Lumel N20Z TYPE User manual

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USER’S MANUAL
DIGITAL
PANEL METER
N20Z TYPE

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Contents
1. APPLICATION and METER DESIGN........................................... 5
2. METER SET ...................................................................... 5
3. BASIC REQUIREMENTS, OPERATIONAL SAFETY .......................... 6
4. INSTALLATION .................................................................. 7
5. SERVICE.......................................................................... 9
6. ERROR CODES ................................................................. 19
7. TECHNICAL DATA .............................................................. 19
8. ORDER CODES ................................................................. 22
9. MAINTENANCE and GUARANTEE ............................................ 26

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2. METER SET
The set is composed of:
- N20Z meter ......................................... 1 pc
- User’s manual ..................................... 1 pc
- Guarantee card................................... 1 pc
- Clamps to fix in the panel ................... 4 pcs
1. APPLICATION and METER DESIGN
The N20Z meter is a digital programmable panel instrument destined
for measurements of a.c. voltages, a.c. currents, or frequency.
The readout display is a LED display which enables the exposition of
results in red, green or orange colour.
The LPCon program is destined for the configuration of the N20Z meter.
The meter must be connected with the PC computer through a PD14
converter.
Parameters which can be reprogrammed are as follows:
- display colour, individually in three intervals,
- thresholds of displayed overflows,
- display precision of the result (decimal point),
- highlight of the unit,
- kind of the measured signal a.c. or a.c. + d.c. (True RMS),
- averaging time of the measurement,
- recounting of indications (individual characteristic),
- two alarms of OC type operating in six working modes.
The switching of the output alarm on is signaled by the highlight of the
triangular alarm index, at the left side of the display for the suitable
alarm digit
The highlight colour is always different from the colour of the displayed
(measured) value. The protection level from the frontal side is IP 65.
Meter overall dimensions: 96 48 64 mm (including terminals).

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3. BASIC REQUIREMENTS,
OPERATIONAL SAFETY
In the safety service scope, the meter meets the requirements
of the EN 61010-1 standard.
Observations concerning the operational safety:
· All operations concerning transport, installation, and commissioning
as well as maintenance, must be carried out by qualified, skilled
personnel, and national regulations for the prevention of accidents
must be observed.
· Before switching the meter on, one must check the correctness
of connections to the network.
· Do not connect the meter to the network through an
autotransformer.
· Before removing the meter housing, one must switch the supply
off and disconnect measuring circuits.
· The removal of the meter housing during the guarantee contract
period may cause its cancellation.
· The meter fulfills requirements related to electromagnetic
compatibility in the industrial environment
· When connecting the supply, one must remember that a switch or a
circuit-breaker should be installed in the building. This switch should
be located near the device, easy accessible by the operator, and
suitably marked as an element switching the meter off.
· Non-authorized removal of the housing, inappropriate use,
incorrect installation or operation, creates the risk of injury to
personnel or meter damage.
For more detailed information, please study the User’s Manual.
- Seal ..................................................... 1 pc
- Set of labels with units ........................ 1 pc
When unpacking the meter, please check whether the type and
execution code on the data plate correspond to the order.

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Fig. 1 Meter fixing.
Fig. 2 Overall meter dimensions
4. INSTALLATION
The meter has separable strips with screw terminals which enable the
connection of external wires of 2.5 mm2cross-section. In execution for
current measurement, the plug enables a permanent fixing to the so-
cket by means of screws.
One must prepare a hole of 92 +0.6 x 45 +0.6 mm in the panel which the
thickness should not exceed 6 mm.
The meter must be introduced from the panel front with disconnected
supply voltage. Before the insertion into the panel, one must check the
correct placement of the seal.
After the insertion into the hole, fix the meter by means of clamps (fig. 1).

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4.1. Connection diagrams
Fig. 3 Electrical connections of the N20Z meter for voltage
and frequency measurements
Fig. 4 Electrical connections of the N20Z meter for a.c. current
measurements

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5. SERVICE
5.1. Display description
Fig. 5 frontal panel
5.2. Messages after the supply connection
After connecting the supply, the meter displays the N20ZL meter name
– where Lis the letter marking the execution: U– voltage measurement,
I– current measurement, F– frequency measurement, S– custom-made
execution. Next, the program version is displayed in the shape r x.xx
– where x.xx is the number of the actual program version or the number
of the custom-made execution.
Till the time to obtain the required number of correct measurements
(acc. to the table 1), the actual value from the measurement 1 is dis-
played, signaled by the highlighted index of the actual value.
In case of an error occurrence or an overflow of the range value on the
display, a message described in the section 6, will be displayed.
Overflows of the measuring range are additionally signaled by the actual
value signal index.
Alarm
indexes
Highlighted
unit
Measured
value
Index displaying the
current value

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5.3. Meter configuration by means of the
LPCon program
The LPCon program is destined to configure the N20Z meter. One must
connect the meter to the PC computer through the PD14 programmer and
after choosing the menu Options-> Connection configuration, configure
the connection (we choose for the N20Z meter, the address 1, baud rate
9600 kb/s, RTU 8N2 mode, timeout 1000 ms and the suitable COM port
under which the PD14 programmer controller has been installed).
CAUTION! One must carry out the programming of meter parame-
ters when measuring circuits are switched off!
Fig.6. Configuration of the connection with the N20Z meter

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After the connection configuration, one must choose Device Meters
N20Z from the menu and next click the icon Readout in order to read
out all parameters. Parameters can be also read out individually in each
group by clicking the Apply push-button.
5.3.1 Setting of displaying parameters
After choosing the group: - Display, following elements are possible to
be configured:
a) display colours of the measured value. The displayed range is divi-
ded into three zones separated by KpL and KpH threshold values
(suitably the lower threshold KpL and the upper threshold KpH of
display colour change – fig. 7). The colour of displayed numbers for
each zone is selected from three accessible colours: green, oran-
ge and red. KpL and KpH values are set by the user and concern
the displayed value (i.e. taking also into consideration the individual
characteristic). The manufacturer value KpL is equal 100% of the
rated value, however KpH is equal 110% of the rated value, e.g. for
a meter of 400 V execution they are respectively: for KpL – 400 V and
for KpH – 440 V.
Caution!
After setting the individual characteristic, KpL and KpH values
are not automatically updated.
b) decimal point – measurement precision. We have 5 possible display
configurations at choice.
When choosing, one must follow the measurement precision, e.g.:
for the 400 V range – the measurement error is 2 V, so the choice
of precision with two places after the decimal point does not give
more precise measurements. When manufacturing, for executions
with voltage measurement, the precision 0000.0 is set; for execu-
tions with current measurement - 00.000
c) unit highlight. The unit highlight can be enabled or disabled. When
manufacturing, it is enabled.

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Fig. 7. View of the window of display parameter configuration
5.3.2. Setting of measurement parameters
After choosing the group: - measurement parameters, following ele-
ments are possible for the configuration:
a) kind of input: a.c. measurement, a.c. + d.c. measurement (True
RMS), the a.c. measurement is set by the manufacturer.
b) averaging time: till the time to obtain the required number of correct
measurements (according to the table 1), the actual value from 1
measurement is displayed. After measuring a definite number of
measurements, the arithmetic mean of measured measurements is
displayed.

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Table 1
0.5 s 1 every 0.5 s
1 s 2 every 0.5 s
3 s 6 every 0.5 s
5 s 10 every 0.5 s
10 s 20 every 0.5 s
15 s 30 every 0.5 s
30 s 60 every 0.5 s
1 min 100 every 0.6 s
2 min 100 every 1.21 s
5 min 100 every 3 s
7 min 100 every 4.2 s
12 min 100 every 6 s
15 min 100 every 9.1 s
Averaging
time
Number of averaging
measurements
Updating of displayed values
(duration of 1 measurements)
Successive measurements are added under the principle of “walking
window”, i.e. the earliest measurement is rejected and at its place,
is set the measured lately. The measurement of a value beyond the
measuring range causes the display of overflow and the start to count
correct measurements from the beginning.
The time is set on 1 s by the manufacturer.
c) thresholds of displayed overflows: one can narrow limits beyond
which overflows will be displayed, taking into consideration the indi-
vidual characteristic.
When the measured value is beyond 0...120% of the rated value (e.g.
for the 400 V execution, it is the range 0...480 V), the overflow is
displayed.
In manufacturing conditions, the range –19999... 99999 is set.

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d) switching the individual characteristic on. In manufacturing con-
ditions the characteristic is disabled. An example of configuration is
given below for e.g. operation of the N20Z meter when choosing the
kilovolt unit (kV) – the result is divided by 1000.
After pressing the Apply push button, parameters aand bof the
straight line equation are written on the meter.
Fig. 8 View of the window of measurement parameter configuration.
5.3.3. Setting of alarm parameters
After choosing the group: - alarm configuration, following elements
are possible to be configured:
a) alarm 1,
b) alarm 2,

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a) n-on
b) n-off
c) on
d) off
Fig. 9. Alarm types: a) n-on, b) n-off, c) on, d) off.
Remaining types of alarms: h-on – always enabled; h-off – always
disabled.

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Fig. 10. View of the alarm configuration window
5.3.4. Measured values
After choosing the group: - measured values, following information are
displayed:
- measured value of current or voltage, frequency;
- kind of input – execution;
- number of the person responsible for the calibration;
- serial number of the meter.
Both alarms are working independently and each of them has 6 working
modes: nor (in two variants), n-on, n-off, on, off, h-on and h-off, which
are presented on the fig. 9. Alarm thresholds Aoff and Aon are set in
values of the measured quantity taking into consideration the individual
characteristic.
In manufacturing conditions both alarms are set on the n-on mode.
The exemplary configuration of alarms 1 and 2 is presented on the
fig. 10.

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Fig. 11. View of the window of the measured value group
5.4. Manufacturer parameters
Parameter description Range/value Manufacturer value
Display colour of the
measured upper value red, green, orange red (U,I,f)
Display colour of the
measured middle value red, green, orange orange (U,I), green (f)
Display colour of the
measured lower value red, green, orange green (U,I), orange (f)
Upper threshold - KpH -19999... 99999 110% of rated value
Un, In, or 51 Hz
Lower threshold - KpL -19999... 99999 100% of rated value
Un, In, or 49 Hz
Decimal point 00000, 0000.0, 000.00,
00.000, 0.00000,
0000.0 for U,f or
00.000 for I
Highlight of the measured
unit disabled, enabled enabled
Table 2

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Input type AC, AC+DC AC
Averaging time
0.5 s, 1 s, 3 s, 5 s, 10 s,
15 s, 30 s,
1 min, 2 min, 5 min, 7
min, 12 min, 15 min
1 s
Upper overflow of the
measurement -19999... 99999 99999
Lower overflow of the
measurement -19999... 99999 -19999
Individual characteristic disabled, enabled, disabled
Parameter aof the indivi-
dual characteristic -19999... 99999 1
Parameter bof the indivi-
dual characteristic -19999... 99999 0
Action mode of the alarm
output 1
n-on, n-off, on, off, h-on,
h-off n-on (U,I), off (f)
Upper value of the alarm
1 switching - Aon -19999... 99999 110% of rated value Un, In, or 51 Hz
Lower value of the alarm 1
switching - Aoff -19999... 99999 100% of rated value
Un, In, or 49 Hz
Delay of the alarm 1
switching time 0...120 0 second
Action mode of the alarm
output 2
n-on, n-off, on, off, h-on,
h-off n-on (U,I), off (f)
Upper value of the alarm 2
switching - Aon -19999... 99999 110% of rated value Un, In, or 51 Hz
Lower value of the alarm 2
switching - Aoff -19999... 99999 100% of rated value Un, In, or 49 Hz
(continuation) Table 2

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7. TECHNICAL DATA
Measuring range
INPUTS:
Measuring range of voltage Un:
1...100...120 V
2.5... 250...300 V input resistance > 2 M:
4... 400...480 V
Measuring range of current In:
0.01... 1...1,2 A input resistance 50 m:10%
0.05... 5...6 A input resistance 10 m:10%
Frequency measusurement: 20... 500 Hz
(in voltage range 24... 480 V) input resistance > 2 M:
6. ERROR CODES
After connecting the meter to the network, messages about errors may
appears. Causes of errors are presented below:
Overflow of the upper value of the programmed
indication range.
Overflow of the lower value of the programmed
indication range.
ErrCA
ErrEE
Loss of meter calibration values – In such a case, one
must contact an authorized service workshop.
Inappropriate values in meter configuration data. One
must set up meter parameters again by means of the
LPCon program

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Preheating time 30 min.
Intrinsic error
(at manufacturer settings):
- voltage and current (0.5% of the range ±1 digit) in
the frequency interval 20... 500 Hz
- frequency (0.02% of the range ±1 digit)
Additional errors in rated operating conditions:
- from ambient temperature
changes (50% of the intrinsic error/10K)
Averaging time:
- voltage, current (programmable) min 0.5s (1s by default)
- frequency (not programmable) 1s
Alarm outputs outputs of O/C type (30 V, 20 mA),
Passive outputs acc. to EN 62053-31
Rated operating conditions:
- supply voltage 85...253 V a.c. (45...65 Hz) or d.c.
20...40 V a.c. (45...65 Hz) or d.c.
- ambient temperature - 10...23...55C
- storage temperature - 25... + 85C
- relative air humidity < 95% (condensation inadmissible)
- working position any
Sustained overload capacity 120% Un, 120% In
Short duration overload
capacity (3 s):
- voltage input 2 Un (< 1000 V)
- current input 10 In
Readout field 5 three-colour LED displays:
- digit height: 14 mm,
- colours: green, orange, red,
- indication range: -19999...99999