HT HT2055 User manual

Copyright HT ITALIA 2020 Release EN 2.03 - 11/11/2020
ENGLISH
User manual

HT2055
EN - 1
TABLE OF CONTENTS
1PRECAUTIONS AND SAFETY MEASURES.............................................................................. 2
1.1Preliminary instructions ........................................................................................................................ 2
1.2During use ............................................................................................................................................ 3
1.3After use ............................................................................................................................................... 3
1.4Definition of measurement (overvoltage) category .............................................................................. 3
2GENERAL DESCRIPTION .......................................................................................................... 4
2.1Instrument features ............................................................................................................................. 4
3PREPARATION FOR USE .......................................................................................................... 5
3.1Initial inspections .................................................................................................................................. 5
3.2Instrument power supply ...................................................................................................................... 5
3.3Storage................................................................................................................................................. 5
4DESCRIPTION OF PARTS.......................................................................................................... 6
4.1HT2055S station unit description ......................................................................................................... 6
4.1.1Modify of supply voltage for HT2055S unit........................................................................................ 6
4.2Description of test leads ....................................................................................................................... 7
4.2.1Front view.......................................................................................................................................... 7
4.2.2Top view ............................................................................................................................................ 7
4.2.3Backside view.................................................................................................................................... 8
5INITIAL OPERATIONS WITH HT2055M UNIT............................................................................ 9
5.1Settings................................................................................................................................................. 9
5.1.1Language selection ........................................................................................................................... 9
5.1.2Help screen ....................................................................................................................................... 9
5.1.3Synchronization............................................................................................................................... 10
5.1.4Default settings................................................................................................................................ 11
5.1.5Time/Date settings .......................................................................................................................... 11
5.2Messages at display........................................................................................................................... 11
6INITIAL OPERATIONS WITH HT2055S UNIT .......................................................................... 12
6.1Settings............................................................................................................................................... 12
6.1.1Default settings................................................................................................................................ 12
6.1.2Setting output power ....................................................................................................................... 13
6.1.3Setting alarm condition.................................................................................................................... 13
6.2Adjust contrast of display ................................................................................................................... 14
6.3Help screens ...................................................................................................................................... 14
6.4Messages at display........................................................................................................................... 14
7HOW TO PERFORM THE MEASUREMENTS.......................................................................... 15
7.1Theory of Step/Contact voltage measurements................................................................................. 15
7.2Step/Contact voltage measurement................................................................................................... 16
7.3Earth resistance measurement .......................................................................................................... 21
7.4Ground resistivity measurement ........................................................................................................ 23
8OPERATION WITH MEMORY................................................................................................... 25
8.1Saving results..................................................................................................................................... 26
8.2Recall result at display ....................................................................................................................... 26
8.3Delete saved results........................................................................................................................... 27
9CONNECTION OF THE INSTRUMENT TO PC ........................................................................ 28
9.1Installation of software and initial configurations (Win XP) ................................................................ 28
10MAINTENANCE......................................................................................................................... 30
10.1Replacement and charging batteries ................................................................................................. 30
10.2Replacement fuses of HT2055S unit ................................................................................................. 30
10.3Cleaning the instrument ..................................................................................................................... 30
10.4End of life............................................................................................................................................ 30
11TECHNICAL SPECIFICATIONS ............................................................................................... 31
11.1General characteristics....................................................................................................................... 32
11.2Environment ....................................................................................................................................... 33
11.3Standard accessories......................................................................................................................... 33
11.4Optional accessories .......................................................................................................................... 33
12SERVICE ................................................................................................................................... 34
12.1Warranty conditions............................................................................................................................ 34
12.2Service................................................................................................................................................ 34

HT2055
EN - 2
1 PRECAUTIONS AND SAFETY MEASURES
The instrument has been designed in compliance with standards IEC/EN61557-1 and
IEC/EN61010-1 regarding electronic measuring instruments.
CAUTION
For the operator’s safety and to prevent damaging the instrument, follow the
procedures described in this manual and carefully read all notes preceded by
the symbol .
Before and during measurements, carefully observe the following instructions:
Do not perform any measurement in humid environments, in the presence of gas or
explosive or inflammable material or in dusty areas
Even when no measurements are being performed, avoid any contact with the circuit
under test, with exposed metal parts, with unused measuring leads or circuits, etc.
Do not perform any measurement when anomalies are found in the instrument, such as
deformations, breaks, substance leaks, no display view, etc.
During instrument operation, the ventilation holes on casing of HT2055S unit should
always stay open to ensure enough air-flow for cooling
Disconnect all test leads, switch off the instrument and remove the mains cord before
changing the fuse on the HT2055S unit
Pay special attention when measuring voltages above 25V in special environments
(building yards, swimming pools, etc.) and 50V in ordinary environments, as there is
danger of electric shocks.
In this manual and on the instrument, the following symbols are used:
WARNING: Observe the instructions reported in the manual. An improper use
could damage the instrument and lead to dangerous situations for the operator.
AC voltage or current.
Instrument with double insulation.
1.1 PRELIMINARY INSTRUCTIONS
This instrument (HT2055M) has been designed for use in an environment with pollution
level 2
It may also be used to test industrial electrical systems up to CAT II 300V and CAT IV
50V to earth (HT2055S) and CAT IV 50V (HT2055M)
Follow the usual safety rules to protect the operator from dangerous currents and
protect the instrument against improper use
Never use the instrument standing on the floor, it must be placed on flat horizontal
surfaces
Only the accessories supplied with the instrument guarantee safety standards. They
must be in good conditions and replaced, if necessary, with identical models
Do not measure systems exceeding the current and voltage limit values specified
Do not perform measurements under environmental conditions out of the limit values
indicated in this manual
Before connecting the probes to the circuit under test, check that the correct function is
selected

HT2055
EN - 3
1.2 DURING USE
Carefully read the following recommendations and instructions:
CAUTION
Failure to observe the warnings and/or instructions may damage the
instrument and/or its components or generate a danger for the operator
Before selecting a new function, disconnect the measuring probes from the circuit
When the instrument is connected to the circuit under test, never touch any unused
lead
The auxiliary current probe can be subject to a higher voltage. Avoid the contact with
this probe during measurement
Avoid measuring resistance with external voltages. Even if the instrument is protected,
as an excess voltage may cause instrument malfunctions
1.3 AFTER USE
When measurements are completed, turn off the instrument by pressing the ON/OFF key.
1.4 DEFINITION OF MEASUREMENT (OVERVOLTAGE) CATEGORY
Standard "IEC/EN61010-1: Safety requirements for electrical equipment for measurement,
control and laboratory use, Part 1: General requirements", defines what is intended for
measurement category, commonly known as overvoltage category. In § 6.7.4: Measuring
circuits, it reads:
Circuits are divided into the following measurement categories:
Measurement category IV is for measurements performed at the source of a low-
voltage installation.
Examples are electric counters and measurements on primary devices protecting
against overcurrents and on ripple adjusting units.
Measurement category III is for measurements performed on installations inside
buildings.
Examples are measurements performed on distribution boards, circuit breakers, wiring
harnesses, including cables, bars, junction boxes, switches, sockets of fixed
installations and appliances designed for industrial use and other equipment, e.g.
stationary motors connected to fixed systems.
Measurement category II is for measurements performed on circuits directly
connected to the low-voltage installation.
Examples are measurements performed on household appliances, portable tools and
similar equipment.
Measurement category I is for measurements performed on circuits not directly
connected to the MAINS.
Examples are measurements performed on circuits not derived from the MAINS and on
circuits derived from the MAINS provided with a special (internal) protection. In this
latter case, the stress caused by the transients is variable; therefore, (OMISSIS) it is
necessary that the user knows the appliance’s resistance to transients.

HT2055
EN - 4
2 GENERAL DESCRIPTION
The instrument HT2055 you purchased grants accurate and reliable measurements as
well as the utmost safety provided it is used in compliance with the indications given in this
manual. Thanks to a new concept development it ensures double insulation and,
consequently, compliance with the requirements of overvoltage category IV.
The instrument is composed of the following two units:
HT2055S Station unit which can generate the test current in order to perform the
step/contact voltage and the earth/resistivity measurements
HT2055M Meter unit in order to perform the step/contact voltage measurements with
test current generated by the station unit.
2.1 INSTRUMENT FEATURES
Step/contact voltage measurement with test current of max 55A
Earth resistance measurement with 4 wire method
Ground resistivity measurement with Wenner method
Use of metal plates for step/contact voltage measurement
Initial synchronizing for autonomous use of the meter unit
DSP internal filtering for compensation of disturbance effect on the measurement
Internal memory for saving test
USB interface for data transfer to PC
Use of rechargeable batteries on meter unit
A dot matrix LCD offers easy-to-read results and all associated parameters. The operation
is straightforward and clear to enable the user to operate the instrument without the need
for special training (except reading and understanding this user manual).
Test results can be stored on the instrument. The new professional PC SW enables
straightforward transfer of test results and other parameters in both directions between the
test instrument and PC

HT2055
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3 PREPARATION FOR USE
3.1 INITIAL INSPECTIONS
Before shipment, the instrument’s electronics and mechanics were inspected. All possible
precautions were taken to permit delivery of instrument free of damage. However, we
recommend generally inspecting the instrument in order to detect any damage suffered
during transport. Should you detect any anomalies, immediately contact the forwarding
agent or the dealer. Moreover, we recommend checking that the package contains all
parts listed in § 11.3. Should you find any discrepancy, please contact the dealer. Should it
be necessary to return the instrument, please follow the instructions reported in § 12.
3.2 INSTRUMENT POWER SUPPLY
The station unit HT2055S is power-supplied by 230V ± 10%, 50/60Hz mains while the
meter unit HT2055M is power-supplied through 6x1.2V IEC AA internal rechargeable
batteries which are recharged from the mains by means of a battery charger supplied as
standard accessory. The use of 6x1.5V type AA LR6 alkaline batteries is also possible for
this unit. The symbol “ “ indicates that the batteries are low and must be recharged.
To recharge or replace the batteries, follow the instructions given in § 10.1
CAUTION
Use NiMh rechargeable batteries IEC LR6 all of the same type for the
HT2055M unit
Do not charge alkaline battery cells

A
t the first use of HT2055M unit connect the instrument to the mains power
supply for at least 14 hours to fully charge batteries. When you charge the
batteries for the first time, it normally takes about 4 charge and discharge
cycles for the batteries to regain full capacity
3.3 STORAGE
In order to guarantee accurate measurements and protect the instrument from possible
failures, after a long storage period under extreme environmental conditions, wait for the
instrument to return to a normal condition (see the environmental specifications listed in §
11.2).

HT2055
EN - 6
4 DESCRIPTION OF PARTS
4.1 HT2055S STATION UNIT DESCRIPTION
Fig. 1: HT2055S unit description
CAPTION:
1 Protection fuse on mains (see § 11.1)
2 Switch for supply voltage selection (110/230V)
3 ON/OFF key to switch the instrument ON or OFF
4 Input connector for mains cord
5 RS-232 galvanic port for connection to HT2055M unit
6 C1/H terminal for connection of auxiliary earth probe
7 P1/S for connection of auxiliary voltage probe
8 P2/ES for connection of auxiliary current probe
9 C2/E for connection of auxiliary earth probe
10 HELP key
11 – 12 and keys for function selection and parameter settings
13 LCD display with backlit
14 Key for adjust contrast of display
15 MEM key for access to internal memory (see § 8)
16 ESC key to return at previous screen
17 , , , arrow keys and TEST key to activation measurements
4.1.1 Modify of supply voltage for HT2055S unit
1. Open the fuses compartment (see Fig. 1 – Part 1) with a screwdriver
2. Extract the red switch (see Fig. 1 – Part 2) from the fuses compartment
3. Rotate the switch in way to correctly read the “115V” or “230V” indication
correspondent to the desired supply voltage
4. Restore the switch in the fuses compartment and close it

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EN - 7
4.2 DESCRIPTION OF TEST LEADS
4.2.1 Front view
Fig. 2: HT2055M unit front view description
CAPTION:
1 ESC key to return at previous screen
2 MEM key for access to internal memory (see § 8)
3 , , , arrow keys and TEST key to activation measurements
4 Backlight key
5 LCD display
6 ON/OFF key to switch the instrument ON or OFF
7 - 8 and keys for function selection and parameter settings
4.2.2 Top view
Fig. 3: HT2055M unit top view description
CAPTION:
1
Test connector.
CAUTION: maximal allowed voltage between test terminals and ground is
50V. Maximal allowed voltage between test terminals is 100V
2 Power supply socket
3 PS/2 connector (for RS232 communication)
4 Protection cover
5 USB connection

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4.2.3 Backside view
Fig. 4: HT2055M unit backside view description
CAPTION:
1 Battery compartment cover
2 Safety information label
3 Fixing screws for battery compartment cover
Fig. 5: HT2055M battery compartment description
CAPTION:
4 Serial number label
5 Battery cells (6x1.2V NiMH type AA)
6 Battery compartment

HT2055
EN - 9
5 INITIAL OPERATIONS WITH HT2055M UNIT
Press the or function keys to display the below screens relative to the Step
Voltage, Contact Voltage and Settings (see Fig. 6)
Fig. 6: Screens of general menu
5.1 SETTINGS
The below operations are possible within Settings menu:
Language selection
Help screens on connections
Syncronizing with the station unit HT2055S
Restore of default conditions
Recall at display of saved results (see § 8.2) and clear memory (see § 8.3)
Setting of system time/date
5.1.1 Language selection
Fig. 7: Screen of language selection
1. Press or keys to enter Settings menu
2. Select the item “Select Language” with the or keys and press TEST key
3. Select the desired language with the or keys and confirm with TEST key
4. Press ESC key to exit and go back to the previous screen
5.1.2 Help screen
Fig. 8: Help screen
1. Press or keys to enter Settings menu
2. Select the item “Help” with the or keys and press TEST key
3. Select the desired help screen with the or keys
4. Press ESC key to exit and go back to the previous screen

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EN - 10
5.1.3 Synchronization
Selecting this option will allow to upload different data from the station unit to the meter
unit. The possible options are:
Synchronization of the actual time/date and the generated current
Uploading of test current results for Step / Contact voltage calculation
Uploading of earth resistance and ground resistivity results
Fig. 9: Synchronization screen
1. Press or keys to enter Settings menu
2. Select the item “Synchronize” with the or keys and press TEST key
3. Connect both units by using the PS/2-RS-232 supplied cable
4. Select one of the below options with the or keys and confirm with TEST key
TIME, CURRENT Station’s time and date will be uploaded to the meter. Value
of generator current will be uploaded to the meter
STEP/CONTACT VOLT Values of logged generator currents IGEN will be uploaded to
the Meter for calculation of Step voltage or Contact voltage
EARTH RESULT Stored earth resistance or ground resistivity results in the
station will be uploaded to the meter
5. Press ESC key to exit and go back to the previous screen
CAUTION
The main purpose of the Time/ Current synchronization is to enable a
correction of the step and contact voltage results after the test. During the
test the step and contact voltage results are calculated based on the IGEN
set on the meter. After the test the obtained results can be updated with
the real generator currents IGEN measured at the same time with the
station. The stored USTEP and UCONTACT values are then corrected
according to the following formula:
SET
generatedactuallyGEN
STEPoldSTEPnew I
I
UU )_( 
SET
generatedactuallyGEN
CONToldCONTnew I
I
UU )_( 
The synchronization is active for 24 h
If date / time are changed on the meter or station the synchronization of
time and date will be lost. The current logger must be cleared before it can
proceed with measurements. Before clearing it you can download its
content to the meter

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EN - 11
5.1.4 Default settings
This section permits to restore the default value (factory) of measurement parameters and
limits set on the instrument
Fig. 10: Initial settings screen
1. Press or keys to enter Settings menu
2. Select the item “Initial Settings” with the or keys and press TEST key
3. Select the “NO” or “YES” options with the or keys and confirm with TEST
4. Press ESC key to exit and go back to the previous screen
The default values are the following:
Language English
Contact and Step voltage
IGEN = 10A
IFLT = 1kA
RINP = 1MΩ
ULIM = 50V
5.1.5 Time/Date settings
Fig. 11: Time/Date settings screen
1. Press or keys to enter Settings menu
2. Select the item “Set Date/Time” with the or keys and press TEST key
3. Use the ,,and keys to set the date/time and confirm with TEST
4. Press ESC key to exit and go back to the previous screen
5.2 MESSAGES AT DISPLAY
The below messages (icons) can be displayed on the meter unit:
The meter and the station are not synchronized
Measurement is running
Results can be stored
Measurement result is within pre-set limits (PASSED)
Measurement result is out of pre-set limits (FAILED)

HT2055
EN - 12
6 INITIAL OPERATIONS WITH HT2055S UNIT
Press the or function keys to display the below screens relative to the
earth/resistivity measurements and Settings (see Fig. 12)
Fig. 12: Screens of general menu
6.1 SETTINGS
The below operations are possible within Settings menu:
Language selection (see § 5.1.1)
Restore of default conditions
Setting power of current generator
Setting of alarm conditions when switching off test current
Recall at display of saved results (see § 8.2) and clear memory (see § 8.3)
Time/date setting (see § 5.1.5)
6.1.1 Default settings
This section permits to restore the default value (factory) of measurement parameters and
limits set on the instrument
Fig. 13: Initial settings screen
1. Press or keys to enter Settings menu
2. Select the item “Initial Settings” with the or keys and press TEST key
3. Select the “NO” or “YES” options with the or keys and confirm with TEST
4. Press ESC key to exit and go back to the previous screen
The default values are the following:
Contrast 50%
Language English
Alarm Disabled
Power of generator 100%
Distance “a” 2.0m

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EN - 13
6.1.2 Setting output power
This section permits to set the output power of current generator by selecting the
percentages: 10%, 25%, 50%, 75% and 100%
Fig. 14: Output power generator setting screen
1. Press or keys to enter Settings menu
2. Select the item “Power Range” with the or keys and press TEST key
3. Select the desired percentage with the or keys and confirm with TEST
4. Press ESC key to exit and go back to the previous screen
CAUTION
When the current generator is started the output power is automatically set to
the available maximum value. If the conditions change during the
measurement the generator may switch off. Possible causes for switching off
are:
The output can become overloaded by high external earth currents. In this
case it is recommended to decrease the output power down to 75% or 50%
and restart the generator
The current stopped flowing abruptly. If stop was caused by disconnection
of the leads it is not necessary to lower down the power. The generator can
be restarted.
6.1.3 Setting alarm condition
This section permits to set an acoustic alarm condition when stopping current generation
due to noise effect or unexpected opening of circuit under test
Fig. 15: Alarm condition setting screen
1. Press or keys to enter Settings menu
2. Select the item “Alarm” with the or keys and press TEST key
3. Select the options “ENABLED” or “DISABLED” with the or keys and confirm with
TEST
4. Press ESC key to exit and go back to the previous screen
CAUTION
An active alarm helps to avoid wrong interpretation of the Step and Contact
voltage results. The readings will be close to 0 V if no test current is flowing

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EN - 14
6.2 ADJUST CONTRAST OF DISPLAY
1. Press the key. The following screen is shown:
2. Use the or keys to reduce or increase the contrast percentage of display
3. Press the TEST key to confirm the operation or the ESC key to exit from this function
6.3 HELP SCREENS
1. Pressing screen to display the help screen correspondent to the selected function
2. Use the or keys to select the other help screens
3. Press ESC key to exit and go back to the previous screen
6.4 MESSAGES AT DISPLAY
The below messages/screens can be displayed by the station meter:
Voltage between test terminals C1/H and C2/E is higher than
allowed (>10 V). Disconnect the test leads and check why an
external voltage was detected
During current generation output was overloaded or test current
abruptly fell down. Overload can be caused by high spurious earth
current. In this case it is recommended to decrease the output power
(see § 6.1.2)
Output current is too low (< 0.2A). A too low current can be caused
because of bad connection or high probe resistance
Date / time was changed in the station and consequently the
synchronization between station and meter gets lost. The current
logger must be cleared. Before clearing it its contents can be
downloaded to the meter
Output power is not set to maximum
Measurement is running
Results can be stored
High electrical noise was detected during measurement. Results may be
impaired
High resistance of current (c) and/ or voltage (p) probes. Results may be
impaired

HT2055
EN - 15
7 HOW TO PERFORM THE MEASUREMENTS
7.1 THEORY OF STEP/CONTACT VOLTAGE MEASUREMENTS
An earth electrode / grid depleted into ground has a certain resistance, depending on its
size, surface (oxides on the metal surface) and the soil resistivity around the electrode.
The earth resistance is not concentrated in one point but is distributed around the
electrode. Correct connection of exposed conductive parts assures that the voltage on
them stays below dangerous level in case of a fault.
If a fault happens a fault current will flow through the earth electrode. A typical voltage
distribution occurs around the electrode (the “voltage funnel”). The largest part of the
voltage drop is concentrated around the earth electrode. The Fig. 16 shows how fault, step
and contact voltages occur as a result of fault currents flowing through the earth electrode
/ grid in the ground.
Fault currents close to power distribution objects (substations, distribution towers, plants)
can be very high, up to 200 kA. This can result in dangerous step and contact voltages. If
there are underground metal connections (intended or unknown) the voltage funnel can
get atypical forms and high voltages can occur far from the point of failure. Therefore the
voltage distribution in case of a fault around these objects must be carefully analyzed.
Fig. 16: Dangerous voltages on a faulty earth system
The guidelines define limit values of step/contact voltages depending on the time of fault
elimination by the protection devices (typically declared by the Mains Energy provider). If
the value of fault voltage is over this limit it is necessary to verify that the values of
step/contact voltages in some potentially dangerous points of the plants (e.g: access
areas, close to metal structures normally de-energized, gates, safety nets, etc) fall within
standard values.

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EN - 16
7.2 STEP/CONTACT VOLTAGE MEASUREMENT
The measurements of step/contact voltage are performed by a voltmeter with an internal
resistance of 1ksimulating the body resistance and with two weight probes of 25 kg
each simulating feet. Alternatively it is possible to use two metal plates instead of
weight probes on the ground where the operator stands.
CAUTION
During the measurement a test current is injected into the earth through an
auxiliary probe. The resistance of the auxiliary probe should be as low as
possible in order to inject a high test current. The resistance can be decreased
by using more probes in parallel or using an auxiliary earth system as
auxiliary probe. A higher injected current improves the immunity against
spurious earth currents.
As the test current is usually only a small fraction of the highest fault current the measured
voltages must be up scaled according to the following equation:
Gen
Fault
MeasuredCS I
I
UU 
,
US,C………..calculated step or contact voltage in case of fault current
UMeasured ….measured voltage during the test
IFault………..maximal earth current in case of a fault
IGen………..injected test current
Installation of station unit
1 Place the station unit close to the earth system under test (distance max. 10m).
Connect the unit at the input terminal C1/H by using the supplied cable
2 Fit the auxiliary metal probe (1m length) on the ground at a distance of at least 5 times
the maximum diagonal of the earth system under test (see Fig. 17). Connect the input
terminal C2/E to the probe by using the 50m long cable (if enough) or use another
customized cable for longer distances. The nature of the measurement method permits
the use of different cables without any resistance compensation. Use also several
probes connected in parallel among them if it is necessary to reduce the contact
resistance on that point.

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EN - 17
Fig. 17: Circuit scheme for step voltage measurement
Fig. 18: Circuit scheme for contact voltage measurement
Generation of test current
3 Switch on the station unit HT2055S
4 Use or keys and select the “CURRENT GEN.” screen (see Fig. 19)
Fig. 19: Test current generation screen

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EN - 18
5 Press TEST key to activate the operation. The value of generated current is displayed.
Check this value.
CAUTION
The output power is set automatically to its available maximum value (see
§ 6.1.2)
Completely unwind measuring cable to avoid affecting test current value
(coil impedance)
Usually the resistance of auxiliary probe can affect the generated test
current. The injected current can be increased by placing more probes in
parallel.
Synchronization between the units before the test (recommended)
Before starting with the step/contact voltage measurements it is recommended to
synchronize the meter and the station units. The synchronization sets the same date and
time in both units. Therefore the measured voltages can be correctly scaled after the
measurements. If the current is generated during the synchronization its value is also sent
to the meter unit (see § 5.1.3)
6 Connect both meter and station units through the PS/2-RS-232 cable supplied as
accessory (see Fig. 20)
Fig. 20: RS-232 connection between units
7 Select the option “Synchronize Time, Current” on the meter unit (see § 5.1.3) and
confirm with TEST key. The messages “Connecting...” and “Synchronizing…”are
displayed.
CAUTION
The measurements can be carried out without synchronization. In this case
the measuring current must be set / changed manually. If the injected current
is changing during the test the IGEN parameter must be adjusted manually. The
measurement results cannot be corrected after the measurement.

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Perform step/contact voltage measurements
8 Use or keys and select the CONTACT VOLT or STEP VOLT measurements
on the meter unit
Fig. 21: Screens for step/contact voltage measurements
9 Use ,,and keys and perform the settings of the following test parameters:
Igen Test current (manual setting considering the range 0.20A ÷ 50A) or
automatically fitted by the station unit during the synchronization
Iflt Maximum fault current of earth system (range 10A ÷ 200kA)
Rinp Input resistance of the meter unit (1M, 1k)
Ulim Limit value for step/contact voltage measurements (range 1V ÷ 10kV)
Iflt Fault current value given by the Mains Energy provider
Rinp Input resistance fixed to 1kfor step/contact voltage measurements
Ulim Voltage limit given by Guidelines according to the time of fault elimination by the
protection devices
10 Place and connect the test metal plates to each other where the operator stands, close
to the points where step voltage measurement (see Fig. 17) or contact voltage (see
Fig. 18) is required respecting the necessary distances
11 Connect the metal plates to the meter unit by using the cables supplied
12 Press TEST key on the meter unit and perform the step voltage of the contact voltage
measurements. The following screens are displayed by the meter:
Fig. 22: Screens for results of step/contact voltage measurements
Where:
U calculated step/contact voltage
Um measured step/contact voltage
13 Press MEM key to save the result inside memory (see § 8.1)