Sigma C4 manual 110

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There will always be some oscillation, but a proper setting of the integral term will keep these oscillations very minor and within the range of established control accuracy. When the C4 is shipped from the factory, the integral term is set such that it will work well for most applications. Small adjustments to the proportional term rarely require adjustment of the integral term. Change this setting in small amounts only after careful demonstration of the need.

The Differential Term

The Differential term (Setup field 11) is the least often changed term. It’s effects on the other terms are subtle and illusive to most users. Don’t change this term unless you are thoroughly convinced of the necessity for doing so. The differential term supplies an anticipatory response that can be helpful with slow processes (large loads). It helps to compensate for the effects of thermal inertia at it’s extremes. If the term is too small, anticipation may be inadequate for slow responding systems and the setpoint may be illusive. If the differential term is too large, the system may over anticipate and begin excessive oscillation. The differential term changes the period of any temperature oscillations. This can be helpful in the rare event that a change in the proportional or integral term has set up an oscillation that seems “hard to break”. If this term is excessive, the oscillations that develop are typically more rapid than those associated with an excessive integral term value. Note that this term has such profound effects on the other two that there is a strong possibility that if you change this value, you will have to adjust one or both of the other term values as well.

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C4 Manual Rev 7.5.2

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Contents Programmable Temperature Controller / Interface Sigma SystemsC4 Manual Rev Table of Contents Intelligent 2 Probe Control C4 Manual Rev C4 Manual Rev C4 Manual Rev C4 Manual Rev Introduction Models C4 & CC-3.5ExplainedGeneral Description Custom Features / Interchangeability Warning Release 7.5.2 FirmwareC4 vs. CC-3 Differences What’s New Firmware Uploads Forced Start from Prom Firmware Internal Error Shutdown Conditions Intelligent 2 Probe Control Probe Averaging Program Mode Step Insert & Delete RSA Remote Mode Setup Parameter Commands Physical Description Front PanelMode Switch Clear Prog Rear Panel Connections J1 TOP200 100c 392 148f General Operation & Error ConditionsC3-5 Rel Startup DisplaysUpdating Firmware Upgrading Firmware by Prom Replacement Making the physical connection for upload Su res Restoring Setup Parameters to Default ValuesRs load Ee busy and then su doneC4 Manual Rev P1f Fahrenheit OperationProbe Out of Range Shutdown System Operating Temperature RangeP1 lo P1 hi P1 err P1 -err All res Internal Error Shutdown ConditionsRes err Su err Software Probe Correction CalibrationStatus and Error Reporting Fail-safe System C4 Manual Rev Intelligent 2 Probe Control How Intelligent 2 Probe Control functions Preparing for Intelligent 2 Probe Control Using Intelligent 2 Probe Control Local Mode Basic Operation Displaying TemperatureDisplaying and Changing the Setpoint S1 102.6 s1fS1 nsp S1f nsp Controlling to a Setpoint Sor -sorSp err C4 Manual Rev Description of a Program Step Program Mode06.0 Ramp time Substep Step Data 00.000.1 00.2Maximizing Ramp Speed & Other Ramp Considerations Clearing Program Memory Reinitializing program steps Displaying Program Steps not during executionPress CLEAR/ENTRY Entering or Changing a Program StepInsert Program Step Running Executing a Program Delete Program stepPress CLEAR/ENTRY Press CLEAR/ENTRY again Program Run Time Information/Considerations 005 sor Sor 007 nop2Loop Special Commands External Compressor On Common Programming Issues C4 Manual Rev IEEE-488 Interface Remote ModeEIA-232 Interface Command Summary by functional group System Information QueriesSystem Information Queries For Celsius mode For parameters numbered 0 through C4 Manual Rev Operation Information Queries & Commands REerror byteCRLF C4 Manual Rev Qccrlf PTnCRLF Setup Parameter Commands SC1 0 2.3 100 WP 6 5 5CRLF Upcrlf System Operation Commands Celsius mode Will hold the current setpoint for 1 hour and 20 minutes U1c 65.0 u1f Error and Status Reporting Overview IEEE-488 GpibTemperature in 20 minutes C4 Manual Rev Error/Status String Bit Definitions C4 Manual Rev Setup Mode PID controller, Integral term Adjustment not Displaying the Field Values Auto-start Mode Setup field Changing the Value of a Setup FieldTwo Probe Mode Setup field Blower Shut-off Mode Setup field Temperature Control Terms PID Setup fields 0, 10, 11Entering probe correction setup data C4 Manual Rev C4 Manual Rev Appendix Programming Examples & Notes00.3 00.000.2 00.4Using shortcuts to shorten program entry time 9900 DISP/CNTLSTART/STOPCLEAR/ENTRY 6 Enter 04.3 04.004.2 04.407.3 07.007.2 07.4C4 Manual Rev Sigma Systems C4 Programming Worksheet Sample Command Structure for IEEE-488 Gpib Operation Disp A$ Installation and Use of TTL Outputs and Input Field Calibration of Model C4 Controller 101102 Troubleshooting 103Noise Immunity 105 Firmware Upload Problems Temperature Control PID Tuning & Problems 107108 109 110 111 U1f 102.7 Technical Support, Repairs & ReturnsIndex 113114 Gpib 115IEEE488 Gpib 117 118 SRQ 119120