Sigma C4 manual Noise Immunity

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train your users to use their finger to discharge the static potential they may have accumulated on something other than the C4 front panel.

9.7.4 Noise Immunity

Noise can show up as lost or incorrect data sent over the bus. In extreme cases this noise can disrupt controller operation regardless of whether computer bus is in control or not. The following modification has been found to solve many computer bus related noise problems. It will provide static ground to the backshell of the IEEE 488 bus connector as well as pin 1 of the EIA-232 connector, bypassing any path through the digital circuitry. It is not done at the factory because in some cases it actually degrades noise immunity by creating a ground loop.

Bus static ground connection is made as follows: Solder a short green 22g. wire to the A-Board static ground eyelet located below the IEEE-488 connector. Hook the other end of the wire to a horseshoe lug and connect it to the main terminal strip J1, lug #3. (green).

9.7.5 Diagnosing and Solving Local Mode Problems

Controller starts immediately in Local Mode

If the system improperly begins controlling to the setpoint when you turn the controller from OFF to LOCAL Mode, before you press <START/STOP>, the Autostart setup parameter (F14) is set to enable Autostart. Resetting this setup parameter to 0 will disable the automatic starting feature.

9.7.6 Diagnosing and Solving Program Mode Problems

Hard Loops

Also note that hard loops will execute forever. Standard loops, using the loop command, do not allow nesting. Only one loop may be active at a time. If you have a nested loop, it may appear to function properly, but it will probably never complete.

104	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 TOPGeneral Operation & Error Conditions C3-5 Rel200 100c 392 148f Startup DisplaysUpdating Firmware Upgrading Firmware by Prom Replacement Making the physical connection for upload Restoring Setup Parameters to Default Values Rs loadSu res 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 Substep Step Data 00.0 00.1Ramp time 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 & Notes00.0 00.200.3 00.4Using shortcuts to shorten program entry time 9900 DISP/CNTLSTART/STOPCLEAR/ENTRY 6 Enter 04.0 04.204.3 04.407.0 07.207.3 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