Emerson Process Management 9110-00A, Series 9110, CI-9110 Guidelines for System Grounding

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Supplement S1400

Guidelines for

System Grounding

- Contents -

IMPORTANCE OF GOOD GROUNDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

GENERAL RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

TRANSIENTS AND INTERFERENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

TYPES OF EARTH GROUNDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

SOIL CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

GROUNDING TECHNIQUES FOR 33XX SYSTEMS . . . . . . . . . . . . . . . . . . . 9 Several DPCs in Metal Cabinet w/ Power Supply . . . . . . . . . . . . . . . . . . . 10 Multiple DPC Cabinets w/ Local Supply in Each Cabinet . . . . . . . . . . . . 10 Multiple DPC Cabinets Powered by Single Supply . . . . . . . . . . . . . . . . . . 12 Multiple Clusters of DPC Cabinets Powered by Local Supplies . . . . . . . 14

IMPORTANCE OF GOOD GROUNDS

The equipment used with instrument systems must operate continuously within their stated accuracy over long periods of time with minimum attention. Since many system sites are unmanned and located in remote areas, failures resulting from an improperly grounded system can become costly in terms of lost time. A properly grounded system will help to: prevent electrical shock hazards resulting from contact with live metal surfaces; protect equipment from lightning strikes and power surges; minimize the effects of electrical noise and power transients; and reduce signal errors caused by ground wiring loops. Conversely, an improperly grounded system may exhibit a host of problems that appear to have no relationship to grounding. It is essential that the reader have a good understanding of this subject to prevent needless troubleshooting procedures.

Warning

This device must be installed in accordance with the National Electrical Code (NEC) ANSI/NFPA-70. Installation in hazardous locations must also comply with Article 500 of the code.

Supplement S1400 / 1

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Contents Remote Set Regulator Model 9110-00A IMPORTANT! Read Instructions Before Starting Warranty Phone MailBristol Inc Bristol Inc. Repair Authorization Form off-line completion Training 860 860 945-2213 FAX Telephone Support Technical QuestionsVisit our Site on the World Wide Web Training Courses Model 9110-00A Remote SET Regulator Supplemental Instructions Analog Regulator Model Product DescriptionTheory of Operation Remote Set Regulator Block Diagram of Analog Type Regulator Current Output Guard InputBlock Diagram of Raise/Lower Type Regulator Model Number Breakdown Data PlateRaise/Lower Regulator Model = Pneumatic Output = Mounting Arrangement Page In-Line Mounting GeneralMounting Two-Inch Pipe MountingGeneral Piping Pressure ConnectionsMoisture in Lines Regulator AssemblyBody and Cover Internal AccessLine Size VentingElectrical Conduit Port Safety NotePage Slide Switches with on Designation Using Option SwitchesCradle Switches with Open Designation RAISE/LOWER Input Models Switch FunctionsRegulator Assembly Switch SW1 & SW2 Functions & Settings Analog Input ModelsIncremental Signal Continuous SignalInput Filter Switch SW1 1-5, Pulse IncrementsGuard Logic Guard InputOutput Rate of Change Static or Dynamic Guard InputAnalog Failure Modes Fail Hold & Fail Zero Switch SW2 2-5, Output Rate Of ChangeFAIL-ZERO Mode Page Field Wiring Terminal Identification For Raise/Lower Models Terminal Identification For Analog Input ModelsAnalog Voltage Input with Guard RAISE/LOWER Inputs with Guard Analog Current Input 4-20 mA with GuardRaise/Lower & Guard Inputs from Relay Contacts Current Output to FSK Bi-State Transmitter DC PowerInitial Checks Operating NotesField Wiring CI-9110 Service Troubleshooting Hints General Principles Setting Output LimitsTest Setup ProcedureCalibration Precaution Calibration Test SetupPreliminary Calibration Check Analog Test SetupPressure Output Check Detailed Calibration for Analog ModelFeedback Zero & Span Current Output Span & LoadDetailed Calibration for RAISE/LOWER Model Raise/Lower Test SetupCPU Board & Termination Board Reference Table PCB Reference DrawingsAssembly, Analog Type CPU Board with Current Output Assembly, Raise/Lower Type CPU Board with Current Output RAISE/LOWER Input Model Analog Input ModelStepper Drive Mechanism Analog OutputAccuracy Analog Models Accuracy RAISE/LOWER ModelsRange Factory Calibrated with Pressure Regulator AssemblyInstrument Enclosure EnvironmentalHumidity 10 to 95% over -20to +130 F -29to +55 Range Parts Referenced in Figure Model 9110 Main PartsRemote Set Regulator Actuator Unit Remote Set Regulator Actuator Unit Mounting Parts Remote SET Regulator Basic Parts Remote Set Regulator Assembly Basic PartsGuidelines for System Grounding Basic Ground Rod Installation General Recommendations Noise and Signal ErrorsGrounding of Equipment Housing Transients and Interference Grounding of Transmitter Types of Earth Grounds AC Power Grounding System Rocky Soil Dry SoilSandy Soil Following installation procedures apply Several DPCs Mounted in Metal Cabinet with Power SupplyGrounding for DPCs and Power Supplies Single Metal Cabinet Multiple DPC Cabinets Powered by Single Power Supply Elements of a Facility Ground System References Multiple Clusters of DPC Cabinets Powered by Local SuppliesPage Remote Set Regulator Model 9110-00A