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EMSCOPE User’s Manual

1. General Information

1.1 Documentation

Enclosed with this manual are:

  • a service questionnaire to send back to EMZER in case an equipment service is needed (end)
  • an accessories checklist to verify all accessories enclosed in the packaging.

1.2 Introduction to EMSCOPE

Figure 1. EMSCOPE picture.

EMSCOPE is an EMZER’s instrument for ElectroMagnetic Interference (EMI) measurements that combines a 2-channel EMI-Test Receiver with a 16-A single-phase dual-port V-network Line Impedance Stabilization Network (LISN) and two Transient Limiters (one for each channel of the EMI receiver). EMSCOPE has been optimally designed and manufactured to be compliant to CISPR 16-1-1, CISPR 16-1-2 and MIL-STD-461E International Standards for measurements of conducted electromagnetic interference from 9 kHz up to 110 MHz.

EMSCOPE integrates the peak, quasi-peak and average detectors fully compliant to CISPR 16-1-1, which can be run in parallel and real time, considerably reducing the measurement time when compared to any other option. Additionally, it is possible to simultaneously measure the line and neutral emissions, or the common-mode and differential-mode (modal) emissions with the three detectors running simultaneously. Modal-emission measurements are fundamental to know the dominant mode and to implement the suitable power-line filter accordingly, using fewer components and getting a cheaper design.

EMSCOPE can be connected to a LAN or reached by direct connection (using the supplied optical fibre), and it is remotely controlled using any standard web browser, without the necessity of any additional software. The web-based application installed in EMSCOPE exhibits a very friendly and intuitive interface that makes any kind of measurement really easy to configurate.

Important! Before using the LISN, all safety requirements must be fulfilled.

1.3 Instrument Items

EMSCOPE includes the following items:

  • EMSCOPE enclosure containing two EMI-Test Receivers, a 16-A single-phase dual-port V-network LISN and two Transient Limiters.
  • Tp link multimode fiber to Ethernet converter.
  • IEC 20 cable.
  • IEC 14 Cable.
  • SFP Multi-mode optical fiber 50 or 62.5/ 125 LC LC connector (standard 1000BASE-SX). W. length: 850nm.
  • Operating Manual.
  • Certificate of Compliance.
  • Return for Repair form.

1.4 Optional accessories

Additionally to the multi-mode fiber to Ethernet converter, EMZER can supply a multi-mode fiber to USB converter to directly connect the computer to the EMSCOPE. The model supplied is:

  • DIGITUS USB 3.0 Gigabit SFP Network Adapter (Digitus DN-3026) with a fber optics transceiver (Digitus DN-81000).

Important! It is highly recommended to use this option with a USB-3.0 port.

1.5 Other accessories

EMSCOPE can be used with:

  • External LISNs of any type
  • Near Field Probes
  • Current probes

1.6 Main Specifications

Table 1-1 lists the EMSCOPE performance specifications. The following conditions apply to all specifications:

Table 1-1 Main Specifications of the EMI Receiver
Electrical Characteristic Performance Limits
Frequency range / RBW Filter





Resolution / RBW Filter





Frequency accuracy
9 kHz to 150 kHz / 200 Hz
9 kHz to 150 kHz / 1 kHz
150 kHz to 30 MHz / 9 kHz
150 kHz to 30 MHz / 10 kHz
30 MHz to 110 MHz / 120kHz

113 Hz / 200Hz
509 Hz / 1kHz
5087 Hz / 9kHz
5087 Hz / 10kHz
30.52 kHz / 120kHz

≤ 2.5 ppm @operating temperature range
= 1.5 ppm @ 25ºC
RF inputs

VSWR

Attenuator

Transient limiter
ZIN 50 Ω, N fem.

< 1,2

0 dB to 78 dB (1 dB step)

Built in up to 30 MHz.
1dB compression point: 23dBm
Max input level (without equipment damage) 144 dBμV (5W, 37 dBm)
Noise level (Att. 22 dB, 50 Ω term., Hold Time 1 s)

9kHz to 150kHz
(200Hz RBW)

9kHz to 150kHz
(1kHz RBW)

150kHz to 30MHz
(9kHz RBW)

150kHz to 30MHz
(10kHz RBW)

30MHz to 110MHz
(120kHz RBW)



< -9 dBμV (QP)
< -15 dBμV (AV)

Not defined (QP)
< -13 dBμV (AV)

< 7 dBμV (QP)
< 0 dBμV (AV)

Not defined (QP)
3 dBμV (AV)

< 27 dBμV (QP)
< 15 dBμV (AV)
Detectors Peak, Quasi-peak, CISPR Average (all can be run simultaneously on both lines, that is, up to 6 detectors), fully compliant to CISPR 16-1-1
Type of measurements Physical (or circuit, i.e. line and neutral) and modal (common and differential mode) conducted emissions
Full spectrum measurement time Equal to the measurement dwell time, which is totally configurable from 1s to 15s
Display units dBm, dBmV, dBµV, Watts, Volts
Measurement accuracy for sinusoidal signals > 20 dB 9 kHz to 150 kHz / 200 Hz ± 1,0 dB
9 kHz to 150 kHz / 1 kHz ± 1,0 dB
150 kHz to 30 MHz / 9 kHz ± 1,0 dB
150 kHz to 30 MHz / 10 kHz ± 1,0 dB
30 MHz to 110 MHz / 120 kHz ± 1,0 dB
CISPR 16-1-1 conformity Standard compliant QP detector down to 10 Hz PRF

Standard compliant Average detector down to 10 Hz PRF
I/O Interface SFP Optical
Operating temperature 0 °C to 40 °C
Power supply 110-240 VAC. Consumption: 25W max
Dimensions (W x H x D) 252 x 195 x 438 mm
Weight 8.5 kg
Built in LISN Fully compliant to 16-1-2 standards
Frequency range 9 kHz to 30 MHz
Continuous rated output current Up to 16 A @ 230 VAC (socket dependent)*
Max permissible operating voltage Up to 300 VAC – 325 VDC (socket dependent)*
EUT supply frequency range DC to 60 Hz
CISPR equivalent circuit / Pre-filter Choke 50 Ω / / (50 μH + 5 Ω) / 250 μH
EUT Power connector / mains Schuko socket (Type F) / IEC C20
Artificial Hand / connector type 510 Ω + 220 pF / 4 mm socket

* Examples of sockets:

  • NEMA 5-15R: 15A / 125Vac
  • EU Type F: 16A / 230Vac
  • GB BS1363 Type G: 13A / 250Vac

1.7 Front Panel

The front panel of the EMSCOPE is shown in the next figure.

Figure 2. Front panel.

Connectors and indicators of the front panel from top to bottom:

  • LEDs
  • RF input 50 Ω connectors

The equipment has 2 N female RF input 50 Ω connectors that permits the equipment to simultaneously measure 2 RF signals. Each RF input is internally protected from transient voltages by means of a transient limiter. The technical characteristics are described in the Main Specifications section.

  • RF output connectors

The equipment has 2 N female RF output connectors. Each connector is the output of a channel of the artificial mains network (LISN). These connectors output the conducted interferences generated by the equipment under test and provide the means to measure them.

  • Output mains power network supply socket

This socket is the output of the artificial mains power network of the LISN. It is the mains socket where the equipment under test must be connected to allow the measurement of its conducted emissions. The technical specifications of the LISN and its power handling capabilities are described under the Main specifications section.

  • Artificial Hand 4mm socket

This socket provides the RC network required to mimic the behaviour of a hand for a handheld equipment under test, as stated in the CISPR 16-1-2. This RC network is described in the Main Specifications section.

  • Protective earth terminal. It is a M6 threaded bolt for connecting the protective earth conductor.
  • Additionally, there exist two 4mm female sockets for connecting the reference ground during calibration.

1.8 Rear Panel

The rear panel of the equipment is shown in the next figure:

Figure 3. Rear panel.

Connectors of the rear panel from top to bottom:

  • SFP connector. The installed SFP transceiver is described in the Instruments Items section.
  • Instrument power supply socket. It includes fuses and the On-Off switch.
  • IEC-20 socket. It is the socket of the mains power supply that cross the LISN and feeds device under test.
  • Grounding bar. This bar provides an appropriate RF ground reference and it should be connected to the grounded RF plane as described in different standards ( e.g. CISPR 16-2-1).
  • Additionally, there exist two 4mm female sockets for connecting the reference ground during calibration.

1.9 EMSCOPE Overview

The EMSCOPE features a completely new receiver architecture based on the most recent FPGA technology that includes a two port CISPR 16-1-2 LISN and two 10-dB transient limiters, and has been designed to be controlled using only a web browser, independently of the operating system and platform. No additional software is required.

In the CISPR bands A (9 kHz ÷ 150 kHz), B (150 kHz ÷ 30 MHz) and C (30 MHz ÷ 110 MHz) the standards require the use of specially shaped 200-Hz, 9-kHz and 120-kHz filters respectively (1-kHz and 10-kHz filters in the MIL-standard case). EMSCOPE makes use of internal numerically modelled filters in compliance with the norms, using FFT and signal processing techniques, which allows to perform compliance measurements with both standards (CISPR and MIL). Besides, it can provide simultaneous and real-time measurement results using the fully-compliant-to-CISPR-16-1-1 peak, quasi-peak and average detectors.

The fully-compliant-to-16-1-2-standard LISN integrated in the instrument allows performing conducted-emission measurements without the necessity of any other device, making of EMSCOPE a Fully Measurement Setup. Additionally, it can also be easily connected to other external LISNs, using its external N connectors, to perform EMI measurements according to any other standard. Thanks to its architecture and to the large internal computation capability, the EMSCOPE can perform a precise entire band test in a extremly short time. This feature is not only useful to greatly increase the productivity of the test lab, but also to make better and more comprehensive analysis in case the disturbance to be evaluated is somehow intermittent and with an irregular repetition rate. Since it is possible to perform a modal analysis of the interference, providing the common-mode and differential-mode measurements, it is really easy to design a suitable power-line filter for the EUT.

2. Safety information

2.1 General safety information

Never remove the cover or any part of the housing. During operation, there exists accesible parts with DANGEROUS voltages inside the unit.

Do not insert any objects into the openings of the housing that are not intended to that purpose. This can cause short circuits inside or electric shocks/injuries.

The unit is not protected agains the penetration of liquids. Do not close any of the openings needed for ventilation.

Since the ventilation air flows from the botton side, the unit must be placed on a nonflammable base in order to prevent a fire in case of overheating.

2.2 Safety information regarding the Line Impedance Stabilization Network (LISN)

Important! Over current protection is not provided. The LISN must be connected to a power mains which has an appropiately rated mains protection installed.

Important! Before putting into service ensure that:

  • An additional PE conductor is connected (see next paragraph)
  • The ventilation openings are unobstructed

Important! Earth connection: Precautions must be taken because, since the LISN is compliant to CISPR 16, it can not inherently adhere to the permitted leakage current limit value according to EN 61010-1 and basic insulation of a protection class I. Due to this inherent high leakage current to ground of this kind of equipment an additional protective earth connection must be supplied prior connecting the unit to the mains power supply. For this purpose, the equipment is provided with an earth grounding bar at the rear panel and additionally a protective earth screw is provided at the front.

In addition, due to this high leakage current (above 1 A), it is not possible to use a residual current operated circuit breaker. It is strongly recommended to use an isolating transformer.

A long-term operation with maximum load, the surface of the unit may become >60 ºC.

3. Installation

3.1 Introduction

This section provides the information needed to install your EMSCOPE. It includes the information pertinent to initial inspection and power requirements, connections, operating environment, instrument mounting, cleaning, storage and shipment.

Important! Before connecting the equipment follow the provided Safety information section. Not following it can result in important damages, serious injuries and death.

3.2 Initial Inspection

When receiving the equipment, first inspect the shipping box for any damages. If the shipping box is damaged, it should be kept until the contents of the shipment have been checked for completeness and the instrument has been checked mechanically and electrically.

3.3 Packing and Unpacking

Verify the availability of all the shipped items with reference to the shipping check list enclosed with the User Manual. Notify any damage to the forwarder personnel as well as to your EMZER Representative.

To avoid further damage, do not turn on the instrument when there are signs of shipping damage to any portion of it.

3.4 Preparation for Use

The EMSCOPE EMI Receiver is a Safety Class I apparatus, and it is also equipped with protective/functional earth terminals on the rear and front panels. A good safety/functional ground connection should be provided before to operating the system.

Important! The EMSCOPE LISN constructed according to the standard CISPR 16 can NOT comply with the permissible leakage current limit stated in the IEC 61010 for a class I equipment. The instructions provided in the Safety Information section must be followed.

3.5 Power Supply

The universal adapter supplied with the receiver can work at either 50 Hz or 60 Hz with a supply voltage rated between 100 and 240 Volt. When the power supply is switched ON, the green led lights up. After about 45 seconds (depending on the network status) since the power has been switched on, the EMSCOPE is ready for use.

3.6 Environment

The operating environment of the receiver is specified to be within the following limits:

  • Temperature : 0 °C to +40 °C
  • Humidity : < 85% relative LISN; < 95% relative EMI receivers
  • Altitude : 3000 meters

The instrument should be stored and shipped in a clean, dry environment which is specified to be within the following limitations:

  • Temperature : -40 °C to +50 °C (-40 °C to +40 °C for long periods)
  • Humidity : < 95% relative (< 80% relative for long periods)
  • Altitude : 15000 meters

3.7 Return for Service

If the instrument should be returned to EMZER for service, please complete the service questionnaire enclosed with the User Manual and attach it to the instrument.

To minimize the repair time, be as specific as possible when describing the failure. If the failure only occurs under certain conditions, explain how to duplicate the failure.

If possible, reusing of the original packaging to ship the equipment is preferable.

In case other package should be used, ensure to wrap the instrument in heavy paper or plastic.

Use a strong shipping box and use enough shock absorbing material all around the equipment to provide a firm cushion and prevent movement in the shipping box; in particular protect the front panel.

Seal the shipping box securely.

Mark the shipping box FRAGILE to encourage careful handling.

3.8 Equipment Cleaning

Use a clean, dry, non-abrasive cloth for external cleaning of the equipment.

To clean the equipment do not use any solvent, thinner, turpentine, acid, acetone or similar matter to avoid damage to external plastic or display surfaces.

3.9 Equipment Ventilation

To allow correct equipment ventilation, ensure that the vent grids on the side and on the bottom of the equipment are free by any obstructing object.

3.10 Hardware Installation

EMSCOPE is delivered from factory ready to use. After removing the instrument from its cardboard shipping box, the user must perform the following connections before switching it on:

  1. Connect EMSCOPE to the suitable networking technology. To this end, connect a multimode fibre from the EMSCOPE’s SFP port to the SFP port of the user’s media converter module. And then, connect the user’s media converter module to one of the following options:
    1. The user’s Local Area Network (LAN), using a UTP Ethernet cable. In this case, the media converter module is a Gigabit Ethernet Media Converter. An example (among others) of such converter is: tp-link MC220L.
    2. The remote computer (direct cable connection). In this case, the media converter module is a Fibre Optic Converter that is directly connected to the computer. An example (among others) of such converter is: US1GA30SFP from Startech.com, that directly connects to the computer’s USB port.
  2. Connect the instrument to the power-line network from the rear panel. Be sure to use the IEC 14 cable on the mains socket called “LINE”. The mains socket called “EUT POWER INPUT” needs an IEC 20 cable and does not supply power to the EMSCOPE.

After having done these connections, the instrument can be switched on using the Power button properly. When doing this, the front green led lights up to indicate the instrument is correctly powered.

During a few seconds, the EMSCOPE boots and runs the firmware which manages the receiver. Once the web server is ready, the yellow led is switched on, informing that the receiver is ready to use.

3.11 Web Connection

3.11.1 Dynamic configuration

EMSCOPE is a network attachable device focused on simple connectivity and quick accessibility, and it does not require the installation of any additional software:

  • When connected to a typical LAN where there is a DHCP server (i.e. a router), EMSCOPE will automatically acquire an IP address.
  • If the direct cable connection option is opted, or the LAN has no DHCP server, EMSCOPE will automatically assign itself an IP address (it uses the IPv4LL, «Dynamic Configuration of IPv4 Link-Local Addresses» -IETF RFC3927- protocol).

In either case, the user will be able to access the device by its MDNS name. To this end, open the web browser in the remote computer and type the following address in the URL field:

http://emscope-xxxx.local/

where xxxx are the last 4 characters from the SN of your EMSCOPE. The SN is provided in the rear panel. Alternatively, if known, the IP address can also be directly written in the URL field. After the last step you will get the EMSCOPE main page as shown below.

Figure 4. EMSCOPE main’s page.

3.11.2 Static Configuration

If the user wants to set the IP, it can be done in the configuration interface. To this end, click on the “Device Configuration” tab, and then “Network Configuration”. Alternatively, the same webpage is reacheable by typing the following address in the URL field:

http://emscope-xxxx.local/ipconfig.php

where xxxx are the last 4 characters from the SN of your EMSCOPE. The SN is provided in the rear panel. The network configuration interface opens. By selecting the “Static IP configuration” option, an appearance similar to the interface shown in Figure 5 is obtained. The desired network configuration can be introduced following the described indications.

Figure 5. Network configuration interface.

Allowed static IP addresses are limited to class A and C.

Table 2-1 Private IP Addresses
Class Private Network Subnet Mask Address Range
A 10.0.0.0 255.0.0.0 10.0.0.1 - 10.255.255.254
C 192.168.0.0 255.255.0.0 192.168.0.1 - 192.168.255.254

3.12 Using the Line Impedance Stabilization Network (LISN)

Important! Before using the EMSCOPE's built-in LISN, follow the provided Safety information. Not following it can result in important damages, serious injuries and death.

EMSCOPE must be bonded to the Protective Earth (PE) using the grounding bar placed in the rear panel. In case of using an external LISN, both need to be connected to the same PE.

To connect the EMI receivers to the built-in LISN for conducted interference measurements of an EUT, use the two N-connector bridges provided to connect the RF outputs of the LISN to the RF inputs of the receiver.

In order to avoid the unwanted tripping of the protection devices (due to the high leakage current inherently present in the LISN due to its construction made according to CISPR 16-1-2), an insulation transformer shall always be used between the mains supply and the LISN.

3.13 Transient Limiters

The built-in transient limiters are used to protect the input of the receiver from transient over voltages. Sometimes, the conducted disturbances entering the receiver through the LISN are too high - even if they cannot be seen on the EMSCOPE because they are out of the measurement bandwidth - and the associate energy is high enough to damage the input circuit. Two transient limiters (one for each line) are integrated in the system as a protection of the input from unexpected pulses and transients.

The maximum input level that the Transient Limiter support without equipment damage are 5 W (or, equivalently, 144 dBμV or 37 dBm, considering an input impedance of 50 Ω).

4. EMI Receiver Operating Instructions

This section introduces the instrument interface, describes some important parameters that must be known for a suitable configuration of the instrument, and explains its main utilities.

4.1 Introduction

The EMSCOPE EMI Receiver is connected using a web browser as described above. The first time a user connects to the EMSCOPE (or when connecting using a clean session), a measurement with the default configuration is provided: one single trace measuring channel 1 (Line), RBW at 9kHz, Span 150 kHz – 30 MHz, Peak detector, Ref. Level at 100 dBμV, automatic attenuation, among other configurations.

The interface of the web app is shown in Figure 6. This interface has three important blocks. The red one contains the Main Menu, where the function keys are displayed. Each function key opens a submenu with the Action List (orange block), that is, all those settings that the user can configure for that function key. Each modification will be reflected in the Measurement Plot (blue block).

Figure 6. Web app interface.

Placing the mouse cursor above the name of the trace, the most relevant information regarding the measurement is provided, so the user can easily know what kind of measurement is currently configured. Information regarding the Center Frequency, Span and amplitude levels are reported on the top right corner.

If the user modifies the measurement configuration and closes the session, next time the user connects again to the EMSCOPE, the last configuration before closing is recovered.

Next Sections relate important considerations for the measurements and describe the relevant settings of the function keys.

4.2 Overload

For a correct measurement, be sure not to overload the EMSCOPE. Input attenuation must be properly configured considering the maximum amplitude expected at the input ports. Table 3-1 shows the maximum amplitude values that should be measured for each attenuator value to avoid distortion. If the signal surpasses this value, the EMSCOPE is saturated and will not present correct measurement values.

Important! Carefully consider that:

  • Although EMSCOPE does not show any frequency bin with an amplitude value above the levels shown in Table 3-1, it may become saturated if the time-domain representation of the measured spectra is above them (saturation is produced in the ADC before processing the input signal). When this happens, a warning message is displayed in the measurement.
  • Signals above 20 dBm will not be correctly measured in any case due to the activation of the transient limiters, clipping the input signal.
  • Signals above 37 dBm (5 W) are not supported by the transient limiters and will damage the receivers.
  • In case that an OVERLOAD indication occurs when using maximum attenuation, it is necessary to add an external attenuator to carry on the measurement without overpassing the declared limit. The user can use the “External Loss Attenuation” option to compensate the additional losses.
Table 3-1 Maximum amplitude values
Attenuator value (dB) Maximum Amplitude (dBm) Maximum Amplitude (dBμV)
0 -28 79
1 -27 80
2 -26 81
3 -25 82
4 -24 83
5 -23 84
6 -22 85
7 -21 86
8 -20 87
9 -19 88
10 -18 89
11 -17 90
12 -16 91
13 -15 92
14 -14 93
15 -13 94
16 -12 95
17 -11 96
18 -10 97
19 -9 98
20 -8 99
21 -7 100
22 -6 101
23 -5 102
24 -4 103
25 -3 104
26 -2 105
27 -1 106
28 0 107
29 1 108
30 2 109
31 3 110
32 4 111
33 5 112
34 6 113
35 7 114
36 8 115
37 9 116
38 10 117
39 11 118
40 12 119
41 13 120
42 14 121
43 15 122
44 16 123
45 17 124
46 18 125
47 19 126
48 20 127
49 20 127
50 20 127
51 20 127
52 20 127
53 20 127
54 20 127
55 20 127
56 20 127
57 20 127
58 20 127
59 20 127
60 20 127
61 20 127
62 20 127
63 20 127
64 20 127
65 20 127
66 20 127
67 20 127
68 20 127
69 20 127
70 20 127
71 20 127
72 20 127
73 20 127
74 20 127
75 20 127
76 20 127
77 20 127
78 20 127

4.3 Reference Level

The Reference Level sets the top magnitude value of the Measurement Plot. It can be configured in the tab Amplitude from the Main Menu. If the Input Attenuator is configured in the Automatic mode, the Reference Level automatically fixes the Attenuator value according to Table 3-1. By moving the measured signal close to the Reference Level (without overpassing it and always avoiding an overload), the best possible exploitation of the ADC's dynamic range is accomplished, obtaining more accurate measurements.

If the Input Attenuator is not set to Automatic mode, the Reference Level setting is decoupled from the input gain, which means that the gain (or attenuation) remains constant; in such cases, changing the Reference Level only influences the representation of the signal on the display through numeric scaling.

4.4 Dwell Time

The dwell time can be found in the tab Sweep from the Main Menu. This value, expressed in seconds, defines the time that the detectors are measuring the input signal. Since all frequencies are measured simultaneously, the measurement time is equal to the dwell time. Therefore, a dwell time of 2 seconds means that the measurements are performed for 2 seconds. In addition, because the equipment is continuously measuring, the magnitudes are refreshed every 2 seconds.

4.5 Traces and Detectors

EMSCOPE has been designed to allow the use up to six simultaneous detectors: two Peak, two Quasi-Peak and two Average detectors (one of each for each input line). Quasi-Peak and Average Detectors have been implemented to meet CISPR 16-1-1 Standard. All six detectors run in real time. The detectors can be selected in the tab “Trace configuration” from the Main Menu.

Each detector has its own trace. A new trace (or tab) can be opened clicking on the symbol (located just after the name of the last opened trace). Up to six traces can be opened simultaneously. Although all active traces are displayed simultaneously, they can also be hidden by clicking on the eye symbol (located just before the name of the trace): .

4.5.1 Peak Detector

This detector gives the maximum level observed in each measured spectral line during the configured measurement time (dwell time).

This detector is calibrated to give the rms value of an unmodulated sinusoidal signal.

For unmodulated signals, dwell time can be configured as low as possible. For modulated o pulsed signals, the dwell time must be configured to record at least one period or pulse of the signal.

4.5.2 Quasi-Peak Detector

This detector gives the maximum level observed at each weighted spectral line. The spectral lines have been weighted according to CISPR 16-1-1. Depending on the selected frequency band, the detector is automatically configured to meet CISPR 16-1-1 specifications. It is calibrated to give the rms value of an unmodulated sinusoidal signal.

This detector involves long measurement times (dwell time). For CISPR 16 band A (9-150kHz) at least a dwell time of 2 seconds must be configured. For CISPR 16 band B (150kHz-30MHz), at least a dwell time of 1 second must be configured. This guarantees a correct weighting of pulsed signals with repetition frequency as low as indicated in the specifications. For unmodulated signals or faster repetition frequencies, lower dwell time can be configured.

4.5.3 CISPR Average Detector

This detector gives the weighted average level of each measured spectral line. The spectral lines have been weighted averaged according to CISPR 16-1-1. The average detector is useful to measure narrowband signals to overcome problems associated with either modulation content or the presence of broadband noise. The CISPR average detector is calibrated to give the rms value of an unmodulated sinusoidal signal.

In order to perform the correct weighting of the signal, the dwell time have to be configured long enough. For unknown signals, at least a dwell time of 1 second must be configured. This guarantees a correct weighting of pulsed signals with repetition frequency as low as indicated in the specifications.

4.6 RBW Filters

The Resolution Bandwidth is used to select the bandwidth of the measuring filter. It is found in the tab Trace from the Main Menu. The drop-down menu allows the user to select between the CISPR bandwidths 200 Hz, 9 kHz and 120 kHz, or the MIL bandwidths 1 kHz and 10 kHz. These filters are mathematically modelled using digital techniques to be compliant to the two standards (CISPR 16-1-1 and MIL-STD-461E) Band A, B and C.

4.6.1 Single-Band Measurements

When selecting the 200-Hz or 1-kHz bandwidth filter, measurements are provided up to 150 kHz (Band A). When selecting the 9-kHz or 10-kHz bandwidth filter, measurements are provided up to 30 MHz (Band B). When selecting the 120-kHz bandwidth filter, measurements are provided up to 110 MHz (Band C).

4.6.2 Dual-Band Measurements

It is possible to show measurements using two different RBW filters simultaneously. The two possibilities are:

  • CISPR bandwidths 200 Hz and 9 kHz.
  • MIL bandwidths 1 kHz and 10 kHz.

When selecting this option, measurements from 9 kHz up to 150 kHz (band A) are done with the smaller filter (either 200 Hz or 1 kHz), and from 150 kHz to 30 MHz (band B) are done with the highest filter (9 kHz and 10 kHz).

4.7 EMI and Modal Measurements (Channel)

EMSCOPE can measure line and neutral simultaneously using the three detectors for each one (that is, six detectors running simultaneously in six different traces). This is called here EMI measurements. Alternatively, modal measurements (that is, common-mode and differential-mode emissions) can also be done instead of line and neutral, using the same six detectors.

The selection between EMI and modal measurements can be done in the tab Trace Configuration from the Main Menu. L-G and N-G are the line and neutral measurements respectively. CM and DM are the common mode and differential mode respectively. It should be noted that line and neutral measurements are only done when the “EMI measurement” button is selected. Otherwise these measurements remain in a paused mode. In the same way, common-mode and differential-mode measurements are only done when the “Modal measurements” button is selected. Otherwise these measurements remain in a paused mode. The reason for that is that the same six detectors (two peak, two quasi-peak and two average) are shared between the physical and modal emissions, so that when one of them is selected, the other cannot be measured.

4.8 External Loss Attenuation

Losses added by external components of the measurement setup can be introduced to be considered in the measurement. External losses can be introduced and activated in the tab “Amplitude”. The user can create a table defining the external losses at different frequencies (at least two frequency points are needed). The software interpolates the table when doing the measurements so that each frequency bin is compensated suitably. To consider the external losses in the measurement plot, the option “Activate external loss attenuation” must be selected.

4.9 Utilities

4.9.1 Options overview

EMSCOPE interface has been designed to provide an optimal user experience and usability. To this end, all options have been grouped so that any measurement can be configured with the minimum number of clicks.

  • Frequency and Amplitude tabs group all options that affect all measurements (or traces) that are displayed simultaneously. By modifying either the frequency band, the start, center and stop frequency, the sweep and dwell time, the reference level, the input attenuator, the units or the external loss attenuation, all measurements will be updated accordingly.
  • Trace configuration, on the other hand, groups all options that affect only the active trace. In this tab, the user can configure the trace type, the channel and the detector. Each trace can be configured independently of the other traces. The only exception is the EMI or Modal measurements selection.
  • Analyse contains all those options that allow to obtain a deeper analysis of the measurement plot: Markers, Multi-markers, peak search and delta marker.
  • Limits and Report allows plotting standarized (or, if desired, customized) emission limits to compare the measurements, and generating reports in pdf format.
  • Save & Load allows exporting and importing measurements in different formats.
  • Presets allows reloading measurement configurations.
  • Device configuration provides information of the EMSCOPE such as MAC address, IP address, serial number, software version and temperatures. It allows modifying the interface colors, the network configuration or updating the device.

4.9.2 Zooming into the diagram

The user can zoom into the diagram to visualize the measurement results in greater detail.

This can be done in several ways:

  • Using the soft keys “Zoom in” and “Zoom out”, that can be found in the Action List from the tab “Frequency”.
  • Modifying the span value, in the Action List from the tab “Frequency”.
  • Modifying the “Center”, “Start” and “Stop” values, in the Action List from the tab “Frequency”.
  • Clicking directly in the Measurement plot with the left button of the mouse and, without releasing it, dragging the pointer horizontally (for a zoom into a frequency band) or vertically (for a zoom into an amplitude zone). Full span can be recovered by clicking twice on the Measurement plot.

4.9.3 Markers

Markers are available in the tab “Analyse”. To add a marker in the Measurement Plot, the user has either to write the frequency in the form of the Action List or select it by clicking on the desired position of the Measurement Plot or use the “Pk search” option that will look for the highest peak of the active measurement. Finally, click on the “New Marker” button to add the marker.

Normal markers and Multi-trace markers

There are two types of markers: normal markers and multi-trace markers. Normal markers are placed only on the active trace. Multi-trace markers are placed on all traces simultaneously.

Delta marker (Action List) allows to compare the distance in frequency and amplitude between two markers. Besides, a Delta Table is automatically shown below the measurement plot to show all amplitude marker deltas.

4.9.4 Limits

Users can add and delete their own standard limits to compare the measurements with them. Since limits are usually stablished in a logarithmic sweep, when any standard is plotted, the measurement plots jump (if not already) to logarithmic scale.

4.9.5 Report

This option allows to introduce the conditions of the measurement setup and the suitable parameters to automatically find the highest emission levels.

In the Setup Description the user can add information that will appear in the final report .

The button “Generate list” plots a list with the highest emission levels of the measurement. The number of peaks that will appear depend on three parameters:

  • The Number of Subranges is used to divide the spectra in equidistant ranges. In each one of this ranges the algorithm only shows a fixed number of peaks. The more the subranges introduced, the more peaks that may be shown.
  • The Margin (dB) value is a parameter that is only considered when there is a limit ploted along with the measurement. In that case, EMSCOPE automatically provides a list of all the emission peaks that are above the limit or close below by the margin value. If all emissions fall below this margin, the user will receive an empty list. In order to include emissions far below the limit, the margin must be increased so that it covers the distance between the emissions and the limit. For instance, if there is a peak 20 dB below the limit and it is desired to have it automatically in the output list, the margin should be 20 dB at least. If there is no limit, the Margin (dB) value is skipped and the software shows the maximum number of “highest emissions” it is able to find.

When clicking on “Generate Report”, measurement results are summed up in a report that can be downloaded in a PDF format file. The user is free to add a Logo in the document.

4.9.6 Offline Mode

Measurements can be downloaded in ZIP file, containing an HTML that can be opened in a browser without having to be connected to EMSCOPE, allowing further data analysis. The interface will still allow limited functionality, such as using markers or zooming the plot.

This option can be found in “Standard & Report” → “Download offline version”.

4.9.7 Measurement download in CSV format

Measurements can be downloaded in a comma-separated values (CSV) format to be opened in any operating system using LibreOffice, Office or Google Docs, among others.

This option can be found in “Standard & Report” → “Download measure in CSV”.

5. Applications

5.1 Conducted Emissions

All electric and electronic devices are potential generators of EMI. The term EMI thus refers to the unintended electromagnetic energy emitted by a device which propagates itself along cables or through the air and couples with other devices that are present in the surroundings. These electromagnetic fields (conducted or radiated interference) may generate interfering currents and voltages into nearby equipment and therefore can cause possible malfunctions. In order to prevent and control such interference there are a number of national and international standards, like IEC, which specifies limits and methods of tests. Moreover, within the European Union the application of several European Norms on Electromagnetic Compatibility is enforced by law and therefore the commercialization and use of all the electric and electronic equipment is subject to the measurement of the EMC characteristics, which must be within well-defined limits.

The conducted emissions are the noise currents and voltages that propagate through the power cord or harness to other components/systems or power grid. The EMI currents (or voltages) of the two conductors relative to each other and with reference to the ground form a vector system where two kind of currents (or voltages) are present. They are:

  • The differential-mode noise (DM), defined as the noise that appears across power supply lines and is in series with the power supply line, and the noise current flows in the same direction as the power supply current (Figure 7.a).
  • The common-mode noise (CM), defined as the noise current that has leaked via a stray capacitance through ground and returns to the power supply line (Figure 7.b).

Figure 7. Modal definition of interference: (a) DM. (b) CM.

To reduce the conducted emissions a power-line filter needs to be placed between the power-line terminals and the Equipment Under Test (EUT). In its simplest structure, it contains a X capacitor between line and neutral to mitigate the DM and a CMC and two Y capacitors from line to ground and neutral to ground to mitigate the CM.

Figure 8. Power-line filter components.

Therefore, since these filter components only have effect on one of the modal components (either CM or DM), it is important to measure the modal interference components in order to build a suitable power-line filter. Thanks to the simultaneous measurement of the line and neutral terminals, EMSCOPE is able to recover and provide the measurements of the modal emissions.

5.2 Measurements According to Standards

The design approach adopted for EMSCOPE is that the instrument shall be innovative, fully compliant with the relevant standards and at the same time simple and reliable to use, to be the base building block for any possible conducted-emissions system to measure and evaluate any electric or electronic device from the very first design stages to the final certification.

The need to precisely measure the conducted EMI noises forces the equipment manufactures to use reliable equipment to verify the limits imposed by the relevant standards and/or enforced by local rules. In this view the EMSCOPE receiver is the ideal solution from prototype debugging to final certification, as it fully meets all the performance criteria dictated by these standards, although it remains compact, lightweight and very easy to use. The simple connection by means of a web browser permits an immediate use of the instrument without any training or special difficulties: the operator can concentrate just on analysing the measurement results.

The EUT must be installed according to the procedures indicated in the constructor’s manual and normal operating conditions respected.

5.3 Measuring the EMI Voltage

ElectroMagnetic Interference (EMI) voltage measurements on power supply lines or on signal lines are carried out by means of “Coupling Networks” (e.g. LISNs) or other transducers (e.g. voltage probes). The frequency range is dictated by the applicable standard, which goes from 9 kHz to 30 MHz in most commercial applications.

5.3.1 Measuring principle with a LISN

Important! Before using the LISN follow the provided Safety information. Not following it can result in important damages, serious injuries and death.

Any LISN has three main objectives:

  1. To present a constant impedance to the power input of the EUT, in order to get repeatable measurements of the EUT noise present at the LISN measurement port.
  2. To prevent the high-frequency noise of the power source from coupling in the system. A LISN functions as a low pass filter, which provides high impedance to the outside RF noise while allowing the low-frequency power to flow through to the EUT.
  3. To couple the high frequency noise signal emitted by the EUT to the input of the measuring equipment (EMSCOPE receivers).

The LISN from EMSCOPE has been designed under the CISPR 16-1-2 standard for evaluating and characterizing the operation of the EUT. It is a V-type Network with an impedance of 50 Ω/50 μH + 5 Ω. The schematic of this LISN can be seen in Figure 9. It includes additional capacitors and inductors for filtering and has an operating frequency range of 9kHz to 30MHz.

Figure 9. Schematic of the EMSCOPE’s LISN.

5.3.2 Test Setup according to CISPR 16-2-1

Figure 10 shows an example of the test setup for RFI voltage measurement according to CISPR 16-2-1. The EUT is placed on the top of a table at 0.8 m from a horizontal earthed conducting surface, and at 0.4 m from a vertical earthed conducting surface.

The LISN shall be bonded to the reference conducting surface.

A Floor standing EUT is placed 0,1 m above a horizontal earthed conducting surface of at least 2 m x 2 m in size. This size shall be exceeding by at least 0,5 m the projection of the EUT on the conducting surface.

The power cable (IEC 14 in this case) should be 1m long; longer cable should be centrally bundled for at least 40 cm.

DUTs without a PE (Protective Earth) conductor and manually operated DUTs shall be measured in conjunction with an auxiliary screen or an “Artificial Hand”, as duly specified in the relevant standards.

All the details and information on the test setup are written on the latest version of the applicable Standard.

Figure 10. Test setup for RFI voltage measurement.

5.3.3 Guidance on a preliminary Measuring Procedure for Band B

A step-by-step example of a conducted test manually performed is the following:

  1. Switch ON the EMSCOPE and connect to it as described above.
  2. Introduce a Reference Level between 110 and 125 dBµV and a RBW of 9 kHz selecting the proper frequency measurement range inside the Span menu. Adjust the Scale/Div to 10 dB.
  3. Set the Input attenuator to Automatic mode.
  4. Introduce a Span between 150 kHz and 30 MHz (check the Common values option).
  5. Set the dwell time to 2 seconds.
  6. Open as many traces as detectors desired and select the suitable one in each of them (for instance, peak and average detectors).
  7. Select L-G or N-G measurement in each trace (if both are desired, do it in different tabs).
  8. Go to Standard & Report Tab and find the desired standard. If it doesn’t exist, generate a new one. After this, check Plot standard to see the limits in the measurement graphic.
  9. Connect the two outputs of the LISN to the two RF inputs of the EMI receiver using the N bridges.
  10. With the EUT switched OFF, check that the ambient RF disturbances are at least 20 dB below the desired limit of emissions. If the ambient noises are low enough continue to the next step, otherwise take all the necessary steps to reduce the ambient disturbances (e.g. go to a shielded room).
  11. Switch ON the EUT and wait for the measurement (the measurement time is equal to the dwell time, in this case, two seconds).
  12. Adjust the Dynamic Range and the Reference Level to the most convenient visualization.
  13. If the results are satisfactory, press the button Generate list to list the conflictive emissions.
  14. Press the button Generate Report to obtain an automatic report of the measurements.

5.3.4 Remarks and Hints for Measuring

To avoid errors caused by ambient interference, measurements should be carried out inside a properly shielded room. Different sites, like basements or other rooms with low ambient interference, are often enough for a preliminary evaluation.

Conducted measurements do not strictly require any anechoic environment.

6. Updating Firmware and Software

To update the firmware, access the main interface, go to “Device configuration” and click on “Update Device”; optionally type the following address in the URL field:

http://emscope-xxxx.local/update.html

where xxxx are the last 4 characters from the SN of your EMSCOPE. The SN is provided in the rear panel. A web interface similar to that shown in Figure 11 appears.

If EMSCOPE has access to http://emzer.com/, the user will be notified and prompted to update the device automatically once the user authorizes it.

If the EMSCOPE can’t reach the Internet, the user can manually download the latest firmware image from http://emzer.com/updates and upload it to the EMSCOPE by clicking on the “manual update” link and selecting the update file with the “Choose File” button.

Figure 11. Web interface for an image updating.

7. Remote control

The EMSCOPE software consists in a WebSocket server listening on port 8010 of the machine, and a web server listening on the standard http port 80 that serves the frontend html and related files.

For users that want to write an application for automatic configuration and measurements, EMZER provides the WebSocket API specification (PDF), and a Javascript API that includes an implementation and example.

8. Maintenance

Maintenance of the equipment is limited to external components such as cables.

During operation, inside the equipment there are DANGEROUS voltages that could be contacted. To prevent electrical shock, do not open the equipment.

Clean the exterior of the equipment using a damp cloth and mild cleaner. Always unplug the unit before cleaning.

Product may be opened only by authorized, specially trained personnel. Before performing any work on the unit, this must be disconnected from the mains. Only technical personnel authorized by EMZER can perform any adjustments, replacement of parts or repair.

Service Questionnaire

Dear Customer,

Thank you for purchasing an EMZER’s product. You now own a high-quality instrument that will give you many years of reliable service. EMZER recognizes the importance of the Customer as reason of existence; in this view, any comment and suggestion you would like to submit to the attention of our service organization is kept in great consideration. Moreover, we are continuously improving our quality, but we know this is a never-ending process. We would be glad if our present efforts are pleasing you. Should one of your pieces of EMZER equipment need servicing you can help us serve you more effectively filling out this card and enclosing it with the product. Nevertheless, even this product will eventually 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 EMZER Sales Partner or by visiting our website at www.emzer.com.

Service needed

  • Unordered List ItemCalibration only
  • Repair
  • Repair & Calibration
  • Certified Calibration
  • Other

Company:

Address:

Technical contact person:

Phone number:

Equipment Model:

Serial Number:

Accessories returned with unit:

  • None
  • Cable(s)
  • Power cable
  • Other:

Observed symptoms/problems:

public/emscope/user_manual.txt · Last modified: 2020/09/08 16:45 by admin