The performance quality of encoders begins with a customer-centric design and professional standardization of encoder design.

EMCLearning of electromagnetic compatibility experimental certification, including100Anti interference composite experiment of meter transmission cable

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Why does the encoder signal always jump on site? Why are there always so many interferences and troubles in automated sites? Why do automation field service engineers spend more than half of their time a year on site debugging, finding problems, repeatedly going to the site to solve problems, or just rushing to the site?

Among them, interference is really a headache. So what about the resistance of the encoder? There must always be a comparable standard.

In addition to repeatedly emphasizing the selection of encoder principles, the anti-interference of the value encoder based on the full stroke true value encoding principle is far superior to the encoder based on incremental value encoding (as well as those with battery memory and Wiegand memory containing electronic counters and false value encoding)EMCElectromagnetic compatibility and anti-interference are also key, and specialized measures should be taken from the design stageEMCDesign is also an important comparative evaluation basis for encoder performance. And thisEMCElectromagnetic compatibility must be verified by a third partyEMCLaboratory certified. For example, the "German Rhine" headquartered in GermanyTÜVThe laboratory. The comparison of the resistance of the encoder depends on the third-party certificationEMCTest certification certificate.

In addition, due to the introduction of equipment from the Eight Nation Alliance in China, the electrical environment of Japanese and European systems is often mixed. If combined with low-end and unprofessional configurations, the quality of on-site workers varies greatly, and the complexity of the site is much greater than that of German factory sites. Even if "German imported" encoders are used, on-site interference problems often occur, which requires on-site engineers to spend a lot of time solving the interference problems.

For example, grounding issues:

What is land?

..Electrical engineer: Ground is the reference voltage of the circuit

..Structural Engineer: The metal casing of the equipment is the ground

..Electrician: The ground is the earth, that is, the earth

Unfortunately, for encoders, the Japanese encoders introduced or learned in the domestic market are of economic grade, and electrical engineers tend to design them with a bias towardsNPN, that is, a common anode; The design of European encoders and motors tends to be biased towards electrical engineersPNPThat is, a common cathode. These two designs tend to be mixed together and appear to have an equipotential grounding design. However, in actual use, the local and instantaneous potentials are often not at the same equipotential. Therefore, even in European systemsEMCThe designed encoder may not necessarily be able to adapt to the complex interference of automation sites in China. These encoders are used in China and need to be equipped with long-distance signal cables and grounding methods to withstand potential interference environments on siteEMCLaboratory testing certification.

Taking advantage of our encoder at the frontEMCThe validity period of the certification is about to expire and needs to be re certified. We haveGMX60The value of the multi turn encoder is sentTUV Rheinland (Shanghai)Laboratory certification and simulation of on-site applications in China, accompanied by100The signal cable and signal receiving instrument of the meter are tested and certified again under electromagnetic interference environment.

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Standard organizationEMCElectromagnetic compatibility testing certification is a standard for evaluating the resistance of encoders. Imported encoders from the pastEMCThe test report is based solely on the testing of the encoder under foreign laboratory conditions. And this time we're sendingTUVThe testing is based on the complexity of the Chinese site, where there are often long encoder cables. However, in the complex electrical environment of the site, this cable is also highly susceptible to interference, which can affect the encoder signal reception of subsequent equipment. Or there may be interference introduced into the encoder through this long-distance signal cable. So our encoder this timeEMCElectromagnetic compatibility anti-interference testing has put forward higher requirements, which is to simulate on-site encoder signals with100At the same time, when the cable is in an interference environment, the test signal is100Can the reception after the cable withstand the interference environment and comply with the requirementsEMCThe test passed under certain conditions.

EMCImportant Basic Standard Series（IEC61000Series)

Standard Number Name

IEC61000-4-1Overview of Immunity Test

IEC61000-4-2Electrostatic discharge immunity test

IEC61000-4-3Radiated (Radio Frequency) Electromagnetic Field Immunity Test

IEC61000-4-4Electric fast transient/Pulse group immunity test

IEC61000-4-5Surge (impact) immunity test

IEC61000-4-6Immunity Test for Conducted Disturbances Induced by Radio Frequency Fields

IEC61000-4-8Power frequency magnetic field immunity test

IEC61000-4-11Voltage sag, short-term interruption, and voltage variation immunity test

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Electrostatic discharge immunity test

according toEMCElectromagnetic compatibility standards

..Experimental purpose: To simulate the discharge of operators or objects in contact with the equipment and the discharge of people or objects to adjacent objects, in order to investigate the resistance of the tested equipment to electrostatic discharge forces. The former is directly coupled through a conductor and belongs to direct discharge. The latter is through spatial radiation coupling and belongs to indirect radiation effects.

Automated site: corresponding to the electrostatic discharge associated with a large amount of dust particles on site.

Radio frequency electromagnetic field radiation immunity test

..Implementation of the experiment

..use1kHzThe sine wave is used to process signals80%After amplitude modulation, in80～1000MHzPerform sweep frequency measurement within the frequency range, with a scan step size of the previous frequency1%This part is implemented through computer and software control.

..The scanning dwell time at each frequency point should not be shorter than the time required for the operation and response of the tested equipment, generally set to one second. If there are special requirements for the product, the dwell time can be extended.

..The test equipment should be tested under the horizontal and vertical polarization of the transmitting antenna.

Automated site: Corresponding to the electromagnetic wave emission interference of various metals in different frequency bands, including metal wire ends and sharp angle electromagnetic wave emission interference.

Electrical Fast Transient Pulse Swarm Immunity Test

according toEMCElectromagnetic compatibility standards

..Objective of the test

Evaluate the performance of power supply ports, signal and control ports of communication and electronic devices under repeated fast transient pulse group interference,Verify communication and electronic devices for transient processes from operations(Such as breaking inductive loads, relay contact bouncing, etc)Immunity to various types of transient disturbances in.

Automated site: Corresponding to the interference from direct contact conduction and induction caused by the encoder housing and long-distance cables.

Lightning surge immunity test

according toEMCElectromagnetic compatibility standards

..Objective of the test

Evaluate the performance of the tested equipment against high-energy interference on power lines and interconnection lines. This experiment is generally used to simulate indirect lightning strikes encountered by the tested equipment in different environments, or voltage and current surges caused by switch switching processes.

Select the coupling network corresponding to the port of the subject. The power port, unshielded communication line port, and unshielded interconnection line port all have corresponding different coupling networks.

..At least positive and negative interference should be added to each selected location5Next time, every interval1min.

..Surge impact must be applied to both line to line and line to ground. When conducting line to ground tests, unless otherwise specified, the test voltage must be sequentially applied between each line and ground

Automated site: Induced surges caused by instantaneous power start-up, electromagnetic valve coil action, high-power motor start-up, high-power contactor switch action, and so on.

Outdoor use site: Lightning strikes in the distance are induced instantly by the earth, and ordinary grounding cannot quickly equalize the potential at this time.

Immunity to Conducted Disturbances Induced by Radio Frequency Fields

according toEMCElectromagnetic compatibility standards

..Objective of the test

Evaluate the performance of power supply ports, signal and control ports of communication and electronic devices when disturbed by conducted interference signals induced by radio frequency electromagnetic fields.

..During the experimental process,EUTPlaced above the ground reference plane0.1mOn the insulation bracket, cope withEUTTest every port of..use1kHzThe sine wave is used to process signals80%After amplitude modulation, in0.15～80MHzPerform sweep frequency measurement within the frequency range, with a scan step size of the previous frequency1%This part is implemented through computer and software control.

..The scanning dwell time at each frequency point should not be shorter than the time required for the operation and response of the tested equipment, generally set to one second. If there are special requirements for the product, the dwell time can be extended.

Automated site: Corresponding to possible external electromagnetic wave interference from other equipment on site.

Voltage sag, short interruption, and voltage variation immunity test

according toEMCElectromagnetic compatibility standards

..Objective of the test

Simulate the power grid caused by faults in the power supply grid or substation equipment, sudden large changes in load, or continuous changes in load

Voltage instantaneous drop and short-term interruption,Test the immunity of the tested equipment to the above situation.

EUTThe test level and duration are selected according to the requirements of the standard or product technical conditions, and after combination, arranged in the order of delivery and tested sequentially. The number of tests for each combination state is specified as3The interval between the second experiment is seconds10second

The sudden change in power supply voltage during the experiment occurs at the zero crossing point of the voltage and at the critical phase specified in the product technical conditions. For three-phase power supply equipment, tests are generally conducted phase by phase.

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The final test results are satisfactory. After simulating the actual electrical environment of automation sites in China, we added100After testing the encoder and receiving the signal from the terminal of the equipment, the encoder sent for experimental certification also passed the German Rheinland test in one goTUVlaboratoryEMCTest certification. Proved the professionalism of EMC design for GEMPLE encoder.

A good encoder requires professional, serious, and persistent perseverance and patience to ensure qualityGEMPLE