Sigma C4 manual Maximizing Ramp Speed & Other Ramp Considerations

Page 47

Program step.substep

Data

Effect/Purpose

05.0

78.0

Sets temp setpoint to 78°

05.1

00.20

Sets ramp time to 20 minutes

05.2

00.20

Sets hold time to 20 minutes

05.3

6

Sets step 6 as next step to execute

05.4

1

Selects probe 1 for active control

6.1.2 Maximizing Ramp Speed & Other Ramp Considerations

When a ramp time is specified in a program step, the controller attempts, within the limits of system capability, to achieve a linear temperature change rate such that the setpoint is achieved precisely at the end of the ramp period. If an insufficient ramp time is specified, some of the hold time will be “borrowed” to allow the ramp to setpoint to complete.

To achieve the maximum ramp rate, set the ramp time (substep 1) to 00.00 and the hold time (substep 2) to 99.00. A program step with a ramp time of 00.00 and a hold time (substep 2) of 99.00 will cause the controller to achieve the setpoint as quickly as possible then immediately execute the next step. If a specific hold time following ramping at maximum ramp rate is required, then use two steps. Both steps should specify the same setpoint. The first step should have a ramp time of

00.00and a hold time of 99.00. The second step should have a ramp time of 00.00 and the desired hold time.

Note & Warning: A program step with specified ramp and hold times will terminate at the end of the specified time (ramp time + hold time), regardless of whether the controller was able to achieve the setpoint. On the other hand, a maximum speed ramp step (substep 1 = 00.00 & substep 2 = 99.00) will not advance to the next step until and unless the setpoint is achieved. If the unit under test generates or absorbs heat in a manner that prevents the test environment from ever becoming stable at the setpoint, the program will “hang” on such a step as it will not advance to the next step unless it can stabilize the platform or chamber at the setpoint.

A program step with a ramp time of 00.00, a hold time of 00.00, and a probe number of either 1 or 2 is a null program step. A null program step has no effect on the temperature setpoint of the chamber. It is used to fill an unneeded step in an existing program.

C4 Manual Rev 7.5.2

47

Image 47
Contents Sigma Systems Programmable Temperature Controller / InterfaceC4 Manual Rev Table of Contents Intelligent 2 Probe Control C4 Manual Rev C4 Manual Rev C4 Manual Rev C4 Manual Rev Models C4 & CC-3.5Explained IntroductionGeneral Description Release 7.5.2 Firmware Custom Features / Interchangeability WarningC4 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 Front Panel Physical DescriptionMode Switch Clear Prog J1 TOP Rear Panel ConnectionsStartup Displays General Operation & Error ConditionsC3-5 Rel 200 100c 392 148fUpdating Firmware Upgrading Firmware by Prom Replacement Making the physical connection for upload Ee busy and then su done Restoring Setup Parameters to Default ValuesRs load Su resC4 Manual Rev Fahrenheit Operation P1fProbe Out of Range Shutdown System Operating Temperature RangeP1 lo P1 hi P1 err P1 -err All res Internal Error Shutdown ConditionsRes err Software Probe Correction Calibration Su errStatus 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 Displaying Temperature Local Mode Basic OperationDisplaying 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 00.2 Substep Step Data 00.000.1 Ramp timeMaximizing Ramp Speed & Other Ramp Considerations Displaying Program Steps not during execution Clearing Program Memory Reinitializing program stepsPress 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 System Information Queries Command Summary by functional groupSystem 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 IEEE-488 Gpib Error and Status Reporting OverviewTemperature 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 Temperature Control Terms PID Setup fields 0, 10, 11 Blower Shut-off Mode Setup fieldEntering probe correction setup data C4 Manual Rev C4 Manual Rev Programming Examples & Notes Appendix00.4 00.000.2 00.3Using shortcuts to shorten program entry time DISP/CNTLSTART/STOP 9900CLEAR/ENTRY 6 Enter 04.4 04.004.2 04.307.4 07.007.2 07.3C4 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 101 Field Calibration of Model C4 Controller102 103 TroubleshootingNoise Immunity 105 Firmware Upload Problems 107 Temperature Control PID Tuning & Problems108 109 110 111 Technical Support, Repairs & Returns U1f 102.7113 Index114 115 GpibIEEE488 Gpib 117 118 119 SRQ120