Marathon Computer AACC 2000 manual Two terminal modules, Snubbers

Page 17

Marathon Monitors Inc.

Two terminal modules

Note:

Module 1 is connected to terminals 1A and 1B

Module 2 is connected to terminals 2A and 2B

Module 3 is connected to terminals 3A and 3B.

Terminal identity

Module type

A

B

C

D

Possible functions

Relay: 2-pin

Unused

Heating, cooling, alarm,

(2A, 264 Vac max.)

program event, valve raise,

or valve lower

Logic - non-isolated

+

Unused

Heating, cooling, mode 1,

(18Vdc at 20mA)

−

mode 2, program event

Triac

Unused

Heating, cooling, program

(1A, 30 to 264Vac)

event, valve raise, or valve

Line

Load

lower

DC output:

Unused

Heating, or cooling, or

+

−

- non-isolated

retransmission of PV,

(10Vdc, 20mA max.)

setpoint, or control output

Table 1-1 Two terminal module connections

Snubbers

The relay and triac modules have an internal 15nF/100Ω ‘snubber’ connected across their output, which is used to prolong contact life and to suppress interference when switching inductive loads, such as mechanical contactors and solenoid valves.

WARNING

When the relay contact is open, or the triac is off, the snubber circuit passes 0.6mA at 110Vac and 1.2mA at 240Vac. You must ensure that this current, passing through the snubber, will not hold on low power electrical loads. It is your responsibility as the installer to ensure that this does not happen. If the snubber circuit is not required, it can be removed from the relay module (BUT NOT THE TRIAC) by breaking the PCB track that runs crosswise, adjacent to the edge connectors of the module. This can be done by inserting the blade of a small screwdriver into one of the two slots that bound it, and twisting.

AACC 2000 Carbon	17	Nov. 1, 1997
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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