Sanyo 550 Appendix 1 Technical Specification, Operator interface data entry, Control Loops

APPENDIX 1 - TECHNICAL SPECIFICATION

Temperature & Humidity Programmer/Controller with inbuilt Logic, chamber

intelligence mapping, & Data Logging

Operator interface data entry:	on-chamber dedicated numeric keypad,
display:	on-chamber (green) monochrome CRT.
Operating temperature:	5°C to 60°C.

Analogue inputs Two 4 wire PRT inputs. Range -150°C to +350°C. Accuracy +/- 0.1°C. Dedicated to measuring temperature and humidity (relative humidity is de- rived by wet & dry bulb by psychrometric computation).

Calibration of the analogue inputs: performed in software; there are no presets to ad- just.

Control Loops

Temperature. Three term (P.I.D.) digital control, using trapezoidal approximation to in- terpolate between samples. Input sample and control period is 4 seconds. Output of control algorithm is heat digital mark space ratio (with -100% to +100% dead band adjustment). Set point resolution 0.loC.

Relative Humidity. Three term (P.I.D.) digital control, using trapezoidal approximation to interpolate between samples. Input sample and control period is 4 seconds. Out- put of control algorithm is humidify digital mark space ratio (with -100% to +100%

dead band adjustment). Set point resolution 1 %RH.

Controller Intelligence For all regions of the chamber performance envelope, a table pre-stores:

a map of appropriate "housekeeping" facilities

a map of appropriate P.I.D. controller coefficients.

Maps are not displayed on the controller. Housekeeping: Digital channel selection: by autosuggestion from intelligence at setpoint entry. Over-ride: available at keypad.

Internal Defrost Clock: Invoked automatically if required (from intelligence).

Steady State Control The controller allows set point values to be entered for tempera- ture and humidity. With autosuggested or manually input digital channel selections.

Programs

Library capacity: 20 programs nominal (leaves space for 1 week log) program size: 150 lines/segments max per program, 10 kbytes approx per program, segment/line con- tent: time + any of: temperature, humidity, digital channel, loop

time basis: time from program start

time units: days, hours, minutes, seconds

editing facilities: line cut; paste; block copy

loop: facility to repeat program sections

nesting: (loops within loops) supported

file facilities: save, load, delete

precondition: line 000 omits after 1st cycle.

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