Overview
The A200-2 Set consists of two sensors which allow for potential free transmission of analog signals under EFT/ESD/RF interference. The signals are displayed on an oscilloscope. Disturbed signals can be easily detected. In the device under test the sensor transforms the measured logic signals into optical signals. The optical signals are transmitted via a fibre optical cable to the optical receiver which transforms them into electrical signals. These can be seen with an oscilloscope or can be used for controlling other devices. The system is suitable for monitoring signals or devices under test in an anechoic chamber or for EMC optimizing of hard- and software.
Scope of delivery
2x AE 200, Optical Receiver
2x AS 200, Optical Sensor (50 / 10) V DC
2x LWL Ø 2.2 mm 6 m, Optical Fibre, Single 6 m
1x NT FRI EU, Power Supply Unit
1x A200-2 acc, Accessories
1x A200-2 case, System Case
1x Analog m, User Manual
Additional sensors are available on request and can be added to the set.
| Technical Parameters | |
| Bandwidth | DC ... 500 kHz |
| Sampling rate | 3 Msps |
| Resolution | 12 Bit |
| AE 200 Optical Receiver | |
| Bandwidth | DC ... 500 kHz |
| Voltage range - output | 0 V ... 10 V |
| Optical input: Optical fiber | Ø 2.2 mm |
| Supply voltage | 12 V ... 16 V |
| Current input | ≈ 100 mA |
| AS 100 Optical Sensor | |
| Bandwidth | DC ... 500 kHz |
| Measuring range | 0 V ... 50 V / 0 V ... 10 V DC (switchable) |
| Input resistance | 100 k? |
| Radiated immunity | > 100 V/m |
| Supply voltage | 3 V ... 16 V |
| Current input | ≈ 30 mA |
| Optical fibre length | 1 m ... 20 m |
Usage
Measurement under interference conditions
Measurement of analogue electrical signals under extreme electromagnetic stress such as:
- Coupling of radiated or conducted RF emissions
- Fast transients burst/ESD
- High potential (high voltage)
EMC tests as the main field of application:
- Radiated RF emissions EN 61000-4-3: 80 MHz - 1 GHz, 80% AM (1 kHz), anechoic chambers TEM cells stripline,
- Conducted RF emissions EN 61000-4-6: 40 Veff, 150 kHz - 230 MHz, 80% AM (1 kHz)
- Burst EN 61000-4-4
- ESD EN 61000-4-2
Measured signals:
- Supply voltages (switching controllers, linear controllers),
- Reference voltages,
- Digital signals (optical couplers, optical receivers),
- Analogue signals (operational amplifiers, ADC, DAC).
Specific measurement technology:
To measure analogue signals under extreme interference conditions, measurement technology is needed that
- itself is not affected by disturbance fields and thus does not simulate any disturbance in the equipment under test (EUT).
- can be connected to the EUT in a decoupled way, i.e. connecting the probe head does not result in the development of additional disturbance current paths through which disturbances can penetrate or be discharged.
The A100 / A200 / A300 optical fibre measurement systems meet these demands.
Specific measuring task
Analogue electronic modules are generally influenced in EMC tests when RF, modulated by 1 kHz, is applied to the EUT. This influence is due to the fact that the infiltrated RF disturbance is demodulated at PN junctions of the electronic circuit. This generates signal level fluctuations or 1 kHz disturbance signals. The 1 kHz disturbance signal is produced through modulation of the RF disturbance by 1 kHz.
Relatively slow disturbance signals with a fundamental wave of 1 kHz, which mostly interfere with analogue circuits, are charac-teristic for RF disturbance coupling.
Figures 1 to 6, on the next page, show examples of useful signals that were subjected to disturbances. The deviation of the signal form from the sine wave varies, i.e. the disturbance signal also contains a harmonic component as well as the fundamental one. The task is to correctly measure these relatively slow disturbance signals under extreme RF interference conditions.
The A100 set / A200 set / A300 set measurement systems are ideal for these conditions because of their high disturbance immunity.
Examples of disturbed useful signals
Signals were measured with the AS 100 optical fibre probe.
Radiated RF emissions: 250 MHz, 80 % amplitude-modulated by 1 kHz
EUT: operational amplifier circuit; RF coupling via an operational amplifier input; the disturbance signal was measured on the output.
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| Figure 1 The oscillogram shows a constant useful signal with a demodulated 1 kHz component. | Figure 2 The demodulated 1 kHz disturbance signal, superimposed on the useful signal, shows a large harmonic component. |
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| Figure 3 The demodulated 1 kHz disturbance signal is limited by the lower rail. | Figure 4 Useful signal without interference |
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| Figure 5 Useful signal with 1 kHz disturbance signal | Figure 6 Useful signal with 1 kHz disturbance signal limited by the upper rail |
Safety instructions
When using a product from Langer EMV-Technik GmbH, please observe the following safety instructions to protect yourself from electric shock or the risk of injuries.
Read and follow the instructions in the user manual and keep it in a safe place for later reference. The device may only be used by personnel who are qualified in the field of EMC and who are fit to work with and possibly be influenced by disturbance voltages and (electric and magnetic) burst fields.
- Read the operating and safety instructions for all devices used in the set-up.
- Never use any damaged or defective devices.
- Only connect and disconnect an AS XXX sensor when it is not subjected to any interference.
- Carry out a visual check before using a measurement set-up with a Langer EMV-Technik GmbH product. Replace any damaged connecting cables before using the product.
- Never leave a product from Langer EMV-Technik GmbH unattended whilst it is in operation.
- The Langer EMV-Technik GmbH product may only be used for its intended purpose. Any other use is forbidden.
- People with a pacemaker are not allowed to work with this device.
- The test set-up should always be operated via a filtered power supply.
Attention! Functional near fields and interference emissions may occur when the probe is operated. The user is responsible for taking appropriate precautions to prevent any interference with the correct function of products outside the operational EMC environment (in particular through interference emissions).
This can be achieved by:
- observing an appropriate safety distance
- using of shielded or shielding rooms
The disturbances that are injected into the modules can destroy the device under test (latch-up) if their intensity is too high. Protect the device under test by:
- increasing the disturbance gradually and stopping when a functional fault occurs
- interrupting the power supply to the device under test in the event of a latch-up.
Attention! Make sure that internal functional faults are visible from outside. The device under test may be destroyed due to an increase in the injection intensity if the faults are not visible from outside.
Take the following precautions if necessary:
- monitor the representative signals in the device under test
- use a special test software
- monitor visible reaction of the device under test to inputs (reaction test of the device under test).
We cannot assume any liability for the destruction of devices under test!
Warranty
Langer EMV-Technik GmbH will remedy any fault due to defective material or defective manufacture, either by repair or by delivery of spare parts, during the statutory warranty period.
This warranty is only granted on condition that:
- the information and instructions in the user manual have been followed.
The warranty will be forfeited if:
- an unauthorized repair is performed on the product,
- the product is modified,
- the product is not used for its intended purpose.
