Meatest M525 User manual

M-142 Multifunction Calibrator
Operation Manual

M-142 Multifunction Calibrator MEATEST, s.r.o.
2User Manual v54
Content
Basic Information ..................................................................................................................... 5
Preparation for operation......................................................................................................... 6
Inspecting package contents, selecting the installation location....................................................6
Power-on.............................................................................................................................................6
Warm-up time....................................................................................................................................6
Replacement of fuse...........................................................................................................................7
Storing.................................................................................................................................................7
Safety precautions..............................................................................................................................7
Description of controls.............................................................................................................. 8
Front panel .........................................................................................................................................8
Rear panel.........................................................................................................................................14
Control of the calibrator ......................................................................................................... 15
Selection of function.........................................................................................................................15
Setting the value of output signal ...................................................................................................15
Setting relative deviation.................................................................................................................17
Change of value by factor of ten.....................................................................................................18
Connection / disconnection of output terminals............................................................................ 18
Setting the frequency.......................................................................................................................19
Generation of calibrated voltage ....................................................................................................20
Generation of calibrated current....................................................................................................22
Generation of non-harmonic shapes ..............................................................................................23
Simulation of resistance and capacitance ......................................................................................24
Generation of electric power and energy.......................................................................................26
Generation of frequency..................................................................................................................31
Simulation of temperature sensors.................................................................................................34
Multimeter............................................................................................................................... 38
Basic menu........................................................................................................................................38
Function selection.............................................................................................................................39
Setting the measurement range ...................................................................................................... 39
Units of measurement......................................................................................................................39
Use of calculation formula...............................................................................................................40
Setting function parameters............................................................................................................41
Start of measurement ......................................................................................................................42
Zero function....................................................................................................................................42
Simultaneous functions.................................................................................................................... 44
Setup menu.............................................................................................................................. 45
Calibration mode..................................................................................................................... 49

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Error messages ........................................................................................................................67
Functional description of the calibrator.................................................................................69
Calibrator’s maintenance........................................................................................................75
Verification test........................................................................................................................77
System control..........................................................................................................................86
IEEE-488 bus properties..................................................................................................................86
RS232 bus properties........................................................................................................................86
Command syntax..............................................................................................................................87
Standard Status Data Structures ..................................................................................................101
Examples of use.....................................................................................................................104
Calibration of measuring instruments..........................................................................................104
Multimeters .................................................................................................................................................104
Powermeters................................................................................................................................................106
Counters and oscilloscopes..........................................................................................................................108
Thermometers..............................................................................................................................................108
Measurement using the calibrator................................................................................................109
Voltage, current and frequency ...................................................................................................................109
Measurement of resistance or temperature using resistance temperature sensors .......................................109
Measurement of temperature using thermocouples.....................................................................................110
Testing of control unit, transducers and evaluation units ..........................................................110
Option 40/60 cable adapter application.......................................................................................................110
Option 70 application ..................................................................................................................................110
Option 80 application ..................................................................................................................................111
Option 90 application ..................................................................................................................................111
Examples of tests.........................................................................................................................................112
Specification...........................................................................................................................113
Accessories.............................................................................................................................120
Operation Manual Supplement.............................................................................................122
Change 1..........................................................................................................................................122
Change 2..........................................................................................................................................122
Change 3..........................................................................................................................................122
Change 4..........................................................................................................................................122
Change 5..........................................................................................................................................122
.............................................................................................123

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List of tables
Tab. 1 Functions 8
Tab. 2 Reference values 8
Tab. 3 Auxiliary connector description 10
Tab. 4 Display buttons description 12
Tab. 5 Cable adapters description 43
Tab.6 DC VOLTAGE calibration points 53
Tab.7 AC VOLTAGE calibration points 53
Tab.8 DC CURRENT calibration points 54
Tab.9 AC CURRENT calibration points 54
Tab.10 DC POWER calibration points 55
Tab.11 AC POWER calibration points 55
Tab.12 R calibration points 56
Tab.13 C calibration points 57
Tab.14 F calibration points 57
Tab.15 Multimeter calibration points 57
Tab. 16 Error messages 67
Tab. 17 RS232 connector description 84
Tab. 18 Recommended way of signal terminal grounding 105
Tab. 19 Application of cable adapters 107
Tab.20 Overview of cable adapters 109
Table I Verification test VDC 20V 80
Table II Verification test VDC 80
Table III Verification test VAC 20V 80
Table IV Verification test VAC 81
Table V Verification test ADC 200mA 81
Table VI Verification test ADC 81
Table VII Verification test AAC 82
Table VIII Verification test AACDC High current 82
Table IX Verification test ACDC Power 82
Table X Verification test R 82
Table XI Verification test C 82
Table XII Verification test F 83
Table XIII Verification test Multimeter 83

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Basic Information
M-142 Multifunction Calibrator is a multifunction calibrator, to be used primarily as a standard
for calibration laboratories. It can be used for calibration of any measuring instrument which measures voltage,
current, resistance, capacitance and frequency. It generates fixed non-harmonic signals to allow calibration
of measuring instruments using signals with non-zero harmonic distortion. Frequency, amplitude and duty cycle
of output signal can be adjusted. M-142 Multifunction Calibrator is also suitable for basic calibration
of oscilloscopes.
The calibrator includes a function which simulates resistance and thermocouple temperature sensors
and a built-in multimeter, which can be used simultaneously. Transducers of various types, regulators and
sensing units can be therefore checked without the need for additional measuring instruments.
Basic features of the calibrator include generation of calibrated DC and AC voltage in the range of 0 V
to 1000 V, DC and AC current in the range of 0 A to 30 A (50 A to 1000 A when using a 50-turn coil). The
best accuracy of the calibrator is 0.0015 % for DC voltage. Maximum frequency range is 20 Hz to 100 kHz. The
calibrator can generate periodic non-harmonic signal with defined duty cycle. This facilitates especially the
checks of multimeters and their accuracy when measuring non-harmonic DC signals.
The calibrator can also simulate a resistance or capacitance. Resistance range is 0 to 1000 M;
capacitance range is 1 nF to 100 F, the accuracy suits the calibration of common multimeters. Basic accuracy
of resistance ranges is 0.015 %. Basic accuracy of capacitance ranges is 0.5 %.
Frequency ranges of the calibrator can generate a squarewave signal with definable and calibrated duty
cycle and amplitude in the 1 mV to 200 V range and 0 to 10 kHz frequency range. Moreover, squarewave signal
with very steep rising edge can be generated up to 20 MHz. Frequency ranges can be used to calibrate the
corresponding frequency ranges of multimeters, as well as to calibrate the input sensitivity and time bases of
oscilloscopes.
Powermeter mode can be used to calibrate DC and AC single phase powermeters and energy meters.
Voltage range is up to 240 V and current range is up to 20 A, power factor range is -1 to +1 and the resolution is
1 % in the 40 Hz to 400 Hz frequency range. The voltage output can supply loads up to 30 mA, which allows the
calibration of mechanical powermeters.
Simulation of temperature sensors is yet another feature which can be used to calibrate thermometers
and heat sensing units. The calibrator allows the simulation of all common Pt and Ni resistance sensors and R, S,
B, J, T, E, K, N type thermocouples. Compensation of cold junction of thermocouple is achieved by entering
the respective temperature using the calibrator’s keyboard. The accuracy of simulated temperature sensors
depends on the value and type of sensor and ranges from 0.04 oC to 0.5 oC for resistance sensors and from
0.4 oC to 4.3 oC for thermocouples.
Internal multimeter with 20 mA, 20 mV, 200 mV and 10 V basic ranges and 0.01 % accuracy can be
used to measure normalized signals coming from transducers, external thermocouples or resistance sensors or to
measure pressure and force using strain gauge sensors.
The calibrator includes many other features which facilitate easy use. For example relative deviation from set
value of the output, currently displayed uncertainty of the output signal, calibration and testing procedures etc.
The concept of calibrator control and indication of its status is based on flat luminiscent display, which provides
all necessary information. The calibrator is controlled by opening menus on the display and selection from
menus. Frequently used functions are assigned direct-control keys. The calibrator comes with standard GPIB bus
and RS-232 serial line, which allow the calibrator to be controlled from a PC.
The calibrator can easily fit within calibration systems featuring WinQbase/CALIBER software
support.
ATTENTION !
The calibrator generates life-threatening high voltage.
The calibrator can only be used in line with this manual.

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Preparation for operation
Inspecting package contents, selecting the installation location
Basic package includes the following items:
•Multifunction calibrator
•Power cord
•Spare fuse T4L250/T, T8L250/T
•Operation manual.
•Test report
•Test cable 1000V/20 A 2 pcs
•Cable adapter Option 40
•Cable adapter Option 60
•Cable adapter Option 70
•Cable adapter Option 80
•RS 232 cable
The calibrator should be powered by 230/115 V –50/60 Hz mains. It is a laboratory instrument whose
parameters are guaranteed at 232 oC. Before powering on the instruments, place it on a level surface. Do not
cover the vents at the bottom side and the fan opening at the rear panel. Leave the calibrator to stabilize to
ambient temperature and humidity at minimum 4 hours after unpacking.
If you need to reship the Calibrator, use the original container. If it is not available, you can order a new
container from manufacturer by identifying the Calibrator’s model and serial number.
Power-on
•Before connecting the calibrator to the mains, check the position of the mains voltage selector located at the
rear panel.
•Plug one end of the power cord into the connector located at the rear panel and connect the other end of the
power cord into a wall outlet.
•Switch on the mains switch located at the rear panel. Flat display is lit.
•The calibrator performs internal hardware checks for 5 seconds.
•After the tests conclude, the calibrator resets to its reference state, i.e. the following parameters are set:
Function DC voltage
Range 20 V
Set value 10 V
Output terminals OFF
GPIB address of the calibrator is factory-preset to 2. This value is valid until the user changes it.
Note. The calibrator resets to its reference status in case of power switching off and reconnection.
Warm-up time
The calibrator works after it is switched on and the initial checks complete. Specified parameters are only
guaranteed after the instrument warms up for 60 minutes. During this period, the instrument cannot be calibrated.
The display shows “cannot access the calibration” message if calibration is attempted during this period.

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Replacement of fuse
The calibrator includes a fuse located in the mains connector at the rear panel. Replace the fuse as follows:
•Switch off the calibrator
•Remove the end of power cord from the mains connector at the rear panel.
•Insert the blade of a flat screwdriver into the opening cut in the mains voltage selector and pull out the fuse
holder.
•Remove the fuse and replace it with new fuse of the same rating.
Storing
The calibrator can be stored in original packing under storing conditions specified in chapter Specification.
Safety precautions
The instrument has been designed in Safety Class I according to EN 61010-1. The design reflects the
requirements of A2 amendment of the standard.
Safety is ensured by the design and by the use of specific component types.
The manufacturer is not liable for the damage caused by modification of the construction or replacement of parts
with non-original ones.
Safety symbols used on the equipment
Warning, reference to the documentation
Warning - risk of electric shock
Danger - high voltage

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Description of controls
Front panel
The front panel of the calibrator includes a flat luminiscent display, control buttons and output terminals. The
following picture shows the control part of the front panel.
1Display buttons
There are five buttons below the display, whose meaning changes depending on the contents of the display.
These buttons usually call-up the MENU, allow range change, step, logging of values etc.
2Cursor buttons
Using these buttons, the cursor can be controlled within allowed limits on the display. The keyboard includes
two buttons (<, >) which allow the cursor to be set to the required position at the display. The cursor can be
moved to the left or right. These buttons are usually used to step through the options and to move from one
option to another or between the menu levels. Numeric values can be set in some control modes as well. In these
cases, the buttons marked (, ) allow the user to increase or decrease the number at the cursor button.
The central button is used to confirm the selection (ENTER), or to SELECT from the menu.
3Potentiometer
The potentiometer integrates several functions. By turning the knob to the left or right, the user can:
•step through the options
•enter numeric values
The function of the potentiometer can usually be performed by the cursor buttons. The central button is used to
confirm the selection (ENTER).
3
5
1
2
4
6
7

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4Numeric keyboard
The keyboard allows the entry of numeric values on the display. The central button is used to confirm the
selection (ENTER). CANCEL button can be used to cancel the entry.
5Function buttons
Function buttons can be used to call-up the functions of the calibrator directly. The following buttons are
provided:
function
button
DC voltage
U / DC
AC voltage
U / AC
DC current
I / DC
AC current
I / AC
resistance / capacitance
R –C
power / energy
P –E
frequency
F
internal multimeter
METER
simulation of temperature sensors
T
Tab. I One touch buttons
After the function mode is changed, the parameters of the respective function are restored. If the respective
function was never used, the calibrator resets to its reference values. Reference values for individual functions
are listed below.
function
value
parameters
DC voltage
10V
- -
AC voltage
10 V
f = 1000 Hz
DC current
100 mA
- -
AC current
100 mA
f = 1000 Hz
resistance
100 k
capacitance
1 F
power
100 W
f = 100 Hz *1
energy
frequency
1000 Hz
U = 1 Vsym
multimeter
10 V
DC voltage
simulation of temperature sensors
100 oC
Pt 100/1.385, ITS90
cold junction temperature of TC sensors
23 oC
R
Tab. 2 Reference values
*1 U = 100 V, I = 1 A, PF(power factor) = 1 LA, active power is displayed in Watts

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6Output / input terminals buttons
OUTPUT button is used to connect the output signal of the calibrator to the output terminals. The connection is
confirmed by red LED and a symbol at the display.
METER button can be used to connect the input terminals to the internal multimeter. The connection is
confirmed by green LED.
7Output / input terminals
Output signal of the calibrator is connected to the output terminals. Current ranges are connected to +I / -I
terminals, frequency output is connected to FREQ terminal. All other functions (voltage, resistance,
capacitance) are connected to Hi / Lo terminals.
GND terminal is connected to the chassis of the calibrator. It is connected to the ground terminal of the mains
plug. Using the SETUP MENU of the calibrator, the output terminals of the calibrator can be grounded as well.
Grounding is done internally by connecting Lo and GND terminals using a relay. This circuit design is suitable
for most calibrations, when the object (multimeter) being calibrated is floating.
AUXILIARY connector creates input of internal multimeter. It includes a limited range of output signals of the
calibrator as well. The layout of individual pins and their meanings are listed in the following table.
Auxiliary connector can be used with one of cable adapters Opt. 40, 60, 70, 80, 90 Opt. 140-01. Calibrator can
recognize which type of adapter is connected and displays the information on front panel display.

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pin
label
signal
Limitation
1
0V5MER
common terminal of multimetr power supply source
2
GND
ground (protection earth)
3
SIMLI
RC simulator output, current terminal Li
Umax.= 10Vpp, Imax.=40mA
4
SIMLU
RC simulator output, voltage terminal Lu
Umax.= 10Vpp, Imax.=40mA
5
GND
ground (protection earth)
6
L
common terminal of multimeter input
7
-U
low output terminal for DC voltage range
8
-I
low output terminal for DC current range
9
NG2
sort function output, contact 2 of sort relay
Umax.=50Vpp, Imax.=100 mA
10
PTLI
resistance temperature sensor input terminal Li
Umax.= 10Vpp. R<2 k
11
PTLU
resistance temperature sensor input terminal Lu
input terminal L on ranges 20, 200, 2000 mV
Umax.= 10Vpp. R<2 k
12
TEST1
identification terminal of actually used adapter
13
TEST3
identification terminal of actually used adapter
14
0V5MER
common terminal of multimeter power supply source
15
NC
not used
16
SIMHI
RC simulator output, current terminal Hi
Umax.= 10Vpp, Imax.=40mA
17
SIMHU
RC simulator output, voltage terminal Hu
Umax.= 10Vpp, Imax.=40mA
18
NC
not used
19
INP
multimeter input terminal for voltage/current ranges
Umax.=25 Vpp, Imax.=25 mA
20
+U
high output terminal for DC voltage range
Umax.=20 Vss
21
+I
high output terminal for DC current range
Imax.=25 mA
22
NG1
sort function output, contact 1 of relay
Umax.=50Vpp, Imax.=100 mA
23
PTHI
resistance temperature sensor input terminal Hi
Umax.= 10Vpp. R<2 k
24
PTHU
resistance temperature sensor input terminal Hu
input terminal H on ranges 20, 200, 2000 mV
Umax.= 10Vpp. R<2 k
25
TEST2
identification terminal of actually used adapter
TEST1
Tab. 3 Auxiliary connector description
Functional inputs and outputs present at the connector can be best utilized using supplied cable adapters.
LCD display shows all information provided by the calibrator, e.g. set parameters of the signal, error messages,
setup information. The display is divided to several information sections.

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8Display
1a 1b 1c 1d 1e 2a 3 2b 1g 1f
The display is divided to three horizontal sections:
1. OUTPUT section
This section displays the set-up values of generated signals and the data related to the calibrator status. The
section includes the following types of data:
a) Information line
•designation of display section: OUTPUT
•error messages. The messages appear when an attempt is made to set up an invalid state of the
calibrator, if analogue circuits of the calibrator are overloaded or if a communication error occurs
when the calibrator is controlled using GPIB bus.
•real date and time, if its display is set-up in the setup menu.
b) Auxiliary data
This line displays the total value of output signal if a non-zero relative deviation is set.
c) Main data
This line displays the main data of the output signal and the unit of measurement (using double size
signs). The line also includes two symbols (▼▲) to define the actual position of the cursor during
adjustment of the value. <, > buttons can be used to move the cursor and , buttons to change the
value. (The value can be also changed using the potentiometer).
d) Monitoring line
This line displays the numbers entered using the numeric keyboard when the main data are set using the
numeric keyboard. The information allows the entered information to be checked.
e) Minor data
There are two lines displaying the minor data of the output signal, especially:
•set relative deviation from main set value in %
•frequency (for DC voltage, current, power, energy functions)
•set value of current, voltage or power factor (phase) for power, energy functions

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•value of R0 resistance and the type of resistance temperature sensor
•cold junction temperature of TC sensors and the selected type of TC sensor
•value of amplitude and shape type for frequency function
f) Information section
The information section located in the right part of the display displays additional information related to
the selected function:
•symbol of connected or disconnected output terminals.
At the same time, a LED located above the OUTPUT button is lit.
•information about remote/local control of the calibrator. If the calibrator is controlled remotely,
REM is displayed. If the calibrator is controlled locally using the keyboard, LOCAL is displayed.
•information about the use of 50-turn coil (COIL x50) at the current output of the calibrator, if this
feature is turned on using the SETUP menu.
•information about the type of connected cable adapter, if used
•information about the grounding method of output terminals: GND I, GND U as set up using the
setup menu.
g) Information about the uncertainty of the output signal
This section displays the maximum error of the main value of the output signal. The value is calculated
using the main specification listed in the User’s Manual and it is displayed in %.
2. INPUT section
This section displays the values measured by the multimeter. The section includes following data:
a) Main value of measured signal
This line displays the measured value and the unit of measurement. If the input signals exceed the
permitted range, OVERFLOW is displayed.
b) Designation of selected function of the multimeter
Symbolic display of selected function of the multimeter: V DC, mA DC, mV DC, R 4W, Freq, T TC, T
RTD, ACAL.
3. Display buttons section
This line displays the symbolic descriptions which define the meaning of four related display buttons. The
respective meanings are as follows:
symbol
button function
note
x 10
increase set value 10 x
: 10
decrease set value 10 x
Shape
selection of signal shape
only for U, I, F functions
+/-
reversed polarity of output voltage and current
only for DC U, DC I functions
EXIT
move up one level
only for F, P-E functions
Calib.
enter the calibration menu
SETUP
enter the setup menu
TC type
selection of thermocouple sensor type
only for T function
RTD type
selection of resistance temperature sensor type
only for T function
f
enter the frequency of the signal
only for U, I function
MODE
select the unit of measurement
only for AC P-E function
Tab. 4 Display buttons description

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Rear panel
The rear panel of the calibrator includes ventilation holes, power cord socket with fuse, mains voltage selector,
mains switch, IEEE 488 connectors for connection to GPIB bus and type plate with serial number.
1 air inlet - forced ventilation
2 air outlet - forced ventilation
3 GPIB, RS-232 connectors
4 power cord socket with fuse, mains voltage selector, mains switch
5 type plate
5 1 2
4 3

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Control of the calibrator
Selection of function
After the power is switched on and the initial checks complete, the calibrator resets to its reference status, i.e. DC
voltage output with set value of 10 V and output terminals disconnected. Internal multimeter is switched off. The
status of the calibrator can be changed using the buttons located at the front panel in one of the following ways:
1. Change of function by pressing one of direct function buttons
After pressing one of the U, I, DC-AC, R-C, P-E, F, T, METER buttons, the calibrator switches to the desired
function mode and resets to the reference or to the most recently used parameter setting.
2. Connection /disconnection of output terminals
After pressing the OUTPUT button, the output terminals of the calibrator are connected/disconnected.
3. Connection /disconnection of multimeter
After pressing the INPUT button, the multimeter starts measuring the value present at the input terminals,
depending on the function mode of the multimeter. The measurement is only possible when any of Opt. 140-xx
adapters is connected to the AUXILIARY connector.
4. Entry to the setup menu
After pressing the SETUP button, options of the SETUP MENU appear on the display and the display buttons
allow the entry to the calibration mode (CALIB). Previous function is restored by pressing of EXIT display
button.
Setting the value of output signal
All function modes allow several methods of setting the main value of the output signal:
Entry of the value using numeric keyboard
•use the numeric keyboard to select the desired value. After the first digit is entered, symbols of unit
of measurements are displayed above the display buttons. The monitor line displays the symbols
[ _ _ _ _ _ _ _ _ ].
•the same entry can be started by pressing the central cursor button
•after the entry is complete (the value is displayed on the monitor line), press the display button
below the desired unit of measurement (V, mV or V in the example below)
•the value is copied to the main display and the monitor line disappears.

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Entry of the value using cursor buttons
•press , , or button. The display now includes cursor marks which point to the active digit.
•and buttons can be used to change the active digit. , buttons can be used to change the
position of the cursor marks
•to get to the default screen, press EXIT button or keep pressing the center cursor button until there
is no [ _ _ _ _ _ _ _ ] under any value. All values can be set using the buttons or the potentiometer.
Entry of the value using the potentiometer
•press the potentiometer knob. The display now includes cursor marks which point to the active
digit
•turn the knob to change the active digit
•press the potentiometer knob to change to the mode which allows to change the value of the active
digit. ← and → symbols are displayed above the active digit. Active digit can be changed by
turning the knob.
•turn the knob to change back to the mode which allows to change the position of the active digit.
•to get to the default screen, keep pressing the center cursor button until there is no [ _ _ _ _ _ _ _ ]
under any value, or press EXIT button. All values can be set using the buttons or the potentiometer.
Reverse polarity
In DC voltage and DC current modes, the polarity of the output value can be reversed by pressing +/- display
button. „ - “ symbol appears in front of the main data value.

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Setting relative deviation
All function modes of the calibrator except frequency mode allow a relative deviation of output value from the
main data to be set using a separate display. Relative deviation is displayed in the “minor data” section of the
display and is designated with „ %= 00.0000 % “ symbol. The relative deviation can be entered using one of
the methods described above, e.g. using the numeric keyboard, cursor keys or the potentiometer.
Setting relative deviation using numeric keyboard
•keep pressing the center cursor button until [ _ _ _ _ _ _ _ ] symbols appear under the relative
deviation value in the “minor data” section of the display
•enter the desired deviation and confirm the value by pressing “ % “ display button or by pressing
ENTER on the numeric keyboard
•the auxiliary line below the main data on the display displays the total value of output signal
including the unit of measurement
•the value of the signal at output terminals is: the value indicated by the main display + ∆ %.
Maximum relative deviation which can be entered is 30.000 %.
The deviation can be positive or negative. If negative deviation is desired, press the display button labeled +/-. If
positive deviation is then desired, press “ +/- “ button again. The polarity of the relative deviation can be
reversed using the cursor buttons or the potentiometer as well.
Setting relative deviation using cursor keys
•keep pressing the center cursor button until [ _ _ _ _ _ _ _ ] symbols appear under the relative
deviation value
•press , , or button. The display now includes cursor marks which point to the active digit
•and buttons can be used to change the active digit. , buttons can be used to change the
position of the cursor marks
•to get to the default screen, keep pressing the center cursor button until there is no [ _ _ _ _ _ _ _ ]
under any value, or press EXIT button. All values can be set using the buttons or the
potentiometer..

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Setting relative deviation using potentiometer
•keep pressing the center cursor button until [ _ _ _ _ _ _ _ ] symbols appear under the relative
deviation value in the “minor data” section of the display
•press the potentiometer knob. The display now includes cursor marks which point to the active
digit. Turn the knob to change the value of the active digit
•press the potentiometer knob to change to the mode which allows to change the position of the
active digit. ← and → symbols are displayed above the active digit. The position of the active digit
can be changed by turning the knob.
•turn the knob to change back to the mode which allows to change the value of the active digit
•to get to the default screen, keep pressing the center cursor button until there is no [ _ _ _ _ _ _ _ ]
under any value, or press EXIT button. All values can be set using the buttons or the potentiometer.
If a non-zero relative deviation is set, the main data can be changed as well. The value of the output signal is
always recalculated. If a zero relative deviation is set, the “minor data” section is not displayed.
Change of value by factor of ten
All functions of the calibrator allow the increase of the output value by 10 or reduction of the output value by 10.
Such operation is equivalent to the change of internal range only in U, I, P-E modes. If the change results in
overflow or underflow of calibrator’s range, an error message appears:
Value too large ! if the resulting value is too large
Value too small ! if the resulting value is too small
Range change
•Press the display button labeled “ x10 “ if you want to increase the range, “ :10 “ to decrease the
range.
•The main value shown on the display is increased 10x (reduced 10x)
P-E function changes the current, not voltage, when the range is changed.
R-C function changes the set value 10x. The procedure, however, cannot be used to step the internal
resistance/capacitance ranges, which are not decimal.
T function also has other than decimal ranges and the change of set value 10x therefore does not correspond to
internal range change. Internal range change in this case depends on the temperature sensitivity of the
resistance/capacitance.
Connection / disconnection of output terminals
After switching on the output terminals are disconnected in all modes. Press the OUTPUT button to connect the
output signal to the terminals. Red LED above the OUTPUT button is lit and the information field on the
display shows the following symbol .
Press the OUTPUT button again to disconnect the output terminals. Red LED goes off and the information field

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on the display shows the following symbol .
During mode change, output terminals are always disconnected. Output terminals are disconnected also when
changing between voltage and current ranges or when changing between AC and DC ranges is performed.
If voltage over 100 V is set in the voltage mode, special algorithm must be followed to connect the output
terminals. The algorithm is described in the „Generation of calibrated voltage“ chapter of this Manual.
Setting the frequency
Frequency can only be selected in AC voltage (ACU) mode, AC current (ACI) mode , power (P-E) mode and
frequency (f) mode. In each mode the frequency has a slightly different meaning and the frequency is therefore
set in a different manner.
AC voltage (ACU), AC current (ACI)
Set value of frequency is included in the “minor data” section of the display in ACU, ACI, P-E modes.
Frequency change
•First select the AC voltage or AC current mode by pressing U (I), AC buttons or selecting the P-E
mode using the display. Frequency value „f = xxx.xx Hz“ appears in the “minor data” section of
the display. “ f “ symbol is displayed above one of the display buttons.
•After “ f “ display button is pressed, [ _ _ _ _ _ _ _ ] symbols appear below the frequency value.
Numeric keyboard can be used to enter the desired value. Press “ Hz “ or “ kHz “ to confirm the
value. The value can be set using the buttons or the potentiometer.
If too large or too small value is entered, the calibrator displays the maximum (minimum) value which is allowed
for the selected function.
Frequency (F)
Set value of frequency is the main data on the display and the main parameter of the signal. Main data can be set
by direct entry using the numeric keyboard, potentiometer or by changing the digit at the current cursor position.
The setting procedure is described in the “Setting the value of output signal”.

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If frequency larger or smaller than the calibrator’s range is entered, the calibrator displays an error message:
„Value is too large (small)“.
Generation of calibrated voltage
The multifunction calibrator provides calibrated DC and AC voltage. Output terminals for voltage ranges are
labeled “ Hi “ and “ Lo “ at the front panel. Depending on the setting of the calibrator, voltage up to 1000 Vef
can be present at the terminals .
DC voltage range is 0 to 1000 V.
AC voltage range is 100 V to 1000 V.
Control in the voltage mode
•Press “U” button on the calibrator and then select AC or DC mode by pressing “DC-AC” button. The
display shows the following data:
* main data of set voltage
* relative deviation
* uncertainty of output voltage
* frequency (when AC voltage is generated)
* total value of output voltage when non-zero relative deviation is set
•Set the desired value of voltage, including polarity when necessary, frequency and relative deviation. The
signal is yet not connected to the output terminals. The information section of the display shows the symbol
which informs about the disconnection of output terminals.
•Press OUTPUT button.
•Red LED is lit above the OUTPUT terminals to signal the connection of the signal to the output terminals;
the information section of the display shows the symbol .
•Calibrated voltage corresponding to set parameters is present at the output terminals.