NARDA EHP-50-G User manual

NARDA
Safety
Test
Solutions
S.r.l. Socio Unico
Sales & Support:
Via Leonardo da Vinci, 21/23
20090 Segrate (MI) - ITALY
Tel.: [phone]
Fax: [phone]
Manufacturing Plant:
Via Benessea, 29/B
17035 Cisano sul Neva (SV)
Tel.: [phone]
Fax: [phone]
http://www.narda-sts.it
SERIAL NUMBER OF THE INSTRUMENT
You can find the Serial Number on the bottom cover of the instrument.
The Serial Number is in the form: 000XY00000.
The first three digits and the two letters are the Serial Number prefix, the last five
digits are the Serial Number suffix. The prefix is the same for identical instruments, it
changes only when a configuration change is made to the instrument.
The suffix is different for each instrument
Document EHP50GEN-81007-1.71 – Copyright © NARDA 2018
User’s Manual
EHP-50G
ELECTRIC AND MAGNETIC
FIELD PROBE - ANALYZER
From 1 Hz up to 400 kHz

II Note and symbols
NOTE:
® Names and Logo are registered trademarks of Narda Safety Test Solutions GmbH and L3 Communications
Holdings, Inc. – Trade names are trademarks of the owners.
If the instrument is used in any other way than as described in this User’s Manual, it
may become unsafe.
Before using this product, the related documentation must be read with great care and fully understood to familiarize
with all the safety prescriptions.
To ensure the correct use and the maximum safety level, the User shall know all the instructions and
recommendations contained in this document.
This product is a Safety Class III instrument according to IEC classification and has
been designed to meet the requirements of EN61010-1 (Safety Requirements for
Electrical Equipment for Measurement, Control and Laboratory Use).
In accordance with the IEC classification, the power supply of this product meets requirements Safety Class II and
Installation Category II (having double insulation and able to carry out mono-phase power supply operations).
It complies with the requirements of Pollution Class II (usually only non-conductive pollution). However,
occasionally it may become temporarily conductive due to condense on it.
The information contained in this document is subject to change without notice.
EXPLANATION OF ELECTRICAL AND SAFETY SYMBOLS :
You now own a high-quality instrument that will give you many years of reliable service.
Nevertheless, even this product will become obsolete. When that time comes, please remember
that electronic equipment must be disposed of in accordance with local regulations. This product
conforms to the WEEE Directive of the European Union (2002/96/EC) and belongs to Category 9
(Monitoring and Control Instruments). You can return the instrument to us free of charge for
proper environment friendly disposal. You can obtain further information from your local Narda
Sales Partner or by visiting our website at www.narda-sts.it .
Warning, danger of electric shock Earth
Read carefully the Operating Manual and its
instructions, pay attention to the safety
symbols.
Unit Earth Connection
Earth Protection Equipotential
EXPLANATION OF SYMBOLS USED IN THIS DOCUMENT :
The DANGER sign draws attention to a serious risk to a person’s safety,
which, if not avoided, will result in death or serious injury. All the
precautions must be fully understood and applied before proceeding.
The WARNING sign indicates a hazardous situation, which, if not avoided,
could result in death or serious injury. All the precautions must be fully
understood and applied before proceeding.
The CAUTION sign indicates a hazardous situation, which, if not avoided,
could result in minor or moderate injury.
The NOTICE sign draws attention to a potential risk of damage to the
apparatus or loss of data.
The NOTE sign draws attention to important information.

Contents III
Contents
Page
Safety requirements and instructions…..........…….....…………………
EC Declaration of Conformity ..........................………………................
VII
VIII
1 General information Page
1.1 Documentation......................................................….……..................
1.2 Introduction ……………….....................…………………..…………….
1.3 Configuration and Standard accessories............................................
1.4 Optional accessories ..............................................…………………..
1.5 Main specifications.................................................……….................
1.6 Isotropic E&H field analyzer EHP-50G typical uncertainty
and Anisotropy…………………………………………………………….
1.6.1 Typical uncertainty of EHP-50G………………………………………
1.6.2 Explication Notes……………………………………………………….
1.6.3 Measurements uncertainty of EHP-50G (Weighted Peak mode)…
1.7 Anisotropy………………………………………………………………….
1.8 Overload level…………………………………………………………….
1.9 EHP-50G panel...................................………..………………………..
1-1
1-1
1-3
1-3
1-4
1-5
1-5
1-6
1-7
1-8
1-11
1-12
2 Software interface Page
2.1 Introduction…………….........................................…...………………..
2.2 Preliminary inspection…….............................……...…...…………….
2.3 Work Environment………..........................…………..………………..
2.4 To return for repair…..…..................................……...……………….
2.5 Equipment cleaning………..…….….................……...…..……………
2.6 Power supply and battery recharging………………………................
2.7 EHP-50G connected to a PC……………………………..…………….
2.8 EHP-50G stand alone mode….….………………………..……………
2.9 EHP-50G with 8053B DISPLAY.………………………….……………
2.10 Battery management…………….………………………..…………..
2.11 Avoiding measurement errors……………………………................
2-1
2-1
2-1
2-1
2-1
2-2
2-3
2-3
2-3
2-3
2-4
3 EHP-TS installation Page
3.1 Introduction…………………………………………………..……………
3.2 Hardware requirements…………………………...………..……………
3.3 Installing EHP-TS Software………….………………..…………………
3-1
3-1
3-2

IV Contents
4 EHP50-TS software Page
4.1 EHP50-TS Applications……………………………………..…
4.2 EHP-50F Applications.……….....……………………………..
4.2.1 Main menu………………….…………………………………
4.3 Mode section.…………………………………………………..
4.4 Span section……………...…………………………………….
4.5 Standard…………………………………………………………
4.6 Data section…………………………………………………..…
4.6.1 Waterfall……………………………………………………….
4.6.1.1 Data recording………………………………………………
4.7 Style section.…………………………………………………….
4.8 ICNIRP…………………………………………….………..……
4.9 IEEE………..………………………………………………..…..
4.10 Weighted Peal Function (Time Domain) [Optional]…..…..
4.10.1 Weighted Peak requirements……………………………..
4.10.1.1 Weighted Peak Activation Procedure………………….
4.10.2 EHP-TS Settings..………………………………………….
4.10.3 Weighted Peak Mode………………………………………
4.10.3.1 Dynamic ranges………………………………………….
4.11 Additional functions provided by EHP-200TS……………..
4-1
4-2
4-2
4-4
4-5
4-7
4-9
4-13
4-17
4-18
4-19
4-21
4-23
4-23
4-23
4-24
4-25
4-27
4-29
5 EHP-50G Stand alone mode Page
5.1 Stand alone mode description………….………………….….
5.2 EHP-50G Data Logger…………………………………………
5.2.1 Run EHP-50G Stand Alone mode software……………….
5.2.2 Use EHP-50G Logger………………………………………..
5.2.3 EHP-50G battery charging…………………………………..
5-1
5-2
5-2
5-5
5-5
6 Update Firmware Page
6.1 Update firmware…………..……………………………………
6.2 To run the update software..………………………………….
6.3 To transfer data ………………………………………………..
6.4 Dongle Utility……………………………………………………
6-1
6-1
6-1
6-4
7 Uninstalling software Page
7.1 Uninstalling EHP-TS Software ………………………..………
7-1
8 Uninstalling USB-OC Page
8.1 Uninstalling driver for USB-OC……………..……………..…..
8-1

Contents V
9 Accessories Page
9.1 Introduction………………….…………………………….......
9.1.1 Preliminary inspection……..…...………………………......
9.1.2 Work environment….……………………………………….
9.1.3 Return for repair………………………………………….…
9.1.4 Cleaning…………………………………………………..….
9.1.5 Power supply and battery chargers…………………….…
9.1.6 Weighted Peak Option……………………………………..
9.2 USB-OC Optical USB Converter…………………………....
9.2.1 Introduction…………………………………………………..
9.2.2 Installation…………………………………………………...
9.3 8053-OC Optical RS232 Converter…………………..…..…
9.3.1 Introduction………………………………………………..…
9.3.2 Installation…………………………………………….……..
9.4 8053-OC-PS Power Supply………………………..…..……
9.4.1 Introduction………………………………………………….
9.4.2 Installation…………………………………………………...
9.5 8053B DISPLAY Unit…………………………………………
9.5.1 Introduction………………………………………………….
9.5.2 Standard Accessories……………………………………...
9.5.3 Optional Accessories.……………………………………...
9.5.4 8053B Main Specifications…..…………………………….
9.5.5 Field Probes…………………………………………………
9.5.6 8053B Front Panel……………………………………….…
9.5.7 8053B Side Panel…………………………………………..
9.5.8 8053B Battery charger….………………………………….
9.5.9 To substitute the mains connector………………………..
9.5.10 To check the internal batteries…………………………..
9.6 TR-02A Tripod…………………………………………….......
9.6.1 Introduction……………………………………………..……
9.7 TT-01 Fiber glass Telescopic support…………….…..……
9.7.1 Introduction……………………………………………..……
9.8 Other accessories……………………………………..………
9-1
9-1
9-1
9-1
9-1
9-2
9-2
9-3
9-3
9-3
9-4
9-4
9-4
9-5
9-5
9-5
9-6
9-7
9-7
9-7
9-8
9-9
9-10
9-10
9-11
9-11
9-11
9-12
9-12
9-14
9-14
9-15

VI Contents
Figures
Figure Page
1-1
1-2
1-3
1-4
1-5
1-6
3-1
4-1
4-2
4-3
4-4
4-5
4-6
4-7
4-8
4-9
4-10
5-1
6-1
6-2
7-1
8-1
9-1
9-2
9-3
9-4
9-5
9-6
9-7
9-8
9-9
Block Diagram of the EHP-50G ………………….
3D mesh measurements of magnetic probe…….
EHP-50G axes……………………………………..
Overload level EHP-50G (B Field, RMS)………..
Overload level EHP-50G (E Field, RMS)………..
EHP-50G panel ........………...............…………..
EHP-TS Installation………………………………..
EHP50 EHP-TS Main Window……………………
Defining frequency band through the PC mouse
Zoom window……………………………………….
Data section…………………………………………
Waterfall - Graph 2D……………………………….
Waterfall Main Window…………………………….
Waterfall - Graph 3D……………………………….
Electric and magnetic fields……………………….
Power density spectrum…………………………..
New wave impedance function…………………..
Shorting loop………………………………………..
EHP-50G Upgrading Utility Main Window……....
EHP-50G Options activation Utility Main Window
Uninstalling EHP-TS……………………………….
Uninstalling USB-OC………………………………
USB-OC Adapter..…………………………………
8053-OC Panels……………………………………
8053-OC-PS Connectors………………………….
8053B………………………………………………..
8053 Logger Interface software…………….……
8053 Front Panel……………………………..……
8053 Side Panel……………………………………
TR-02A Tripod…..……………………….…………
TT-01 Fiber Glass Telescopic Support…………..
1-2
1-8
1-9
1-11
1-11
1-12
3-2
4-3
4-5
4-6
4-9
4-13
4-14
4-15
4-29
4-29
4-30
5-1
6-1
6-4
7-1
8-2
9-3
9-4
9-5
9-6
9-6
9-10
9-10
9-12
9-14
Tables
Table Page
1-1
2-1
9-1
9-2
9-3
9-4
9-5
9-6
9-7
Technical Specifications of the EHP-50G….…....
Autonomy of the battery……………………………
Technical Specifications of the USB-OC………...
Technical Specifications of the 8053-OC…..……
Technical Specifications of the 8053-OC-PS……
Technical Specifications of the 8053 DISPLAY…
EHP-200A Electric and Magnetic Field Probe…..
Technical Specifications of the TR-02A….………
Technical Specifications of the TT-01……………
1-4
2-3
9-3
9-4
9-5
9-8
9-9
9-12
9-14

EC Conformity VII
SAFETY RECOMMENDATIONS AND INSTRUCTIONS
This product has been designed, produced and tested in Italy, and it left the factory in conditions fully
complying with the current safety standards. To maintain it in safe conditions and ensure correct use,
these general instructions must be fully understood and applied before the product is used.
•When the device must be connected permanently, first provide effective grounding;
•If the device must be connected to other equipment or accessories, make sure they are all safely
grounded;
•In case of devices permanently connected to the power supply, and lacking any fuses or other
devices of mains protection, the power line must be equipped with adequate protection
commensurate to the consumption of all the devices connected to it;
•In case of connection of the device to the power mains, make sure before connection that the
voltage selected on the voltage switch and the fuses are adequate for the voltage of the actual
mains;
•Devices in Safety Class I, equipped with connection to the power mains by means of cord and plug,
can only be plugged into a socket equipped with a ground wire;
•Any interruption or loosening of the ground wire or of a connecting power cable, inside or outside the
device, will cause a potential risk for the safety of the personnel;
•Ground connections must not be interrupted intentionally;
•To prevent the possible danger of electrocution, do not remove any covers, panels or guards
installed on the device, and refer only to NARDA Service Centers if maintenance should be
necessary;
•To maintain adequate protection from fire hazards, replace fuses only with others of the same type
and rating;
•Follow the safety regulations and any additional instructions in this manual to prevent accidents and
damages.

VIII Safety Consideration
Dichiarazione di Conformità
EC Declaration of Conformity
In accordo alla Decisione 768/2008/EC, conforme alle direttive EMC 2014/30/UE, Bassa Tensione 2014/35/UE e RoHS
2011/65/UE, ed anche alle norme ISO/IEC 17050-1 e 17050-2.
In accordance with the Decision 768/2008/EC, compliant to the Directives EMC 2014/30/EU, Low Voltage 2014/35/EU and
RoHS 2011/65/EU, also compliant to the ISO/IEC standard 17050-1 and 17050-2
Il costruttore
The manufacturer narda Safety Test Solutions S.r.l. Socio Unico
Indirizzo
Address Via Benessea, 29 / B
I-17035 Cisano sul Neva (SV) - Italy
sulla base delle seguenti norme europee armonizzate, applicate con esito positivo:
based on the following harmonized European Standards, successfully applied:
EMC - Emissioni:
EMC - Emission: EN 61326-1 (2013)
EMC - Immunità:
EMC - Immunity: EN 61326-1 (2013)
Sicurezza:
Safety: EN 61010-1 (2010)
dichiara, sotto la propria responsabilità, che il prodotto:
declares, under its sole responsibility, that the product:
Descrizione
Description
SONDA ANALIZZATORE DI CAMPO ELETTRICO E MAGNETICO
ELECTRIC AND MAGNETIC FIELD PROBE - ANALYZER
Modello
Model EHP-50G
è conforme ai requisiti essenziali delle seguenti Direttive:
conforms with the essential requirements of the following Directives:
Bassa Tensione
Low Voltage 2014/35/EU
Compatibiltà Elettromagnetica
EMC 2014/30/EU
RoHS
RoHS 2011/65/EU
Cisano sul Neva, 20 April 2016 Egon Stocca
General Manager

General Information 1-1
1 - General information
1.1 Documentation
The following documents are included in this Manual:
•A questionnaire to be sent to NARDA together with the apparatus
should service be required.
•A checklist of the Accessories included in the shipment.
This Manual includes description of EHP-50G standard and optional
accessories.
1.2 Introduction
This section provides a general overview of EHP-50G Electric and
Magnetic Field Analyzer.
EHP-50G is a low frequency electric and magnetic isotropic field probe-
analyzer. It provides an advanced technology solution for field analysis in
the 1 Hz to 400 kHz frequency range in an extremely high dinamic range. It
includes X, Y and Z axes simultaneous measurements with a powerful,
built in, spectrum analyzer.
EHP-50G can be used either connected to 8053B portable field meter or
PC. Additionally, stand alone operation mode is provided for up to 24 hours
continuous data collection.
EHP-50G includes a non volatile memory which stores frequency and level
calibration tables and an internal optical repeater which allows connection
to external devices through the optical fibre.
Spectral analysis, obtained through DSP (Digital Signal Processor), is
performed on seven different frequency Span values and displayed on the
PC monitor or 8053B.
Marker function is available to provide accurate field strength and
frequency measurement.
EHP-50G is managed internally with a microprocessor that controls all the
main functions, from the battery charging to the serial communication with
the DSP unit.
Electric or Magnetic field is picked up by three sensors on the X, Y and Z
orthogonal axes. A Digital/Analog conversion follows which transforms the
signal into numeric information processed by a Digital Signal Processing
unit.
Document EHP50GEN-81007-1.71 - © NARDA 2018

1-2 General Information
EHP-50G is housed in a small cubic housing. The bottom side panel
includes an optic fiber connector, extension rod screw, battery charger
connector, ON/OFF button and Status LED.
Fig. 1-1 Block diagram of the EHP-50G Analyzer
The magnetic sensor system is composed by three magnetic loops
positioned orthogonal each other. The electric sensor system is composed
by three orthogonal parallel capacitors installed on opposite side of the
magnetic loops.

General Information 1-3
1.3 Configuration and
Standard Accessories
EHP-50G can be purchased as part of two different sets, for 8053B or
Stand-alone/PC use, which difference consist of the included accessories.
•8053-SC Soft carrying case, holds basic unit and accessories including
8053-Display;
•AC/DC battery charger;
•International AC plug adapter;
•FO-8053/10 Cable, fibre optic 10m
•FO-10USB Cable, fibre optic 10m;
•USB-OC Optical to USB converter;
•Optical bridge connector;
•Plastic rod support, 50cm;
•Mini tripod, bench top;
•EHP-TS Software Media;
•Operating manual EHP-50G;
•Certificate of calibration;
•Return for Repair Form
1.4 Optional Accessories
The following accessories may be ordered as options:
•2013/35 kit (including the EHP-50G itself);
•8053B;
•SB-04 Switching Control Box;
•FO-20USB Cable, fiber optic 20m;
•FO-40USB Cable, fiber optic 40m;
•FO-8053/20 Cable, fiber optic 20m;
•FO-8053/40 Cable, fiber optic 40m;
•FO-8053/80 Cable, fiber optic 80m;
•8053-OC Optical to RS232 converter;
•8053-OC-PS Power Supply;
•TR-02A wooden tripod 1-2m with soft carrying bag;
•TT-01 telescopic mast (120-420 cm) with carrying bag;
•8053-CC Rigid case;
•8053-CA Car Adapter.

1-4 General Information
1.5 EHP-50G Main
specifications
When not differently specified the following specifications are
referred to operating ambient temperature 23°C and relative
humidity 50%.
Table 1-1 Technical specifications of the EHP-50G Electric and Magnetic Field Analyzer
Electric Field Magnetic Field AUX input (MMCX Zin 1kΩ)
Frequency range 1 Hz ÷ 400 kHz
Measurement range (1) low range
high range
5 mV/m ÷ 1 kV/m
500mV/m ÷ 100 kV/m
(146 dB)
0.3 nT ÷ 100 µT
30 nT ÷ 10 mT
(150 dB)
30 nV ÷ 10 mV
3 uV ÷ 1 V
(150 dB)
Overload (high range) 200 kV/m (≤3 kHz) 20 mT (at 50 Hz) 2V
Dynamic range 106 dB 110 dB 110 dB
Resolution (2) 0.1 mV/m
1 mV/m Stand alone
0.1 nT
1 nT Stand alone
0.1 nV
Displayed average noise level (3)
Isotropic result
Single axis
5 mV/m
3 mV/m
0.3 nT
0.2 nT 30 nV
Flatness (@ 100 V/m, 3 µT, 1mV)
(5 Hz ÷ 40 Hz)
(40 Hz ÷ 300 kHz)
(300 kHz ÷ 400 kHz)
±0.35 dB
±0.35 dB
±0.35 dB
±0.50 dB
±0.35 dB
±0.50 dB
±0.35 dB
±0.35 dB
±0.35 dB
Anisotropicity (typ) 0.54 dB 0.12 dB ---
Linearity (referred to 100 V/m and 3 µT) 0.2 dB (1 V/m ÷ 1 kV/m) 0.2 dB (200 nT ÷ 10 mT) 0.2 dB (10 µV ÷ 1 V)
Internal memory Up to 24 hours regardeless the logging rate
Internal data logger 1 measurement every 30 or 60 seconds
Spectrum analysis method FFT
Time domain analysis method (4) ICNIRP 1998, 2010 and 2013/35/EU weighed peak analysis
Acquisition method Simultaneous three axis acquisition
SPAN 100 Hz, 200 Hz, 500 Hz, 1 kHz, 2 kHz, 10 kHz, 100 kHz, 400 kHz
(500Hz to 400kHz in Stand Alone mode)
Start frequency 1 Hz with SPAN 100 Hz; 1.2 % of the SPAN with wider SPAN
Stop frequency Equal to the SPAN
Immunity to E fields --- < 0.2 uT @ 20 kV/m ---
Immunity to H fields < 10 V/m @ 1 mT --- ---
Calibration (5) internal E2PROM
Typical temperature deviation
@ 55 Hz referred to 23°C
(@ 50% of relative humidity when applicable)
-4x10-3 dB/°C within -20 +55 °C -8x10-3 dB/°C within -20 +23 °C
+13x10-3 dB/°C within +23 +55 °C ---
Typical relative humidity deviation
@ 55 Hz referred to 50%
(@ 23 °C)
+11x10-3 dB/% within 10 50 %
+22x10-3 dB/% within 50 90 %
-7x10-3 dB/% within 10 50 %
+10x10-3 dB/% within 50 90 % ---
Dimensions 92 x 92 x 109 mm
Weight 550 g
Tripod support Threaded insert ¼”
Environmental protection IP42
Internal battery 3.7 V / 5.4 Ah Li-Ion, rechargeable
Operating time >9 hours in standard mode
24 hours in stand alone mode
Recharging time < 6 hours
External supply 10 ÷ 15 VDC, I = approx. 500 mA
Optical fiber connection Serial Optical Interface 38400 Baud - RP02 connector up to 40 m (USB-OC)
Firmware updating through the optical link by USB or RS232
Self test automatic at power on
Operating temperature -20 to +55 °C
Operating relative humidity (6) 0 to 95 %
Charging temperature 0 to +40°C
Storage temperature -30 to +75°C
(1) For each single axis. Ranges to be selected manually
(2) For the lower measurement range
(3) DANL is frequency and SPAN depending. The specified best performance is referred to f ≥50 Hz and SPAN ≤1 kHz
(4) The FPGA operates in the time domain, implementing the hardware filters exactly as if the analog signal were passing through a chain of RC filters, being able to reconfigure poles and
zeroes to adapt to legislations.
(5) Recommended re-calibration interval 24 month
(6) Without condensation
Specification are subject to change without notice

General Information 1-5
1.6 Isotropic E&H field
analyzer EHP-50G
uncertainty
and anisotropy
The uncertainties have been determined according to EA-4/2 [4] and are
expressed as relative values.
They were estimated as expanded uncertainty obtained multiplying the
standard by the coverage factor k=1.96, corresponding to a confidence level
of about 95%.
1.6.1 Measurements
Uncertainty of EHP-50G
(Spectrum mode)
The total uncertainty derived from contributions of linearity, anisotropy,
frequency response, temperature, relative humidity and with/without
contribution of uncertainty of calibration.
Magnetic probe (1)
Magnetic flux
density
range
Total expanded uncertainty (k=1.96)
Without contribution of
uncertainty of calibration
UT EHP50G (%)
With contribution of
uncertainty of
calibration UTOT (%)
Frequency at 50/60 Hz
50 nT to < 100 µT 2.4 3.1 (2)
100 µT to 3000 µT 2.6 4.3 (4)
Frequency from 5 to 40 Hz 50 nT to 10.0 µT 5.2 5.9 (3)
Frequency from 40 Hz to 100 kHz 50 nT to 10.0 µT 4.8 5.6 (3)
Frequency from 100 to 400 kHz 50 nT to 10.0 µT 7.5 8.1 (3)
(1) This uncertainty budget is for an ambient temperature of (23 +/- 4) °C, and relative humidity of (50 +/- 5) %
The expanded uncertainty for magnetic flux density for values close to 50 nT is calculated with negligible contribution
of noise level.
(2) The expanded uncertainty of calibration UCal used is 2,0%
(3) The expanded uncertainty of calibration UCal used is 3.0%
(4) The expanded uncertainty of calibration UCal used is 3.5%
Electric probe (5)
Electric field
range
Total expanded uncertainty (k=1.96)
Without contribution of
uncertainty of calibration
UT EHP50G (%)
With contribution of
uncertainty of
calibration UTOT (%)
Frequency at 50/60 Hz
1 V/m to 1000 V/m 6.9 7.5 (6)
1 V/m to < 40 kV/m 7.6 8.1 (6)
Frequency from 5 Hz to 100 kHz 1 V/m to < 1000 V/m 8.8 10.3 (7)
Frequency from 100 to 400 kHz 1 V/m to < 1000 V/m 9.4 10.8 (7)
(5) This uncertainty budget is for an ambient temperature of (23 +/- 4) °C, and relative humidity of (50 +/- 5) %
(6) The expanded uncertainty of calibration UCal used is 3.0%
(7) The expanded uncertainty of calibration UCal used is 5.5%

1-6 General Information
1.6.2 Explication Notes
a) If we have the certificate with different values of the uncertainty of
calibration, in order to calculate the total expanded uncertainty UTOT ,
the uncertainty of calibration has to be taken into account:
where is the standard uncertainty
………….
Cal
uis the standard uncertainty
( Cal
u= U Cal / k )
where U Cal is the expanded uncertainty reported on certificate
and k is the coverage factor reported on certificate (normally
k=2 or 1.96)
This quadratic sum is considered a precaution because the
uncertainty Cal
uis added quadratically to an uncertainty that is
already a combined uncertainty.
b) When the environmental temperature is higher than 23 °C, the contribute
due to the temperature can be added quadratically to the uncertainty.
Example: for magnetic measurements, if the temperature is 43°C, we get a
variation of 20°C in comparison to 23°C, corresponding to a variation o
f
0.26 dB ( 0.013 dB / °C ) equivalent to 3,04% and therefore, assuming a
rectangular distribution of probability, the standard uncertainty is 1.755%
( = 0,0304 / 3).
Assuming an expanded uncertainty UTOT =2.4%,
()
042.001755.0
2
024.0
96.1 2
2
≅+






•=
TOT
'U is obtained.
The quadratic sum is considered a precaution because the uncertainty due
to temperature, is added quadratically to an uncertainty that is already a
combined uncertainty.
A
similar calculation can be made in case the relative humidity overcomes
50%.

General Information 1-7
1.6.3 Measurements
Uncertainty of EHP-50G
(Weighted Peak mode)
The total uncertainty derived from typical contributions of linearity,
anisotropy, the worst case deviation from the nominal weighting filter,
temperature and relative humidity.
Magnetic probe
Total expanded uncertainty %
Frequency from 15 Hz to 100 kHz 4.6
Frequency from 10 Hz to 300 kHz 7.1
Frequency from 3 Hz to 300 kHz 8.6
Electric probe)
Total expanded uncertainty %
Frequency from 15 Hz to 250 kHz 8.3
Frequency from 3 Hz to 300 kHz 9.7
Note: below 3 Hz and above 300 kHz the uncertainty increases to 0.85 dB (band limiting filter not considered).

1-8 General Information
1.7 Anisotropy
1) The IEEE 1309 [3] defined the anisotropy (A) as the maximum deviation
from the geometric mean of the maximum response and minimum response
when the probe is rotated around the ortho-axis (e.g. "virtual handle") as
shown in the example in figure below.








⋅
⋅=
minmax
max
10
log20 SS
S
AdB equation (1)
where S is the measured amplitude in field strength units.
2) The IEC 61786 [2] "Measurement of low-frequency magnetic and electric
fields with regards to exposure of human beings - special requirements for
instruments and guidance for measurements" does not define the anisotropy
and suggests, for three-axis probes, the calibration of each axis when each
element is aligned with the incident field.
The calibration should also be checked for a specific orientation where
approximately there is the same indication for each one of the three axis
(XYZ measurement).
Following this suggestion some laboratories find the minimum and the
maximum values of the X, Y, Z and XYZ measure and calculate the
anisotropy using equation (1).
3) We calculated the anisotropy with equation (1) but with 3D mesh
measurements to cover 4πsteradians,that is to say in a much more severe
condition than the orthotropic one.
Fig. 1-2 3D mesh measurements of magnetic probe
Each x marker in the fig.1 indicates the coordinates surface of the spherical
coordinates (r,
θ , ϕ ).
The anisotropy is evaluated with 30 degrees steps for
θ and ϕ , and r
shows the calibration factor at each position.
The typical value of anisotropy is 1,4% (0.12 dB) for magnetic probe and
6,5% (0,54 dB) for electric probe.
The anisotropy calculated in this way is worse respect to other cases above
described and it is more representative of the reality.

General Information 1-9
A good evaluation of the anisotropy of a field probe should be carried out in
a place where all of the following conditions are satisfied:
Far Field
Plane wave
Uniform field
Since the calibration systems are not infinite, these conditions can be
approximated but never reached, and so the evaluation of anisotropy for
our probes shows results worse than the reality. So, the real typical
anisotropy response is better than what specified.
EHP-50G is housed in a small cubic case. The bottom side panel includes
an optical fiber connector, extension rod screw, battery charger connector,
ON/OFF button and Status LED.
Fig. 1-3 EHP-50G axes
The sensitive elements are located approximately 9 mm below the external
surface

1-10 General Information
As depicted above, the magnetic sensor system is composed by three
magnetic loops positioned orthogonal each other. The electric sensor
system is composed by three orthogonal parallel plates capacitors installed
on the opposite side of the magnetic loops.
The geometric structure of the Narda probes, with sensors placed on the
peripheral faces of the cube, shows the same behavior as one with the
sensors accumulated in the center, when measuring far fields.
Moreover, this provides the opportunity to evaluate also very nearby fields,
albeit with all the limitations that this entails, knowing exactly where the
single sensor is, and allowing to minimize the contribution of the others.
References
[1] ISO/IEC “Guide to the expression of uncertainty in measurement” JCGM 100:2008 GUM 1995
with minor correction – International Organization for Standardization.
[2] CEI-IEC 61786-1 ed. 1.0 “Measurement of DC magnetic, AC magnetic and AC electric fields from
1 Hz to 100 kHz with regard to exposure of human beings – Part 1: Requirements for measuring
instruments.
[3] IEEE Std 1309™-2005 (revision of IEEE Std 1309-1996) “IEEE Standard for Calibration of
Electromagnetic Field Sensors and probes, Excluding Antennas, from 9 kHz to 40 GHz”.
[4] EA European co-operation for Accreditation – Public Reference EA-4/02 M:2013

General Information 1-11
1.8 Overload level
Fig. 1-4 Overload level EHP-50G (B Field, RMS)
Fig. 1-5 Overload level EHP-50G (E Field, RMS)

1-12 General Information
1.9 EHP-50G Panel
Fig. 1-6 Panel of EHP-50G
Key:
1. Led
2. Battery charger connector
3. ON/OFF button
4. AUX input connector MMCX
male type
5. Fiber optic connector