to 300 V, independent on polarity.
1. Terminals 16 and 18 of the monitor MEg39 are connected via the two-pole LV fuse
disconnector with fuses 2 A / 500 V to the terminals L and N of the network and their
connection is made with cables certied for installation in a LV cabinet.
2. After a temporary state with a duration of ca 1 s, when the processor is checking the
function of all circuits, it is necessary to check the LED RUN status according to
apreviously programmed measuring mode, see in Tab. 1.
Connecting of measured voltages
Measured voltage must always be led to the reference voltage input U1.
e monitor MEg39 can be used for single-phase measurements, too.

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3. For indirect measurements at the MV and HV level, the measuring voltage inputs are
connected according to the wiring diagrams in Fig. 4 to Fig. 6 to the output terminals
of voltage instrument transformers.
For direct measurements at the LV level, the measuring voltage inputs are connected
to measured voltages at phases L1, L2 and L3 via the three-pole fuse disconnector
with fuses 2 A / 500 V, see in Fig. 7.
When measuring phase voltage of another, non power-connected branch of the LV
network by means of the measuring input U4, it is necessary to insert a one-pole
fuse disconnector with a fuse between the U4 input of the MEg39 monitor and the
measured voltage, see in Fig. 8.
4. When the fuse disconnector is switched „ON“, check the function of the LEDs U1,
U2, U3 and U4, which signalize the status of measured voltage at the corresponding
inputs.
Connecting measured currents
Connecting current circuits must be performed either with the power switched o or
with short-circuited secondary winding of the current instrument transformer.
All current inputs of the monitor MEg39 have the same value of rated current of either
1 A or 5 A, depending on an order.
e type and rated value of primary current of the current instrument transformer is
set by the user according to voltage level and required measured current at the place of
installation.
5. Currents indirectly measured by measuring instrument transformers are connected
via short-circuited current double terminals to the current inputs I1, I2, I3 and I4,
as the case may be, of the monitor MEg39 according to Fig. 4 to Fig. 8. e secon-
dary winding of the current transformer inserted in the L1 phase is connected to
the I1 input, e secondary winding of the current transformer inserted in the L2
phase is connected to the I2 input, e secondary winding of the current transformer
inserted in the L3 phase is connected to the I3 input. Similar procedure is used for
connecting the current input I4, as necessary.