Emerson Process Management CI-9110, Series 9110 General Recommendations, Noise and Signal Errors

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GENERAL RECOMMENDATIONS

When wiring equipment into a system, the electrical conduit must have a diameter that will accommodate the desired number of wires. The cross- sectional area of the conduit should be large enough to allow the wires to be pulled through without excessive tightness or binding. A conduit that is too tight can shred insulation, damage wiring, and result in possible opens, shorts, or intermittent effects. Such conditions are often difficult to trace because the defect is concealed inside the conduit.

Noise and Signal Errors

Noise and signal errors are often the result of poor wiring and grounding practices. Some common problem areas are listed as follows:

oShielding AIs and AOs. Very often analog DC signal leads must run parallel to wires radiating AC fields, pulse information, or switching transients. Due to inductive and capacitive pickup, some of this information can leak into an analog I/O and cause peculiar effects in the control systems. To minimize or eliminate this problem, the use of insulated and shielded, twisted lead pairs is recommended between the external devices (transmitters, sensors, etc.) and the instrument inputs (controllers, recorders, etc.).

The shields of each analog signal source should only be grounded at the input of the in- strument. In some equipment, the shield will connect to the instrument chassis. In other equipment, a "shield" terminal will be provided with several grounding options. The user should refer to the instrument manual and follow grounding recom-mendations.

oCommon Returns. The use of a single "common" return wire for two or more input signals is not recommended. This approach may introduce system ground loops that cause erroneous readings at the instrument. Shielded transmitter or sensor wires should be grounded at the input of the instrument, or connected to a shield terminal (where provided) to prevent "sneak" ground paths.

oDiscrete Outputs. Instruments provided with bi-state discrete outputs perform functions such as control switching, alarm switching or pulse duration com-munications. These outputs are furnished as either open collector or relay contact outputs that operate at low power levels. While these levels are sufficient to operate many devices, some will require much higher power levels. The use of external amplifiers or repeating relays to drive end devices will prevent output overload and add to the reliability of the system.

oCompatible System Wiring. In a distributed system, the designer should use the same wiring identification and color codes throughout to maintain system uniformity. By observing compatibility at all levels, wiring mistakes are minimized and troubleshooting tasks are simplified.

oPlacement of Wiring. The dressing or physical placement of wiring requires close scrutiny. Cables inside cabinets should be neatly secured at regular intervals. Cables running between cabinets at different locations should be placed in conduits. The cable length should allow sufficient slack for routine operational checks and maintenance of

Supplement S1400 / 3

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Contents Remote Set Regulator Model 9110-00A IMPORTANT! Read Instructions Before Starting Warranty Bristol Inc MailPhone 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 Theory of Operation Product DescriptionAnalog Regulator Model Remote Set Regulator Block Diagram of Analog Type Regulator Current Output Guard InputBlock Diagram of Raise/Lower Type Regulator Raise/Lower Regulator Model Data PlateModel Number Breakdown = Pneumatic Output = Mounting Arrangement Page Mounting GeneralTwo-Inch Pipe Mounting In-Line MountingGeneral Piping Pressure ConnectionsMoisture in Lines Regulator AssemblyLine Size Internal AccessVenting Body and CoverElectrical Conduit Port Safety NotePage Cradle Switches with Open Designation Using Option SwitchesSlide Switches with on Designation Regulator Assembly Switch SW1 & SW2 Functions & Settings Switch FunctionsAnalog Input Models RAISE/LOWER Input ModelsIncremental Signal Continuous SignalInput Filter Switch SW1 1-5, Pulse IncrementsOutput Rate of Change Guard InputStatic or Dynamic Guard Input Guard LogicAnalog 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 Test Setup Setting Output LimitsProcedure General PrinciplesCalibration Precaution Calibration Test SetupPreliminary Calibration Check Analog Test SetupFeedback Zero & Span Detailed Calibration for Analog ModelCurrent Output Span & Load Pressure Output CheckDetailed 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 ModelAccuracy Analog Models Analog OutputAccuracy RAISE/LOWER Models Stepper Drive MechanismInstrument Enclosure Pressure Regulator AssemblyEnvironmental Range Factory Calibrated withHumidity 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 Sandy Soil Dry SoilRocky 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
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