Marathon Computer AACC 2000 manual Motorized valve control

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Marathon Monitors Inc.

Motorized valve control

The AACC 2000 can be configured for motorised valve control as an alternative to the standard PID control algorithm. This algorithm is designed specifically for positioning motorised valves.

These are ordered pre-configured as Model numbers:

∙2000/VC motorised valve controllers

∙2000/VP motorised valve controllers with a single setpoint programmer

∙2000/V4 motorised valve controllers storing four setpoint programs.

∙2000/VM motorised valve controllers storing twenty setpoint programs.

Figure 1-11 in Chapter 1 shows how to connect a motorised valve controller. The control is performed by delivering open, or close, pulses in response to the control demand signal.

The motorised valve algorithm can operate in one of three ways:

1.The so-called boundless mode, which does not require a position feedback potentiometer for control purposes; although one can be connected and used purely to display the valve’s position.

2.Bounded, (or position), control mode, which requires a feedback potentiometer. This is closed-loop control determined by the valve’s position.

The desired control mode is selected in the ‘inst’ list in configuration level.

The following parameter list will appear in the navigation diagram shown in Chapter 2, if your controller is configured for motorised valve control.

Name	Description			Values

mtr	Motor list	Min			Max	Default
tm	Valve travel time in seconds.	0.1			240.0	30.0
	This is the time taken for the valve to travel
	from its fully closed position to its fully open
	position.

In.t	Valve inertia time in seconds.	OFF			20.0	OFF
	This is the time taken for the valve to stop
	moving after the output pulse is switched off.

bAc.t	Valve backlash time in seconds.	OFF			20.0	OFF
	This is the minimum on-time required to
	reverse the direction of the valve. i.e. the
	time to overcome the mechanical backlash.

mp.t	Output pulse minimum on-time, in seconds.	Auto			100.0	Auto

U.br	Valve sensor break strategy.	rESt, uP, dwn				dwn

AACC 2000 Carbon

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Nov. 1, 1997

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Contents Copyright Marathon Monitors INC Marathon Monitors Inc Mechanical Installation Electromagnetic compatibility SafetyElectrostatic discharge precautions CleaningPersonnel Safety SymbolsWiring Power IsolationConductive pollution Over-temperature protectionOvercurrent protection Voltage ratingRouting 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 ModelUnplugging and plugging-in the controller To install the controllerIntroduction Controller labelsModel 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 26.0SP2 Button or Name ExplanationOP1 OP2Basic operation AlarmsOperating modes Display units Automatic modeOutput power demand Home displaySetpoint 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 Adc TunEDrA DrA.tHcb Pid PID listSEt RESInput 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 Hiding or revealing a complete list Setting operator access to a parameterEdit level Returning to Operator LevelPromoting 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 LevelSB.OP REULIN D1SA EnabNone RelyCMS YES DIGPMV SP.FF InSt Instrument configurationName Description Values Meaning H2OCJC 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 User calibration Password configurationExit Exit configuration DC Output CalibrationUser calibration Exit configuration User Calibration EnableCalibration Configuration List User Calibration EnableCalibration 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