Industral Bus, Field Bus health test with scm125 b
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This document covers industrial network troubleshooting, focusing on methodologies, tools, and key standards governing Ethernet and fieldbus mediums. It includes techniques for diagnosing connectivity issues, verifying signal integrity, and maintaining network performance, with specific measurements and tools recommended for each layer of the network. The guidance aims to ensure efficient operation and minimize disruptions within industrial network systems.
Industral Bus, Field Bus health test with scm125 b
- 1. Industrial Network Troubleshooting Learn about the basic theory of today's industrial network systems. The standards that govern their operation and performance. The troubleshooting techniques and tools to keep them running. Industrial Network Basics Fluke Company Confidential 1
- 2. Network Maintenance & Troubleshooting • Where, what & how do I test an industrial network? Industrial Network Basics Fluke Company Confidential 2 Ethernet Protocol OSI Standards layers 1-5 (minimally) Measurements: •Switch port configuration •Traffic statistics •Transmission Alarms/errors •Packet routing, addressing & visibility •Latency & Throughput Ethernet Medium CAT 5E or fiber Measurements: •Length, Opens/Shorts •Wiremap •Impedance •Attenuation (Fiber) •Cross Talk •Certification to 10/100Mbit CAT standards FieldBus Medium Twisted pair/ standard AWG Measurements: •Connectors Opens/Shorts •Cable Length, Opens/Shorts •Impedance •Capacitance •Terminating Resistors •Ground connections FieldBus Signaling Single or differential voltage mode, plus device power Measurements: •Amplitude, Pos, Neg & differential levels •Bias and offsets •Device supply level •Noise & Distortion •Signal disturbances •Overall quality Servers Switches Controllers Physical medium Field DevicesJunctions/ Splices Connectors & Cables High Speed Network Backbone Copper, fiber or wireless Ethernet TCP/IP with managed switches Industrial Fieldbus IEC 61158, EIA 485 or ISO 11898 & other proprietary derivatives, industrial network protocols
- 3. Network Diagnostics Industrial Network Basics Fluke Company Confidential 3 Network Layer Problem Recommended Test Tool Cause Effect Ethernet Protocol Ethernet Comms Disruption •What, who is on the network? •Protocol alarm & errors •Bandwidth “hogs” Process Interruptions Protocol Analyzer EtherScope II One Touch Ethernet Medium Deteriorating connectivity •Cabling installation errors •Cable performance issues Segments go down, all data communication lost Cable installation Certification DTX-1800 Cable Verification Cable IQ FieldBus Medium Deteriorating connectivity •Cable opens/shorts •Open/shorted connectors •Too few/many terminations Cable & Connector Check 87-IV or 289 Precision DMM with low ohms & capacitance FieldBus Signaling Degraded signal integrity •Attenuation •Distortion •Disturbances Random shutdowns or device resets Oscilloscope Bus Health Analysis 125B Portable Oscilloscope with bus health test
- 4. Industrial Network Basics Fluke Company Confidential 4 1. Check network protocol errors – Network visibility or traffic utilization – Packet transmission errors (CRC, Framing, Checksum) – Protocol statistics 2. Verify Integrity of signaling – Signal compliance to vendor or industry standards • DC power levels, Attenuation, Distortion, Jitter or time errors – Signal disturbances or anomalies • Transients, Noise, Static Discharges 3. Measure state of cabling infrastructure – UTP or AWG cable impedance, terminations, opens or shorts – Cable performance (UTP) 10Mb, 100Mb, NEXT, mismatch pairs etc Diagnostics How To? NetworkPerformanceIssues? SegmentisDown? Is it the network communications, signaling or cable?
- 5. FieldBus Signaling • With an active network, start at one end of the network trunk. • Use an oscilloscope to capture the active encoded waveforms at each node • Deploy best practices – Capture and document the known good measurements at installation – Capture and document the same waveforms or measurement before and after any network add/change or repair. Industrial Network Basics Fluke Company Confidential 5 D/R D/R D/R D/R
- 6. Capture the encoded waveform • ScopeMeter 125B inputs perform differential measurements • First, analyze encoded digital signal in scope mode, check –Overall Quality –Noise –Offsets –Common Mode signals Industrial Network Basics Fluke Company Confidential 6
- 7. Waveform examples Industrial Network Basics Fluke Company Confidential 7
- 8. Check FieldBus Signaling Compliance • Fluke Bus Health mode, – Select from multiple bus standards – Measure network waveform critical parameters at each node – Use the eye diagram to visually inspect the integrity of the signals • Look for out-of-tolerances – Amplitude Levels – Time parameters – Noise or distortion • Check for signal disturbances such as – Transients – Static discharge – Erratic waveform fluctuations Industrial Network Basics Fluke Company Confidential 8 D/R D/R D/R D/R
- 9. Bus Health: Quantitative Test Results • Bus Health at a Glance, captures signal then, – Measures critical parameters, identified within the standard – Compares results to industry standard – Provide quick Go/No Go result Industrial Network Basics Fluke Company Confidential 9 Amplitude related measurements Time domain related measurements Noise or Distortion measurements Go/No Go Test result indicator Min Max Measurements over since activated
- 10. Bus Health: Qualitative Test Results Industrial Network Basics Fluke Company Confidential 10 • Bus Health eye pattern mode – Captures successive waveforms – Overlays these on top of each other – Provides a historic view of waveform changes – Identify extent of • Noise/Distortion • Disturbances Trigger synchronizing successive waveform captures Center ‘eye’, the clearer the eye the less distortion or jitter
- 11. Tools to maintain plant uptime! Test tools to keep your world up and running Industrial Network Basics Fluke Company Confidential 11 WAN Gateway Copper/Fiber Optic Network WiredEthernet Back Office/Operations Production Process 2 Production Process 1 HMI Boilers Chillers Storage Pumps Mixers Conveyors Automate d Packagin g Managed Switches Application Servers Physical Layer Signal Integrity verification Cable & plant equipment checks Process Loop Test & Calibration