SIGMA SYSTEMS MODELS C4 & CC-3.5 PROGRAMMABLE TEMPERATURE CONTROLLER / INTERFACE OPERATING & PROGRAMMING MANUAL Firmware Version 7.5.2 Manual Revision 4 June 3, 1999 SIGMA SYSTEMS CORPORATION 1817 John Towers San Diego, California 92116 USA TEL: (619) 258-3700 WWW.SigmaSystems.Com C4 Manual Rev 7.5.
Copyright 1997, 1998 Sigma Systems Corporation 1817 John Towers El Cajon, California 92020 USA All rights reserved The manual may be reproduced, in whole, or in part, solely for the purposes of use and training for the use, of Sigma Systems equipment, or as required to assist in the sale of new Sigma Systems equipment. No modification of the content is permitted. C4 Manual Rev 7.5.
TABLE OF CONTENTS 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.1 Models C4 & CC-3.5 Explained . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.2 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.3 Custom Features / Interchangeability WARNING . . . . . . . . . . . . . . . . . . 11 1.4 Release 7.5.2 Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Updating Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.1 Upgrading Firmware by PROM Replacement . . . . . . . . . . . . . . 3.2.2 Upgrading Firmware by Uploading through C4 Serial Port . . . . Making the physical connection for upload . . . . . . . . . . . . . . . . Running the upload software on the PC . . . . . . . . . . . . . . . . . . Starting the upload on the C4 . . . . . . . . . . . . . . . . . . . . . . . . . . 3.
Invalid Loop Count Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Setpoint Out of Range Error . . . . . . . . . . . . . . . . . . . . . . . . . . 6.8 Special Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.8.1 Controlled Program Looping . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.8.2 External Compressor On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.8.3 External Compressor Off . . . . . . . . . . . . . . . . . . . . . .
7.7.8 TO & TF Turn Aux/Power Control Port On . . . . . . . . . . . . . . . . 7.7.9 QU Quit Controlling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8 Error and Status Reporting - Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8.1 Status Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8.2 Error Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.8.3 Error/Status String . . . . . . . . . . . . .
9.8 Temperature Control (PID) Tuning & Problems . . . . . . . . . . . . . . . . . . Adjusting for changing needs . . . . . . . . . . . . . . . . . . . . . . . . . The Proportional Term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The Integral Term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The Differential Term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.9 Displayed Messages and Errors Table . . . . . . . . . . . . . . . . . . . . . . . . . 9.
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1. INTRODUCTION This manual describes the operating procedures for the Sigma Systems Models C4 & CC-3.5 Controllers, microprocessor based controllers and control communications interfaces for the family of Sigma Systems temperature chambers and thermal platforms. 1.1 Models C4 & CC-3.5 Explained The models C4 & CC-3.5 controllers are successors to the model CC-3.
1.2 General Description Using the model C4, temperature control is available manually from the front panel, by use of user entered programs, or via remote control via either a EIA-232 or IEEE-488 GPIB. The controller has a precision temperature reading capability with a digital read-out. Two temperature probes can be connected to the controller allowing either probe or both probes to be the control probe(s) while either probe can be used to take measurements.
1.3 Custom Features / Interchangeability WARNING Each Sigma Systems C4 Controller has been custom configured for the chamber or platform with which it was supplied or for which it was specified. Many units include special wiring for custom control applications, precision fail-safe additions, non-standard voltages, external unit power control, etc. Units that may appear to be identical may be internally quite different.
1.5 C4 vs. CC-3 Differences (What’s New) 1.5.1 Hardware & Stability Improvements The new C4 introduces a number of new improvements to make the controller faster and more reliable than its predecessor. The C4 has a completely new digital processing board. The new board has a much faster processor, more memory, and a much faster IEEE-488 GPIB controller. Interrupts have been completely restructured to improve stability. The multilayer design is far more tolerant of both static and power line interference.
1.5.3 Firmware Uploads When new firmware is available for your C4, you can easily upload it into the controller using the controller’s serial port. The procedure requires only a diskette bootable PC and a serial cable and takes only about ten minutes. Firmware updates, when available, may be obtained on diskette for a fee from Sigma Systems or for free by download from www.SigmaSystems.Com or ftp.SigmaSystems.Com. See Section 3.2.2 1.5.
1.5.7 Internal Error Shutdown Conditions The C4 monitors system health by keeping track of three additional areas; they are: Processor health Memory condition Setup parameter table Tracked by watchdog timer Checked at startup Checked continuously as used Some detected internal errors can be repaired on the fly. If this is possible, the C4 will recover from the error and you will not know the error existed.
However, when the change in the Setpoint is very small, this “start from the beginning” search routine can search over such a wide range that it will introduce a “bump” in the platform or chamber temperature that can exceed the amount of the Setpoint change. The C4 includes an intelligent PID routine that constrains the search appropriately for the change in Setpoint and thus eliminates the “PID bump”. 1.5.11 Intelligent 2 Probe Control (Probe Averaging) (Not in this release.
1.5.13 Program Mode Step Insert & Delete Program steps may now be deleted from or inserted into programs. See Sections 6.5 & 6.6. 1.5.14 Program Mode Any Step Points to Step 100 Any program step may now point to step 100 (program end) as the next step to execute. 1.5.15 Program Mode Safer Program Clear Some deliberate delays have added to the key sequence to completely clear the program memory to lessen the likelihood that all of program memory will be erased by accident. 1.5.
1.5.18 Remote Mode EIA-232 Port Initialization The CC-3 required that to use the EIA-232 port, the port had to be initialized by switching the mode switch to SETUP before switching to REMOTE mode. The C4 eliminates this requirement. The EIA-232 port is initialized each time the remote switch is switched to REMOTE mode. 1.5.19 Remote Mode Fault Tolerant Parser The C4 uses a very fault tolerant parser.
1.5.22 Remote Mode Setup Parameter Commands SC WP BF BO SL SD UP Set Correction (Calibration) for Probe . . . . . . . . . . . Set PID Constants . . . . . . . . . . . . . . . . . . . . . . . . . . . Turn Blowers Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . Turn Blowers On . . . . . . . . . . . . . . . . . . . . . . . . . . . . Set UUT Temperature Limits . . . . . . . . . . . . . . . . . . Set UUT Temperature Differential Limits . . . . . . . . Write SRAM Parameters to EEPROM . . . . . . . .
2. PHYSICAL DESCRIPTION The SIGMA SYSTEMS Model C4 Controller fits into an area 3.5" x 5.5" x 9.5" long. Connection to the chamber or platform is made through an umbilical cable with a 12 pin connector that is standard for all SIGMA chambers and thermal platforms. Controllers destined for use with SIGMA thermal platforms have an additional 6 pin connector used for the sensor probe circuits.
COOL indicator lights when cooling is active, typically during the time the cryogenic valve is open on cryogenically cooled units. HEAT indicator is pulsed along with the on and off function of the heaters. These indicators are active in all modes of operation. RUN indicator shows whether the chamber temperature is being controlled. 2.1.3 Mode Switch The Mode Switch is used to apply power to the chamber and to select the mode of operation.
parameter F15. Likewise, at the end of a local or remotely controlled program, chamber blowers will continue to run, but heating and cooling will be disabled. Note that a chamber in this condition, with blowers running, will exhibit some heating due to blower air friction. This effect is exaggerated in units equipped with high velocity blowers. Moving the rotary switch between OFF and LOCAL will maintain the last used setpoint for the next operation of the controller. See 6.
2.2 Rear Panel Connections At the rear panel of the controller, a cable is provided to connect to the power, cooling solenoid, mechanical refrigeration and heaters of the chamber. In addition, a six lug screw terminal block (J1) is provided for eyelet terminal connection of the temperature probes and for connection of one additional optional device such as the Sigma PFS-2 Precision Fail Safe.
3. GENERAL OPERATION & ERROR CONDITIONS 3.1 Startup Displays 3.1.1 Model Number and Firmware Version Number Display The C4 identifies itself upon power up. It will display the model number for 1 second, then the firmware version number for 2½ seconds as follows: c3-5 rel 7.5.2 c4 rel 7.5.2 3.1.2 Temperature Range Display Each C4 controller is set at the factory for use with a specific device (chamber or platform).
3.1.3 Serial Number Display The controller serial number can be displayed at startup by pressing c3-5 or c4 ) is displayed. while the model number ( number will be displayed in the format: The serial 4-0 3276 3 4 The first digit (either a or ) indicates whether the controller is a CC-3.5 or C4, and the 5 digits to the right of the dash is the sequential part of the number. There is no significance to the leftmost of the 5 sequential digits being separated from the other 4 digits.
3.2.1 Upgrading Firmware by PROM Replacement Before starting, be certain that you have a properly grounded antistatic surface and a grounding strap to prevent damaging the C4 components during disassembly and reassembly. Remove the C4 from its cabinet or rack, then remove the EEPROM chip that contains the firmware and replace it with a new one containing the updated firmware. Firmware EEPROMs are available from Sigma Systems. There is a charge for firmware EEPROMs.
Use a DOS bootable diskette and a PC type computer to load the new firmware through the C4's serial port. You can obtain the required diskette from Sigma Systems for a fee, or you can provide your own DOS bootable diskette and obtain the necessary files for the upload process from the Sigma Systems site on the Internet. The Internet address for this site is: www.SigmaSystems.com The download file, SSUPxxxx.EXE, may contain specific instructions that replace the instructions in the next paragraph.
uploads so that you can upload to one controller while connecting and disconnecting the other. Starting the upload on the C4 When the PC is ready, turn the C4 controller on. During the 1 second display of the model number, rapidly press three times. The display will read: rs load The firmware upload should begin immediately. The PC will indicate when the load is complete. If you have difficulties, see the trouble shooting information in Section 9.7.8. 3.
When you have set the necessary parameters for your needs, you are ready to go to LOCAL, PROGRAM, or REMOTE mode. 28 C4 Manual Rev 7.5.
3.4 Fahrenheit Operation The C4 can use either Celsius or Fahrenheit temperature scales. Celsius is the default mode. When the controller is operating in Celsius mode it’s behavior is identical to the model CC-3 controller. When the controller is operating in Fahrenheit mode, both the displays and the bus communications are different.
3.5 System Operating (Temperature) Range The C4 controller operates within the limits of the system devices. There are 3 pairs (low-high) of temperature limits that constrain the range of operations. 1. The range of the C4 as it is set at the factory 2 The range of the controlled device (chamber or platform) as described by setup parameters F25 & F26. 3 The range of the UUT (unit under test) as described by setup parameters F27 & F28.
“LO” indicates that the reported temperature was 20-50/C below the System Operating Range. “HI” indicates that the reported temperature was 20-50/C above the System Operating Range. The number following the the probe that reported the excessive temperature.
The Probe Out of Range Shutdown condition can be cleared by pressing in Local or Program mode, by rotation the mode switch on the front panel to a different position, or by issuing a Device Clear in Remote mode. 3.
The mode switch must be subsequently turned to the SETUP position to clear the display and resume normal operations. Be sure you remember to restore any setup parameters that have been changed by the system reset. 3.7.3 Setup parameter integrity checking Each time the system must rely on a system setup parameter the condition of the setup parameter table is checked against a replica that the system stores in another place in memory.
U1 C1 U2 C2 2.3 0 99 100 The C4 will then calculate a new slope and offset for the entire probe curve. All temperatures reported by the corrected probe will be adjusted by applying this new slope and offset to the raw temperature data reported by the probe. Note: Software probe correction is done separately for each probe.
Some errors, especially those unique to the C4, are only defined in the Error/Status String. In the event of one of these errors, bit 1 of the Error Byte (this bit was not used by the CC-3) is set to indicate an extended error. The Status Byte and SRQ are thus set as well. The Error/Status String is a bit mapped 64 byte string (512 bits) that contains both “event triggered” and “status monitoring” information. A complete description of the Error/Status String and it’s behavior can be found in Section 7.8.3.
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4. INTELLIGENT 2 PROBE CONTROL (Probe Averaging) (Not in this release. Available in next release, without charge. Contact Sigma Systems to receive a revised firmware EEPROM.) Intelligent 2 Probe Control allows the internal temperature of the UUT (Unit Under Test) to be used in the temperature control algorithm.
4.1 How Intelligent 2 Probe Control functions Intelligent 2 Probe Control takes advantage of the fact that increasing the temperature differential between two objects increases the rate of heat transfer between them.
than cold, or visa versa. To properly protect your object you need to be able to constrain the air temperature in the chamber (and thus the surface temperature of the object) such that the difference between surface temperature and the core temperature does not exceed some difference the object can tolerate. It would be useful to be able to specify such a differential tolerance for both the high and low thermal limits of the object. 4.
air stream temperature, based upon this 60/ limit, would not be allowed to drop to -100/ until the UUT core temperature had reached -40/ The same rules hold true for the high end of the UUT range except that the high differential limit (F30) is applied at the high limit of the UUT range (F28). For UUT core temperatures between those limits, a proportional differential limit is calculated by the C4 based upon the limits specified at the extremes.
5. LOCAL MODE ( Basic Operation ) The C4 Local mode of operation provides simple control of the chamber or platform through the front panel controls. In this mode, a single setpoint is entered from the front panel and the controller will attempt to have the chamber or platform reach and hold that temperature. In local mode the compressor of mechanically refrigerated units can be turned on or off using the button on the front panel.
probe mode, n can be 1 or 2 as the temperature display toggles between probe 1 and probe 2 with each press of the Display Temperature key. If Intelligent 2 Probe Control is implemented (probe number set to 0), the display will rotate from probe 1 to probe 2 to probe 0 (average), then back to probe 1, etc. with each press of . The temperature is displayed to the nearest tenth of a degree C. although internal temperature values are kept at a much higher precision.
4. Enter a setpoint temperature using the numeric, decimal point and sign keys. Numbers may be entered with a maximum of 1 decimal place. Pressing the sign <+/-> key will toggle the value between positive and negative. Positive values will have no indication, negative values will show a minus (-) sign to the left of the temperature display. 5. Errors may be corrected by simply pressing and rekeying the entry prior to pressing . 6.
5.4 Compressor Control (mechanically refrigerated unit control only) The compressor of a system employing mechanical refrigeration can be manually toggled at any time during local mode controlling operation by pressing the button. The REFER LED on the front panel indicates the state of the refrigeration compressor control port.
6. PROGRAM MODE The Program Mode allows more complicated front panel control than the Local Mode. The Program Mode allows a temperature control program to be entered into the controller memory for subsequent execution as required. Up to 100 program steps may be entered. Multiple programs may be entered and executed as long as the total number of steps in all programs does not exceed 100. Programs are stored in non-volatile EEPROM memory. See Appendix 9.1 for Sample Programs. 6.
6.1.1 Format of a Program Step FORMAT OF A STEP substep step )))))), )))0, * ** * 00.0 00.1 00.2 00.3 00.4 where: step substep -----------data------------TTT.T HH.MM HH.MM NNN P - temp (setpoint) ramp time hold time next step control probe is the current program step number (00 - 99) is the current program substep (0-4) TTT.Tis the setpoint temperature displayed to the nearest .
Program step.substep 05.0 05.1 05.2 05.3 05.4 Data Effect/Purpose 78.0 00.20 00.20 6 1 Sets temp setpoint to 78° Sets ramp time to 20 minutes Sets hold time to 20 minutes Sets step 6 as next step to execute Selects probe 1 for active control 6.1.
6.2 Clearing Program Memory (Reinitializing program steps) When the controller is shipped from the factory, all program steps are initialized to their default values as shown below. To create a usable program for the controller to run, the user enters replacement values in those program steps to be used. All program steps are retained in memory even during power down of the controller.
6.4 Entering or Changing a Program Step There is no difference between entering a program step and modifying an existing one. To change any part of the program, first display the current step by pressing . If you wish to make changes to a step other than the current step, enter the 1 or 2 digits for the step number (0-99) and press again. Substep 0 of the desired step will now be displayed. For each substep displayed, you may change the current value or accept the current value.
6.6 Delete Program step 1. Enter the step number to be deleted and press 2. Press . 3. Press again. The display shows “ del nn”, where nn = step number to be deleted. 4, Press to delete the step and move all higher steps down one step. 6.7 Running (Executing) a Program To start program execution, the beginning program step of the program to be run must be displayed. Displaying a specific program step is covered in Section 6.3.
6.7.1 Program Run Time Information/Considerations When a program is running, the display shows the currently executing program step number on the left and the total amount of remaining run time for that step on the right. The time displayed is the sum of any remaining ramp time and/or hold time. The temperature may be displayed by pressing while the program is running. Pressing will restore the display of the current step number and the time left in the step.
No Probe 2 Error If a program step calls for control by probe 2 when setup parameter F1 = 1 (number of probes) the C4 will generate a No Probe 2 Error. Example 007 nop2 You must either remove the step that calls for probe 2 or enable probe 2 with setup parameter F1 (See Section 8) before the program will run. See Section 8.3.
6.8 Special Commands There are special commands that use the substep data within a step for different purposes than normal. These commands are (6.8.1) Creating controlled loops, and (6.8.2 - 6.8.5) External port controls. In each case only some of the substeps are used. To enhance program readability, we suggest that you set any unused substep values to zero. 6.8.1 Controlled Program Looping The program may be placed into a controlled loop by the use of the PROGRAM LOOP special command.
encountering the loop statement in step 7, then steps 1-6 will already have been executed once and then again 5 more times as a function of the loop, for a total of 6 times. 6.8.2 External Compressor On When the Probe (substep 4) is specified as 4, the program step turns the refrigeration compressor control port on. Substeps 0 - 2 are ignored. Upon power up, start and stop of program execution, and changing of the mode switch, this port will be off.
When the Probe (substep 4) is specified as 7, the program step turns the optional load control port off. Substeps 0 - 2 are ignored. Upon power up and changing the rotary switch this port will be on. At start and end of program execution, this port will be automatically set to off. 6.9 Common Programming Issues 6.9.1 Step Numbering Remember that the first step or substep is 0 instead of 1. 6.9.
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7. REMOTE MODE Remote mode provides for control of the C4 from a remote computer or terminal using either standard EIA-232 serial communication or Instrumentation Standard IEEE-488 (GPIB) communication. Selection of the type of interface is made from the setup mode, see Section 8. NOTE: The IEEE-488.2 requirement for lockout of front panel control during IEEE-488 control is not enabled in this controller. The front panel mode switch remains active during remote control.
7.
7.4 System Information Queries 7.4.1 QV Query Firmware Version This command returns the current internal firmware release number in ASCII text in the following format: QVnnn.nnn.nnn Where nnn is the number of each part of the release number, padded on the left with leading zeros if necessary. Example: QV 007.003.001 The syntax for the command is: QV 7.4.
7.4.3 QR Query Controller Temperature Range This command returns the controller temperature range in ASCII text in the following format: QRthhhh-lll where t = C or F hhh = high limit lll = low limit\ Example: For standard range controller in Celsius mode: QR C200-100 The syntax for the command is: QR 7.4.
7.4.5 QF, QFA Query Setup Parameter Value This command returns the current (SRAM) value of a setup parameter field. QF requests the data to be returned in binary form, QFA requests the data to be returned in ASCII text form. The syntax of the command is: QFnn (Query for binary) QFAnn (Query for ASCII text) Where nn is a one or two byte ASCII text decimal number of the setup parameter field to be returned.
these working values in SRAM have modified by Remote Mode setup commands (See Section 7.6) they will not be the same as the non volatile EEPROM copy unless an UP command was subsequently used to permanently store the SRAM values to EEPROM. Upon exiting Remote mode, including by power loss, the SRAM values are discarded. Each time Remote mode is entered a new copy of the EEPROM setup parameter values is read into SRAM as a working copy. 62 C4 Manual Rev 7.5.
7.5 Operation Information Queries & Commands 7.5.1 RS, RSA Request Status Byte These commands retrieve the status byte. See Section 7.8.1.
7.5.2 RE, REA Request Error Byte These commands retrieve the error byte. Note: The error byte and byte 00 of the Error/Status String are cleared each time this command is used. See Section 7.8.2.
Note: Byte 00 of this string is the same error byte that is available using RE and REA commands. Byte 01 of this string is the same EIA-232 status byte that is available using RE and REA commands in EIA-232 mode. The EIA-232 version of the status byte is used in the Error/Status String, Byte 01 even in IEEE488 mode. Byte 00 & the Error, Setpoint Reached, and Interval Complete bits of byte 01 (as well as bytes 02-31) and the Error Byte are cleared each time a QE or QEA command is issued.
7.5.4 QC Query Last Command This command returns the last non-null command string sent to the controller. The returned string is the string that was delivered to the controller after the internal parser did any “fixing”. It does not have to be a valid command. The string is ASCII text and is terminated with . Null strings are discarded by the parser. Example: Previous command sent: QC returns: Ra, -55 RA -55 2 11 2,11 The syntax for the command is: QC 7.5.
7.5.7 PT Read Temperature This command is used to read the specified probe temperature. The format of the command is: PTn where n is the number (0, 1 or 2) of the probe to be read. Probe 2 is only available if enabled by Setup Parameter F1 (See Section 8). Specifying probe 0 will return the average temperature of the two probes. The response is ASCII text with temperature as a one decimal place number. Negative temperatures are preceded by a minus sign.
7.6 Setup Parameter Commands The commands in this section allow a user to change the value of some of the setup parameters that are stored in SRAM and used by Remote mode. The SRAM copy of the setup parameters is created upon entry to Remote mode from the nonvolatile copy that is kept in EEPROM for use by Local and Program modes. The commands listed in this section change only the SRAM working copy of the setup parameters.
Note: Software probe correction is done separately for each probe. The following table shows the U1, C1, U2, C2 setup parameter assignments: U1 C1 U2 C2 Probe 1 F17 F18 F19 F20 Probe 2 F21 F22 F23 F24 The syntax for the SC command is ASCII text as follows: SCnU1C1U2C2 where n = number of probe to correct U1, C1, U2, and C2 are floating point numbers to one decimal place. Example: SC1 0 2.3 100 101.
where p = proportional term constant (integer) i = integral term constant (integer) d = differential term constant (integer) Example: WP 6 5 5 There is no response to this command from the controller except to set the appropriate bit in the Error Byte in the event that the command or parameters are incorrect. 7.6.3 BF & BO Blower Off & Blower On Commands The BF and BO commands affect the state of setup parameter F15, (Blower Shutoff Mode). See Section 8.5 for a detailed explanation.
7.6.4 SL Set UUT Temperature Limits The SL command sets the lower UUT limit (setup parameter F27) and the upper UUT limit (setup parameter F28). For a detailed explanation of the effect of these parameters, see Sections 3.5 and 4. The command sets the lower and upper temperature limits at the same time. The syntax of the command is: SL lll.l uuu.u where: lll.l is the lower limit (F27) uuu.u is the upper limit (F28) lll.l & uuu.u are one decimal place numbers Example: SL -75 130 7.6.
7.7 System Operation Commands 7.7.1 SI Select Immediate Mode This command selects the immediate mode of operation. In immediate mode, a command is executed immediately when it is received over the interface. If a previous command is executing, it is canceled. Query or status commands do not cancel outstanding commands. Command syntax is: SI 7.7.2 SP Select Program Mode This command selects the program mode of operation. In program mode, commands are executed in the order they are sent.
7.7.4 GT, GTF Go To Temperature This command instructs the controller to control to the setpoint specified in the command. Bit 4 (setpoint reached) of the Status Byte is set when the chamber or platform has stabilized within .1 degree of the setpoint for 15 seconds. The command syntax is: GT[-]ttt.t GTF[-]ttt.t Celsius mode Fahrenheit mode Example: GT 125 GTF 180 Celsius mode Fahrenheit mode 7.7.
7.7.6 DL Delay (Dwell Interval) The DL command causes the controller to dwell at the setpoint for a specified interval of time before executing the next command. The Interval Complete bit of the Status Byte is set when the chamber or platform has completed the requested delay interval.
7.7.9 QU Quit Controlling The QU command stops the C4 from controlling. All heating and cooling is turned off, the blowers are set to the mode determined by setup parameter F15 (Blower Shut-off Mode). The command syntax is: QU After a QU command, the display will show: u1c 65.0 u1f 102.6 (Celsius mode) (Fahrenheit mode) Note: The C4 can also be commanded to STOP controlling the temperature by issuing IEEE-488 standard I/O statements ABORTIO, Bus Clear, or Selected Device Clear. C4 Manual Rev 7.
7.8 Error and Status Reporting - Overview There are three sources for error and status information: The Status Byte CC-3 compatible The Error Byte CC-3 compatible The Error/Status String (64 bytes) CC-3.5 & C4 only 7.8.1 Status Byte The Status Byte is a one byte block of data in which each of the eight bits reports the status of an item.
Interval Complete, Setpoint Reached, and Error will trigger the SRQ if it is enabled. The Status Byte is replicated as byte 01 in the Error/Status String. See Section 7.8.3. 7.8.2 Error Byte The Error Byte is a one byte block of data in which each of the eight bits reports the status of an item. The bits in the Error Byte report the status of the following items: BIT ITEM 7 Time-out error. Chamber or platform did not reach a GT command temperature in 20 minutes. 6 Not Used 5 Undefined command.
byte 01 (status byte replica), the first 32 bytes (256 bits) are “event triggered”. The second 32 bytes (256 bits) are “status” or “state set”. Except for bits 0, 1 & 2 of the byte 01 (status byte replica), each of the bits in bytes 0-31 are set once when the condition that that bit reports becomes true. If the condition becomes false, the bit remains set.
Error/Status String Bit Definitions 00:0 00:1 00:2 00:3 00:4 00:5 00:6 00:7 Byte 00 - Duplicate of Error Byte First Release Used Aux input TTL high (Door open with optional switch) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.1 Error in Extended Error String . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.3.1 Illegal argument string . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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8. SETUP MODE Setup mode is entered by placing the mode switch in the right most position. Setup mode is used to modify operational parameters of the chamber. When first entering Setup mode, the digital display should display: f-0 n (n = 1 to 10) This first display indicates the setting for field 0. There are thirty parameter fields which can be modified. Table 8.1 shows the meaning of each field and the values each field can be assigned. T A B L E 8.
Field # Permitted Field Values Factory Setting Adjustment not normally required 5-7 Default = 5 Seconds required for D term effect to equal P term effect Adjustment not normally required 5-7 Default = 5 12 PID controller, integral wind-up limiter term Adjustment not required 7 13 Refrigeration compressor front panel control 1=yes 0=no 0-1 0 14 Autostart in Local Mode 1=yes 0=no 0-1 0 15 Blower shut-off mode 0=disable 1=enable 0-1 0 16 Temperature Scale 0=Celsius 1=Fahrenheit 0-1 0
Field # Field Purpose Permitted Field Values Factory Setting 25 Chamber/Platform Lower Operating Temperature Limit -200/C -327.9/F As required Default = -100 26 Chamber/Platform Upper Operating Temperature Limit 500/C 932/F As required Default = 200 27 Unit Under Test (UUT) Lower Operating Temperature Limit -200/C -327.
8.2 Changing the Value of a Setup Field A field may be changed with the following procedure: 1. Display the field to be changed using the key as detailed in 8.1. 2. Press to clear the current value. 3. Enter the new value Note: For setup parameters F0-F16, the valid choices may be scrolled by using and/or <+/-> until the desired field value appears on the display. If you wish to use this method, do not press first. 4.
Autostart is enabled, moving the mode from OFF to LOCAL will cause the controller to begin controlling to the last set local mode setpoint without the necessity of pressing . If the system includes mechanical refrigeration, and the last local control session had the compressor turn on, it will be turned on for the Autostart session as well. 8.
ice water (0/C) and boiling water (100/C) when the display shows 2.3/C for the ice water and 99/C for the boiling water, the user would enter the following: U1 C1 U2 C2 2.3 0 99 100 The C4 will then calculate a new slope and offset for the probe curve. All temperatures reported by the corrected probe will be adjusted by applying this new slope and offset to the raw temperature data reported by the probe. Note: Software probe correction is done separately for each probe.
If the values entered do not comply with the rules as defined above, the display cor err will show . None of the data will have been stored in this case and the process must be begun again with data that complies with the rules. C4 Manual Rev 7.5.
C4 Manual Rev 7.5.
9. APPENDIX 9.1 Programming Examples & Notes 9.1.1 Simple Local Program Example The following temperature test routine uses basic temperature control commands including controlled and maximum rate ramping and temperature hold (dwell): Using Probe 1 for control... Use 5 minutes to ramp from ambient to 45.2/C Hold 45.2 for 2 minutes Use 2 minutes to ramp to 32.3/C Hold 32.3/C for 6 minutes Go to 50.
Step Number 0 1 2 3 90 Displayed Step . Substep 00.0 00.1 00.2 00.3 00.4 01.0 01.1 01.2 01.3 01.4 02.0 02.1 02.2 02.3 02.4 03.0 03.1 03.2 03.3 03.4 Keys to press Description of entry CLEAR/ENTRY 45.2 ENTER Go to 45.2/C CLEAR/ENTRY 5 ENTER Use 5 minute ramp time CLEAR/ENTRY 2 ENTER Hold temperature for 2 minutes CLEAR/ENTRY 1 ENTER Execute step 1 next CLEAR/ENTRY 1 ENTER Use probe 1 CLEAR/ENTRY 32.3 ENTER Go to 32.
9.1.2 Using shortcuts to shorten program entry time Shortcuts can make program entry easier and faster if the program step memory to be used for the new program contains the values that you need. Default reinitialization values are stored in every program step when program memory is “cleared” by pressing to reinitialize program memory. These default values are often what you need.
Step Number 0 1 2 3 Displayed Step . Substep 00.0 00.1 00.2 00.3 00.4 01.0 01.1 01.2 01.3 01.4 02.0 02.1 02.2 02.3 02.4 03.0 03.1 03.2 03.3 03.4 Keys to press Description of entry CLEAR/ENTRY 45.2 ENTER Go to 45.2/C CLEAR/ENTRY 5 ENTER Use 5 minute ramp time CLEAR/ENTRY 2 ENTER Hold temperature for 2 minutes DISP/CNTL Accept default value of 1 DISP/CNTL Accept default value of 1 CLEAR/ENTRY 32.3 ENTER Go to 32.
9.1.3 Local Program Example Using the Special Commands The following temperature test routine uses program looping commands and the special port control commands: Turn chamber or platform (or auxiliary load) on Do the following loop 5 times Using probe 2 for control... Turn compressor on Use 15 minutes to ramp from ambient to 11.5/C Hold 11.5 for 20 minutes Use 1 hour to ramp to -32.3/C Hold -32.
Step Number 2 3 4 5 6 94 Displayed Step . Substep 02.0 02.1 02.2 02.3 02.4 03.0 03.1 03.2 03.3 03.4 04.0 04.1 04.2 04.3 04.4 05.0 05.1 05.2 05.3 05.4 06.0 06.1 06.2 06.3 06.4 Keys to press Description of entry CLEAR/ENTRY 11.5 ENTER Go to 11.5/C CLEAR/ENTRY 15 ENTER Use 15 minute ramp time CLEAR/ENTRY 20 ENTER Hold temperature for 20 minutes DISP/CNTL Accept default value of 3 Execute step 3 next CLEAR/ENTRY 2 ENTER Use probe 2 CLEAR/ENTRY -32.3 ENTER Go to 32.
Step Number 7 8 Displayed Step . Substep 07.0 07.1 07.2 07.3 07.4 08.0 08.1 08.2 08.3 08.
Once you have set the program pointer to a step, you can enter new program information by following the procedure in Section 6.4 or run a program that begins at that step as detailed in Section 6.7. IMPORTANT: When placing more than one program in memory, all programs except the last one must end with SUBSTEP 3 = 100, or a non terminating loop, in order to prevent separate successive programs from automatically running successively.
9.3 Sigma Systems C4 Programming Worksheet (O.K. to copy) Date: Step Program Name: SubStep Substep Data Page Notes/Comments Step SubStep .0 .0 .1 .1 .2 .2 .3 .3 .4 .4 .0 .0 .1 .1 .2 .2 .3 .3 .4 .4 .0 .0 .1 .1 .2 .2 .3 .3 .4 .4 .0 .0 .1 .1 .2 .2 .3 .3 .4 .4 C4 Manual Rev 7.5.
9.4 Sample Command Structure for IEEE-488 GPIB Operation All sample commands are written in BASIC for a Hewlett Packard 85F computer and are representative of the required structure for proper operation of the C4's IEEE-488 interface. Assumptions: C4 address is set to 1. All options have been implemented.
GT - Go To Temperature OUTPUT 701 "GT 85.0" OUTPUT 701 "GT 85" OUTPUT 701 "GT85" or or DL - Delay OUTPUT 701 "DL 00,25" OUTPUT 701 "DL00,25" RA - Ramp to Temperature OUTPUT 701 "RA 85.
9.5 Installation and Use of TTL Outputs and Input The C4 has incorporated in it the ability to receive one TTL signal and send two TTL signals. Throughout the manual, the outputs are referred to as AUX/POWER CONTROL PORT and REFRIGERATION COMPRESSOR PORT. The input is referred to as the AUX INPUT (previously known as the DOOR SWITCH). These signals are available on the "B" circuit board (the one with the 6 lug screw terminal strip on the back.
If the controller is equipped with internal solid state relay to control the compressor, the output of the solid state relay is through pin 8 of P1, the 12 pin power cable to the controller. At the end of running a program from the front panel, the chamber control port and the compressor control port will return to their original default positions of high and low, respectively. 9.
3. Remove probe connections at the controller's rear terminal strip, J1-1 and J1-4. 4. Locate test points TP1 and TP6 (TP2 on CC-3.5) and adjustments R5 (R29 on CC-3.5) and R2 (R32 on CC-3.5) in the upper rear area of the right hand circuit board (B- board see fig.). 5. Apply power to unit and turn power switch on. 6. * With nothing hooked to the probe inputs of the controller, adjust R5 (R29) until the voltage at TP1 reads 7.100 volts +\- 0.005 .
9.7 Troubleshooting 9.7.1 Servicing Considerations - Service WARNINGS WARNING: Sigma Systems C4 Controllers obtain power from the chamber or platform to which they are connected. The controllers do not have protective side covers on the chassis. It is imperative to disconnect the power to both the chamber or platform and the controller (if separate) from the power source before removing the controller. Look for an optional separate power cord going to the controller.
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.
Explicit Program End If you are observing behavior that indicates that the controller is continuing to control beyond the end of the steps you have in your program, check to be certain that you have a step at the end of your program that points to step 100 to end the process. Otherwise, if there are some unused steps further up in program memory, they may be getting executed in error.
If you are having no success with bus communications, check to be certain that the correct bus (EIA-232 or GPIB IEEE-488) is selected using setup parameter F2. SI (Immediate Mode) or the default SP (Program Mode) are typically issued at the beginning of a program sequence. However they may be issued at any point. If the C4 receives a SI command and there is a command executing and/or commands in the command buffer, the executing command is interrupted and the command buffer is cleared.
unlikely that a problem will cause a bad load, but it is possible and it’s the easiest problem to fix, so try reloading first. Starting the C4 from PROM based firmware If reloading doesn’t work, you can try starting the controller from the older firmware that permanently resides on the PROM in the controller. To initiate a PROM based startup, press rapidly three times while the model number is displayed (very first display upon power up).
Proportional term Integral term Differential term Setup parameter F0 Setup parameter F10 Setup parameter F11 Note that you will also find the in setup section of this manual a reference to the Integral Wind-up Limiter Term (Setup parameter F12). Do not alter this field. It is set once at the factory for the C4 model controller and never requires adjustment. Adjusting for changing needs.
Before you change any of the PID terms in your C4, write down the existing values. It is not hard for inexperienced users to make enough changes that things get much worse. If this happens to you, you will want to have a list of the original settings so you can at least go easily back to what you had. If you forget to write the setting down, or if your controller was way off to begin with, we suggest that you start with the default settings as shown in Section 8, Setup Mode.
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.
9.9 Displayed Messages and Errors Table Display Description Manual Section 06.0 -30.5 Program step display 6.1 200 - 100c Controller range - Celsius mode 3.1.2 392 - 148f Controller range - Fahrenheit mode 3.1.2 4-0 3276 Controller serial number 3.1.3 7.5.2 Controller firmware version 3.1.1 all res Full memory reset 3.7.2 c3-5 Model number 3.1.1 clr Clearing program steps 6.2 cor err Probe correction data entry error 8.7 del Deleting program step 6.
res err Watchdog timer reset 3.7.1 rs load Ready to upload firmware 3.2.2 s1 -77.7 Setpoint for probe 1 control 5.2 sor System Operating Range error 5.2, 6.7.2 sp err Setpoint error 5.3 su res Setup parameter default value restore 3.3 su err Setup parameter table error 3.7.3 su done Finished writing to EEPROM 3.3 u1c 65.3 or u1f 102.7 Idle after quit command 7.7.9 or -sor 9.
INDEX 2 probe control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Autostart mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80, 82 Aux/power control port Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Cryogenic boost control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
QC Query last command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 QE, QEA Query error/status string . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 QF, QFA Query setup parameter value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 QN Query controller serial number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 QR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fail-safe System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11, 101 COM port issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Firmware upload problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 Starting the C4 from PROM based firmware . . . .
WP Set PID constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 PN Select active (control) probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Aux/power control port control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 connector . . . . . . . . . . . . . . . . . . .
Local program example using the special commands . . . . . . . . . . . . . . . . . . . 91 Multiple in memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Programming worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Using shortcuts to shorten program entry time . . . . . . . . . . . . . . . . . . . . . . . 89 Program mode problems Blowers misbehaving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RS, RSA - Request status byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 RS-232 See EIA-232 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Run Time Pre-read Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Invalid Loop Count Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 No Probe 2 Error . . . . . . . . . . . . . . . .
Shutdown conditions Internal error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Memory signature failed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Probe out of range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Setup parameters corrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Differential Term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 The integral term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 The proportional term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 WP Set PID constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 UP Write current parameters to NV memory . . . . . . . . . .