Marathon Computer AACC 2000 manual Two-point calibration, Displayed Value

Page 89

Marathon Monitors Inc.

Two-point calibration

The previous section described how to apply a offset, or trim, calibration, which applies a fixed offset over the full display range of the controller. A two-point calibration is used to calibrate the controller at two points and applies a straight line between them. Any readings above, or below, the two calibration points will be an extension of this straight line. For this reason it is best to calibrate with the two points as far apart as possible.

Displayed Value		Offset introduced
				User Calibration
Calibration high-point value				Factory Calibration
Calibration high-point value				Factory Calibration
High-point calibration				x
Low-point calibration				x
		x

Calibration low-point value
Calibration low-point value

Offset introduced

Proceed as follows:

1.Decide upon the low and high points at which you wish to calibrate.

2.Perform a two point calibration in the manner described below

Input list header

Press until you reach the input list header, ‘ip LiSt’.

Press until you reach the ‘CAL’ display.

Calibration type

x 3	∙	FACt:	Factory Calibration

	∙	USEr:	User Calibration

Use or to select ‘USEr’.

Selecting ‘USEr’ enables two-point calibration.

[If two-point calibration is unsatisfactory, select ‘FACt’ to return to the factory set calibration.]

Press

AACC 2000 Carbon

89

Nov. 1, 1997

Image 89

Contents Copyright Marathon Monitors INC Marathon Monitors Inc Mechanical Installation Electrostatic discharge precautions SafetyCleaning Electromagnetic compatibilityWiring Safety SymbolsPower Isolation PersonnelOvercurrent protection Over-temperature protectionVoltage rating Conductive pollutionRouting of wires Installation requirements for EMCGrounding of the temperature sensor shield Equipment ratings Environmental ratingsGeneral Electrical safetyMarathon Monitors Inc Installation Outline dimensions Model 2000 controller Outline dimensions ModelIntroduction To install the controllerController labels Unplugging and plugging-in the controllerModel Aacc 2000 rear terminal layout Rear terminal layoutsMarathon Monitors Inc Module 1, 2 Sensor input connectionsSnubbers Two terminal modulesDual output modules Four terminal modulesCOM Connections for Process Value 2 PV2 Connections for Process Value 3 in module positionCommunication module EIA-485 wiring Wiring of 2-wire EIA-485 serial communications linkMarathon Monitors Inc Operation Front Panel LAYOUTs 26.0OP1 Button or Name ExplanationOP2 SP2Basic operation AlarmsOperating modes Output power demand Automatic modeHome display Display unitsSetpoint Manual ModeList header displays Parameters and HOW to Access ThemMarathon Monitors Inc To change the value of a parameter Parameter namesParameter displays OFF List1OFF PID.1 PIDSTD FactPass Hydrogen or CO constant Name Description Prob Probe list Process FactorMillivolt input Offset Name Description DrA TunEDrA.t AdcSEt Pid PID listRES HcbInput list Setpoint listInFo Information list Output listCmS Comms list FF.OP Access ListAlarms Display What it means What to do about it Shows Diagnostic alarms2b Diagnostic alarms Access Levels Access to Read-only Configuration Access list headerPassword entry Level selection Configuration passwordConfiguration level Edit level Setting operator access to a parameterReturning to Operator Level Hiding or revealing a complete listPromoting a parameter This sheet intentionally left blank Parameter Code Meaning or Function TuningHow to tune One-shot TuningAdaptive tune Typical automatic tuning cycleCalculation of the cutback values Manual Tuning Proceed as follows Setting the cutback valuesAutomatic droop compensation Adc Integral action and manual resetMotorized valve control Name Description Values Mtr Motor list Min Max DefaultInertia and backlash settings Adjusting the minimum on-time ‘mp.t’Marathon Monitors Inc Set the transfer point Enable in configuration levelGain scheduling Configuration Press to enter configuration Selecting configuration levelChanging the passwords Leaving Configuration LevelLIN REUD1SA Enab SB.OPNone RelyCMS YES DIGPMV Name Description Values Meaning InSt Instrument configurationH2O SP.FFCJC Process value configInput configuration VAL.H Setpoint configurationVAL.L Alarm Modes Alarm configuration ValuesTable a Alarm types Value IMP Digital input 1 configuration Action on contact closureDigital input 2 configuration Action on contact closure Pflt Alarm relay configurationVflt Combining several digital events on to one output Comms 1 module configCool Module config1A b C1 Module 1 configuration For ‘id’ = ‘LoG.i’ i.e logic input use the LA Conf’ list on 2A/b/C Module 2 configurationDisplayed value low SEL 3A/b/C Module 3 configurationModule configuration C Module configurationVAL.8 Point Custom LinearisationVAL.1 CAL Exit Exit configuration Password configurationDC Output Calibration User calibrationUser calibration Calibration Configuration List User Calibration EnableUser Calibration Enable Exit configurationCalibration type Offset calibrationInput list header Set Offset See table on the right for additional parametersDisplayed Value Two-point calibrationSelect Low-point Calibration Adjust low-point calibrationSelect High-point Calibration Adjust High-point CalibrationName Parameter description Meaning Calibration points and Calibration offsetsParameter Table Default HY1 Ssel FLT3 Marathon Monitors Inc AL1 Module 2A High Value VAL.1 101 Index Two-point calibration User calibration Aacc 2000 Carbon