06062017 Binary Logic Systems Chapter 06 Binary Logic

06/06/2017 Binary Logic Systems Chapter 06 – Binary Logic Systems EMEC 125 Why Binary Logic Systems? • Documents need to be understood by people with very different backgrounds. People who could need the documentation are: • • Management Process Designers Operations Staffs Maintenance Technicians Electrical and Control System Professionals Logic Device Programmers Supervisory Control and Data Acquisition (SCADA) System Configurators Binary Logic Diagrams • ISA-5. 2 -1976 (R 1992) Binary Logic Diagrams for Process Operations and Scientific Apparatus Makers Association (SAMA) PMC 22. 1 Functional Diagramming of Instrument and Control Systems. Both address binary logic diagrams. • Elements of these standard are now included in ANSI/ISA-5. 1 1

06/06/2017 Terms You Should Know Before Proceeding • Discrete Control • “On/off control. One of the two output values is equal to zero. ” (International Society of Automation, 2003, p. 150) • A better definition would be: A signal that is either fully ON or fully OFF with no values in-between. • Binary • “ 1. A term applied to a signal or device that has only two discrete positions or states. When used in its simplest form, as in “binary signal” (as opposed to “analog signal”), the term denotes an “on-off” or “high-low” state, that is, one that does not represent continuously varying quantities. [ANSI-ISA-5. 1 -1984 (R 1992)]. ” (International Society of Automation, 2003, p. 49). Terms You Should Know Before Proceeding • Analog • “ 1. Having the form of continuously variable physical quantities, as in data. Contrast with digital. 2. The representation of numerical quantities by means of physical variables, such as translation, rotation, voltage or resistance. 3. A waveform is analog if it is continuous and varies over an arbitrary range. Contrast with digital. ” (International Society of Automation, 2003, p. 21). • Another way to define Analog is: A continually varying signal that can be fully ON, fully OFF or any level in between. (International Society of Automation, 2003, p. 21). Terms You Should Know Before Proceeding • Process Variable • “ 1. Any variable property of a process. The term process variable is used in the relevant standard to apply to all variables other than instrument signals [ANSI/ISA-5. 1 -1984 (R 1992)]. 2. In the treatment of material, any characteristic or measurable attribute whose value changes with changes in prevailing conditions. Common variables are flow, level, pressure and temperature. ” (International Society of Automation, 2003, p. 392). • Control Variable (Controlled Variable) • “ 1. The variable that the control system attempts to keep at the set point value. The set point may be constant or variable. 2. The part of a process to be controlled (flow, level, temperature, pressure, etc. ). ” (International Society of Automation, 2003, p. 109). 2

06/06/2017 Combining Analog and On-Off Control • Combining analog and on/off control schemes can be defined by using: • • Process control descriptions Instrument diagrams Functional diagrams Electrical schematic diagrams • These documents can be used independently or together depending upon the phase of design, construction or operation. Process Control Descriptions • The more complex the process, the more detail that is required in a Process Control Description. The following areas to be included, but not limited to, in a Process Description: • Process Description • Title of the system • General description • Form • Control Description • More specific data on how the system will perform • Loop-by-loop descriptions • Format The Binary Concept – Multiple Input • This two-state binary concept, applied to gates, can be the basis for making decisions in ladder logic. • The gate is a device that has one or more inputs and one output. • The gate will perform a logical decision based on the status of its inputs and produce a result at its one output. 3

06/06/2017 Using Gates to Make Decisions • The logical AND gate or function. • All inputs must be true to obtain an output. Air Conditioner Switch Blower Switch AND Gate Cold Air The automotive air conditioning to work, the Air Conditioner must be turned on and the Blower must be turned on. Using Gates to Make Decisions • The logical OR gate or function. • Any one input must be true to obtain an output. Passenger Door Switch OR Gate Dome Light Driver Door Switch The automotive dome light will be on when the passenger door OR the driver door or both door switch(s) is activated. The AND Function • The AND function has two or more inputs and one output. The input signals are labeled A, B, C, etc. and the output signal is labeled Y. • A binary 1 represents the presence of a voltage (signal). A binary 0 represents the absence of voltage (no signal, 0 V or ground). • Logic functions can be represented using a truth table. The truth table lists all possible input status conditions with the corresponding output status for each set of input condition. A B Inputs AND Gate Output Y Two input AND gate 4

06/06/2017 An AND Gate Application • An AND gate functions like switches in series. • The light will only be ON when switch A AND switch B are both closed. PB 1 = 1 PB 2 = 1 AND Gate LT 1 ON The OR Function • The OR function has two or more inputs and one output. The input signals are labeled A, B, C, etc. and the output signal is labeled Y. • A binary 1 represents the presence of a voltage (signal). A binary 0 represents the absence of voltage (no signal, 0 V or ground). • Logic functions can be represented using a truth table. The truth table lists all possible input status conditions with the corresponding output status for each set of input condition. OR Gate A Inputs B Output Y Two input OR gate An OR Gate Application • An OR gate functions like switches in parallel. • The light will be ON when either or both switch A OR switch B are closed. PB 3 = 1 PB 4 = 0 OR Gate LT 2 ON 5

06/06/2017 The NOT Function (Inverter) • The NOT function gate, also called an inverter, has one input and one output. • The NOT gate functions like its name states, it inverts the input signal status. • If the input is a 1 the output is a 0. • If the input is a 0, the output is a 1. A Input A (not A) A NOT Gate Application • The NOT gate functions like a normally closed switch. • The light will be ON if the switch is NOT being activated and OFF when the switch IS being activated. PB 5 Input PB 5 (not PB 5) The NAND Function • The NAND gate functions like an AND gate with an INVERTER on its output. • The only time that the output of a NAND gate is a 0 is when all the inputs are a binary 1. PB 6 PB 7 NAND Gate Light Two input NAND gate 6

06/06/2017 The NOR Function NOR Gate PB 8 • The NOR gate functions like an PB 9 OR gate with an INVERTER on its output. LT 5 Two input NOR gate • The only time that the output of a NOR gate is a 1 is when all the inputs are a binary 0. The XOR (Exclusive- OR) Function • The XOR gate has two inputs and one output. • The output of this gate is a 1 when the two inputs are opposite to each other. Therefore, one input a 1 and the other a 0. • The output of this gate is a 0 when both inputs are the same, either two 0’s or two 1’s. XOR Gate PB 10 PB 11 LT 6 AND Gate Circuits Electromechanical Ladder Diagram PLC/PAC Ladder Diagram LS 10 A Inputs AND Gate Output SOL 010 Two input AND gate 7

06/06/2017 OR Gate Circuits Electromechanical Ladder Diagram PLC/PAC Ladder Diagram LS 011 LS 012 Inputs OR Gate Output Sol 011 Two input OR gate Combinations of Gates Electromechanical Ladder Diagram PLC/PAC Ladder Diagram OR Gate LS 013 LS 014 Inputs AND LT 013 Output Gate CR Combination of Gates Electromechanical Ladder Diagram PLC/PAC Ladder Diagram LS 015 LS 016 OR Gate AND Gate Inputs CR 01 CR 02 OR Gate LT 016 Output 8

06/06/2017 Combination of Gates Electromechanical Ladder Diagram PLC/PAC Ladder Diagram LS 017 LS 031 AND Gate Output OR Gate Inputs LS 018 AH 017 Combination of Gates Electromechanical Ladder Diagram PLC/PAC Ladder Diagram PB 019 PB 020 AND Gate OR Gate Inputs PB 021 PB 022 AND Gate Output LT 019 Combination of Gates Electromechanical Ladder Diagram PLC/PAC Ladder Diagram Why is this instruction programmed open? CR 6 Inputs CR 6 AND Gate SOL 021 Output LS 021 9

06/06/2017 Combination of Gates Electromechanical Ladder Diagram Why are these instruction programmed open? PLC/PAC Ladder Diagram This is an XOR circuit Combination of Gates Electromechanical Ladder Diagram Draw the PLC/PAC ladder diagram for this logic A B OR Gate Inputs AND Gate C D M Output Control Description (From ANSI/ISA-5. 1) • Control system design for: • Small volumes for long and short periods should allow tank to fill to a high level to automatically start the pump and then to stop the pump at a low level. • Large volumes for long periods should allow the pump t run continuously and maintain a fixed level with a level-to-flow cascade control loop. • Pump (run, or operation) control is selected by a three-position Hand-Off. Auto (H-O-A) selector switch: • Selector switch is in “HAND” position. • Selector switch is in “AUTO” position. • Pump should be stopped at any time: • Automatically if low level is exceeded. • By operation the stop pushbutton. • Switching the H-O-A selector to “OFF” position. ISA 5. 1 (2009). pdf 10

06/06/2017 Instrument Diagram STOP HS LIC *02 -B *02 START LT *02 T-1 LSL *02 HS HS *02 -A *01 LSH *02 FIC H-O-A *01 FT FV *01 FO P-1 Functional Diagram Symbols Measuring, Input, or Readout Device [*] = Instrument Tag Number Symbols from Table 5. 5 in the ANSI/ISA- (*) 5. 1 -2009 Standard Automatic single-mode controller (*) Automatic two-mode controller (*) (*) Automatic single controller (*) Manual signal processor (*) Final control element Control valve (*) Final control element with positioner Control valve with positioner Binary Logic – AND & OR Gates A B C A N D AND Y A B C Y OR A B C Y 0 0 0 1 1 0 0 0 1 0 1 1 1 A B C Y 0 0 0 1 1 0 1 0 1 1 0 0 1 1 1 1 0 1 11

06/06/2017 Binary Logic – NOT & Memory NOT A A A 0 1 1 Memory 0 A B C D 1 0 0 0 1 2 1 0 3 0 0 1 0 1 A S C 4 B R D 5 0 0 0 1 6 1 1 1 0 7 0 0 1 0 8 1 1 0 1 Electrical Schematic – Ladder Diagram START HS*02 -A M 1 STOP HS*02 -B H O A LSL*02 M OL M 2 LSH*02 Logic Diagram Example Electrical Logic STOP STAR T COIL OVERLOAD R ELAY CONTACTS Pump Start Pump Stop Motor Starter, Pump Motor Overload A N D N OT S Pump Starts N OT R Motor Starter, Reset Pump Motor 12

06/06/2017 Function Block Diagram – Allen Bradley (FYI) Function Block Diagram – Siemens (FYI) Functional Diagram LSH*02 FT *01 LT *02 ‘ 1’ when at High Level H A T Δ P A HS *01 Δ I T A N D A P A START I T A N D HS A *02 -A LSL*02 f((*x)) STOP FV*01 HS *02 -B L ‘ 1’ when NOT at Low Level S OL H-O-A H A N D Ro OR PUMP P-1 S Ro A N D NOT OL A N D This diagram literally sucks – SU QU E 13

06/06/2017 Functional Diagram ‘ 1’ when at High Level M 2 LSH*02 FT *01 LT *02 H A Δ P A T Δ I T P A I T A A LSL*02 f((*x)) HS *01 L H ‘ 1’ when NOT at Low Level Pump H-O-A FV*01 STOP OL HS *02 -B START HS *02 -A M 1 Lab. Volt Electrical Convert Ladder to Logic Gates 14

06/06/2017 Convert Ladder to Logic Gates Convert this Logic to Ladder Summary • This chapter discussed discrete control (on/off control) in a process plant. • Logic diagrams will aid in the understanding of how Safety Instrumented Systems (SIS) work. • Functional diagram symbols were discussed along with an example of how they are used. • Basic logic gates have been discussed, along with the symbols used to represent them. 15

06/06/2017 References CEmark. com & European. Authorized-Representative. eu. (1996 -2015). What is CE Marking (CE Mark)? Retrieved June 17, 2015, from Welkang Tech Consulting: http: //www. ce-marking. org/what-is-cemarking. html Charlet, T. (2016, September 8). How to Replace an Evaporator Temperature Sensor (Switch). Retrieved November 22, 2016, from Your Mechanic: https: //www. yourmechanic. com/article/how-to-replace-anevaporator-temperature-sensor-switch-by-timothy-charlet International Society of Automation. (2003). Automation, Systems, and Instrumentation Dictonary(4 th ed. ). Research Triangle Park: International Society of Automation. Retrieved from http: //app. knovel. com/hotlink/toc/id: kp. ASIDE 005/automation-systems-instrumentation/automationsystems-instrumentation International Society of Automation. (2009, September 18). ANSI/ISA-5. 1 -2009 Instrumentation Symbols and Identification. American National Standard. Research Triangle Park, North Carolina: International Society of Automation. Kirk, W. F. , Weedon, A. T. , & Kirk, P. (2014). Instrumentation and Process Control(6 th ed. ). Orland Park, Illinois: American Technical Publishers. References Lipták, G. B. (Ed. ). (1995). Process Measurement and Analysis (3 rd ed. ). Radnor, Pennsylvania: Chilton Book Company. Mc. Avinew, T. , & Mulley, R. (2004). Control System Documentation Applying Symbols and Identification(2 nd ed. ). Research Triangle Park, North Carolina, USA: International Society of Automation. Meier, F. A. , & Meier, A. C. (2011). Instrumentation and Control Systems. Documentation (2 nd ed. ). Research Triangle Park, North Carolina: International Society of Automation. Ruelas, E. (2016, January 6). Symptoms of a Bad or Failing AC Control Switch. Retrieved September 8, 2016, from Your Mechanic: https: //www. yourmechanic. com/article/symptoms-of-a-bad-or-failing-ac-control- switch Shutterstock. (n. d. ). Car Air Conditioner. Retrieved September 8, 2016, from Shutterstock: https: //www. shutterstock. com/search/car+air+conditioner Sourceingmap. (n. d. ). Car Vehicle Interior Door Courtesy Light Switch Button Part. Retrieved September 8, 2016, from Amazon. co. uk: https: //www. amazon. co. uk/Vehicle-Interior-Courtesy-Switch-Button/dp/B 00 B 0 QLVSS References Wu, E. (2012, June 18). 2011 Chevy Camaro equipped with LED Interior. Dome Lights. Retrieved September 8, 2016, from i. JDMTOY Blog for Automotive Lighting: http: //ijdmtoy. com/BLOG/wordpress/2012/06/18/2011 -chevycamaro-equipped-with-led-interior-dome- lights/ Thomas, E. C. (2015). Introduction to Process Technology(4 th ed. ). Boston, MA: Cengage Learning. 16