ABB SM2000 User Manual Supplement

Also see for SmartMedia SM2000: Installation instructions User guide supplement User guide User guide User guide

Contents

ABB SM2000 User Manual Supplement Manual pdf 17 page image

153 LOGIC CONFIGURATION3.1 Logic Equation DescriptionNote.• 12 logic equations• Up to 6 operands and 5 operators per equation• OR/AND/NOR/XOR/NAND/NOT operators – seeTable 3.1 overleaf• Can combine internal and external digital signals– i.e. alarms, digital inputs, other logic equationresults and real time events (timer option).Note. Elements on each equation are calculated sequentially.3.2 Worked Example – Reservoir Level Control– Fig. 3.1Note. This example uses an optional Hybrid I/O Modulein position C – see Appendix 5.• Channel 1.1 records the reservoir level, with anengineering range 0 to 100 feet.• Alarms 1.1A, 1.1B and 1.2A monitor the reservoirlevel.• Digital output C6 to drive the control valve fromLogic Equation 1• Digital input C1 to operate the manual override.Fig. 3.1 Logic Equation Example• Alarm 1.1A – set to high process trip at 50 ft• Alarm 1.1B – set to high process trip at 80 ft• Alarm 1.2A – set to fast rate trip at 10% of range per hour(10 ft/hr)• Manual override switch:Connected to (optional) digital input B1Flow Conditions Input ElementsClose reservoir control valve if:• Reservoir level >50 feet AND rate of change >10 ft/hrOR• Reservoir level >80 ftOR• Manual override switch operated50feet80feetControlValveLevel SensorRelay OutputAlarm 1.1BAlarm 1.1ATimeLevelAlarm 1.2ARate ofchange> 3m/h (%'( *$+ *%(%'( '( )(%'( '(,)% -./0 12%,*$+ 3(%'( '( )*$+ *Alarm 1.1AAlarm 1.2AAlarm 1.1BDigital i/p C1AndOrOrEquation1resultManual Overide