Mechatronics- PLC Download: http://skillcruise.com/academics/robotics-mechatronics/programmable-logic-controller-plc/

1. PLC - A detailed descriptionPLC - A detailed descriptionPLC - A detailed descriptionPLC - A detailed description

2. P.L.C.
Programmable Logic Controller
• CPU - Decision Making Unit
• Inputs-Digital/Analog/High Speed
• Outputs - Digital / Analog
• Power Supply - 24 VDC / 110VAC / 220VAC / +/- 12V
• Timers / Counters / Flags / Registers / Memory
• Communication - Serial - RS232C / Equivalent
• Programming - Through PC / Hand held Terminal / Programmer

3. Why to use PLCs ?
COST
PLC can scan Digital & Analog Inputs through relevant S . It can execute the
Logic w.r.t. the Scanned Inputs, take necessary decision and send it to
Digital / Analog Outputs. It can also perform PID control Functions. The cost
of all this is much less than a conventional DATA Logger !!
Versatility
The ability to combine discrete (Digital) & Analog logic is a powerful tool for
the Control Engineers. Control of critical start-up parameters, such as
temperature and pressure, can be precisely pre-programmed for each start-
up step.

4. Expandability
As a process matures, it is inevitable that enhancements will be needed.
These usually require more outputs.
For hard-wire Relays system this usually necessitates extensive panel changes,
which generally are problematic.
A PLC easily accommodates the additional I/O’s without requiring changes in
the existing wiring.
If a PID loop is to be added, no panel rework is necessary; only the wiring of
new points and some re-programming to incorporate them is required.
Why to use PLCs ?

5. Flexibility
•As a process goes ONLINE and Refined, the Control Equipment should be
easily reconfigured to accommodate such modifications.
• Bottling Plant Control, Traffic Light Control, Process Control of Temp., Pressure,
Level, Flow etc., Car Parking Control etc. are all within the Capabilities of
PLC’s.
•As one common device (PLC) performs multiple functions in a Plant, fewer
spare parts are needed .
•The Digital nature and self-Diagnostic capabilities are strong additional
justification for the PLC.
Why to use PLCs ?

6. Advantages of PLC over Electro-mechanical Relays
•Ability to interface / communicate with Computers
•Simple Programming
•Field Programming possible (HHT)
•High Reliability (Better MTBF)
•Easy Maintenance
•Rugged Construction - Can operate in Extremely harsh field conditions
•Smaller Size
•Easy Expandability (Due to Modular Design)
•Economical in Long Term

7. Differences between PLC & PC / Computers
• Real Time Operation - PLC’s are designed to operate in a REAL-TIME
control Environment. Most PLC’s have internal clocks and built-in “Watch-
Dog Timers”.

8. PLC’s Vs PC’s
•Environmental Conditions
PLC’s are designed to operate near the equipment they are meant to
control. This means that they function in hot, humid, dirty, noisy and dusty
industrial environments.
PLC’s can operate in 60 Deg C as well as 0 Deg C, with tolerable relative
Humidities ranging from 0% to 95% non-condensing.

9. Programming Languages & Techniques
•PLC - Ladder Diagram format is read & understood world-wide by
maintenance technicians as well as by engineers.
•Unlike Computer Programming, PLC Programming does not require
extensive special training.
•Programme operation are performed by the PLC in the order they were
programmed . This allows easy programming of Shift Registers
PLC’s Vs PC’s

10. • Maintenance & Trouble-shooting
• As PLC is a Plant Floor Controller it has to be maintained / serviced by
plant electrician or the Instrument Technician.
• It would be highly impractical to require computer type maintenance
service.
• Most PLC Components are modular and simple to isolate, remove-and-
place (system modules) diagnostic techniques are usually implemented.
PLC’s Vs PC’s

11. Digital I/O Devices
• Digital Input Field Devices
• Pushbuttons,
• Thumbwheel Swiches
• Limit Switches
• Selector Switches
• Proximity Sensors
• Photoelectric Sensors
• Digital Output Field Devices
• Discrete Outputs - Relays, Solenoids, Contactors, Motors starters,
Annunciator Windows, Pilot Lights etc.
• Register Outputs - Displays, Panel Meters etc.

12. Various Types of Transmitters

13. Analog I/O Devices
Analog Outputs
4 to 20mA / 0 to 5V DC –
Can drive signals to variable speed drives etc., Control Temperature, Pressure,
Level, Flow, pH, Conductivity etc.
Analog I/P
•4 to 20 mA / 0 to 5V DC
•12 Bit or better ADC
•32 Bit Storage (For SCADA)
•Thermocouples T/C / RTD’s
•Flow Transmitters
•Temperature Transmitters
•Level Transmitters
•Pressure Transmitters
•Strain Guage

14. Digital / Analog I/O’s
• Digital Inputs 1-4096 / more
• (Useful for sensing of entry of CAR)
• (To Sense COIN in vending machine)
• (To sense if Door Bell is pressed)
• Digital Outputs 1-4096 / more
• (To indicate Traffic Light Signals)
• (To display Alarm indication)
• (To display CAR is exiting parking)
• Analog Inputs 1-4096 or more
• (To continuously Scan the Temp.)
• (To continuously Scan Level / Flow)
• Analog Outputs 1-4096 / more
• (To control Temp. / Pressure / Level / Flow / Humidity etc. continuously.

15. Digital I/O Voltages
DC Input Modules
•24 V DC
•48 V DC
•10-60 V DC
•120 V DC
•230 V DC
•5-50 V DC Sink /Source
•5 V DC TTL Level
•5/12 V DC TTL Level
AC Input Modules
•24 V AC
•48 V AC
•120 V AC / Isolated
•240 V AC / Isolated
•24 V AC / DC
•Non-Voltage

16. Analog I/O Voltages
Voltage Range Decimal Equivalent
-10 V to + 10V - 32768 to + 32767
0 to + 10V 0 to + 32767
0 to +5V 0 to + 16384
1V to + 5V 3277 to + 16384
Current Range Decimal Equivalent
- 20mA to +20mA -16384 to +16384
0 to +20mA 0 to +16384
4 to +20mA 3277 to +16384

17. PLC Programming Languages
•Ladder Diagram Programming
•Function Block Diagram
•Sequential Function Chart
•Statement / Instruction List
•Structured Text

18. PLC Programming
[1] Edit / Write a Ladder Program
[2] Simulate Program using Simulator
[3] Change the Program if necessary
[4] Download the Program PC to PLC
[5] Execute the Program in PLC
[6] Change Inputs to see effects on Outputs
[7] Modify the Program for different field conditions & repeat steps 4,5,6.

19. PLC Applications using Static Application Panels
• CAR PARKING
• TRAFFIC LIGHT CONTROL
• SOFT DRINK DISPENSER
• WASHING MACHINE
• REACTION VESSEL
• PROCESS CONTROL
• TANK LEVEL CONTROL
• DOOR BELL DIGITAL LOCK
• MICROWAVE OVEN
• BOTTLING PLANT
• SEQUENTIAL CONTROL MOTORS
• SWITCHING OF LIGHTS
• MIXING OF 2 CHEMICALS
• STARER CONTROL
• STAR-DELTA STARTER

20. Other Applications of PLC’s
[1] Control of SPM’s
(Special Purpose Machines) – Like Drilling M/c or Grinding M/c or Lathes
etc.
[2] Packing Machines Like
Capsule Packing Machines Tablet Packing Machines;
Milk Pouches Packing M/c.
[3] Injection Moulding M/c’s
(Windsor Plastic Injection Moulding Machines) etc.

21. While Choosing PLC for an Application, following points
should be taken into consideration
• Maintenance
• Spare Parts
• Operation
• Modifications
• Losses (Production, Equipment, Personnel)
• Information Technology
• Space & Weight
• Flexibility
• Expandability
• Operability
• Cost of Control & Instrumentation

22. Aspects of Control & Instrumentation
• Standardization
• Speed of Response
• Hardware Variety
• Software Portability
• User Interface
• Memory
• Compactness
• Power Requirement
• System Integrity (Reliability, Availability, Security)
• Control & Logic Algorithms

23. A Control Unit Should have following capabilities as Standard
• Continuous Control
• Batch Control
• Logic
• Advanced Control
• Simulation
• Neural Network & Knowledge based Systems
• A PC-Oriented Programming Language
• Dual or Triple Redundancy
• High Scan rates (1 to 10 mS)
• High Resolution Time Stamping (1 mS)
• A Communication Processor that can handle popular protocols

24. Safety Considerations
•The most important safety feature, which is often neglected is PLC system
design. This feature must be included whenever a hardwired device is used
in order to ensure operator protection against the unwanted application of
power.
•Emergency STOP function should be completely hardwired.
Software functions should not be relied upon to shut-off the process or the
machine.

25. NOISE
•Electro-Magnetic Interference / NOISE / Unwanted Electrical Signals can
generate problems for all solid state circuits, particularly Micro-processors.
Each PLC manufacturer suggests methods for designing a noise-immune
system.
•I/O system are isolated from the field, but voltage spikes can still appear within
the low-voltage environment of the PLC if Proper Grounding practices are not
followed.
Often it is necessary to keep AC and DC wiring bundles apart, particularly
when high-voltage AC is used at the same time that low-level analog signals
are present.

26. Temperature Considerations
• Installing any solid state device requires paying attention to –
• Ambient Temperature
• Radiant Heat Bombardment
• And the Heat generated by
the Device itself.
• PLC’s are typically designed for operation over a broad range of
Temperatures, usually from 0 to 60 Deg.C
• For Cooling, blowing filtered air through the enclosure can resolve minor
difficulties.

27. Enclosures
• Enclosure of PLC protects PLC’s from moisture, Oil, Dust Particles and
unwanted tampering.
• Most Manufaturers recommend NEMA 12 Enclosure for the Standard
Industrial Environment.
• PLC’s are designed to be located close to the machine or the process
under control. This keeps the wiring runs short and aids in the trouble-
shooting procedure.
• It is not advisable to place a PLC near a Virating Machine, Electrical NOISE
Interference or Excessive Heat Environment conditions.

28. KEY-WORDS of PLC
• PLC Programmable Logic Controller
• PID Proportional + Integral + Derivative Control Function.
• DCS Distributed Control System
• SCADA Supervisory Control & Data Acquisition System
• RTOS Real Time Operating System

29. •RTC - Real Time Clock
•RTU – Remote Terminal Unit
•Timers – On-Delay
Off-Delay
Monoshot / Monostable
Pulse
Flasher
Astable
Bistable
•Counters – Up / Down
KEY-WORDS of PLC

30. • Flags / Registers / Latches / Memory Set-Reset / Retentive – Non-
Retentive
• HHT – Hand Held Terminal
• HHP – Hand Held Programmmer. It is used for PLC Programming at the
Installation site.
• MMI – Man-Machine Interface
• HMI – Human Machine Interface useful for ease of operation of PLC
by operator/s.
KEY-WORDS of PLC

31. H.H.T./ H.H.P.- Advantages
• Easy transfer of PLC Program to HHT / HHP for editing or troubleshooting.
• Easy transport of a program to the field to update a current machines
program.
• Rugged and industrially hardened for the factory environment.
• Low cost, cheaper than a notebook computer.
• Easy to use & easy to learn, no software required.
• Compact Size (pocket size)
• Easy storage of Program
• Monitor resident PLC Program for trouble shooting.

32. H.H.T./ H.H.P.– Disadvantages
• Not supported by some PLC’s.
• An HHP can hold only one program at a time – whereas a Laptop / PC
can hold many programs on its HDD.
• HHP’s usually require more keystrokes to enter and get the same
information as compared to a laptop / PC.
• Limited capability to display ladder rungs due to screen size
• Documentation not displayed
• Different HHPs are needed for different PLC manufacturers if more than 1
PLC’s are in field.
• If the Battery of the HHP discharges, a program stored in the memory will
be lost.

33. •Memory Cartridge / Module consists of either
RAM Random Access Memory.
(Volatile)
EPROM Erasable Programmable Read Only Memory.
EEPROM Electrically Erasable Programmable Read Only Memory.
FLASH Non-Volatile
KEY-WORDS of PLC

34. Softwired Vs Harwired components of PLC
• Soft-wired Components
Timers
Counters
Logic Circuits
Latches
• Hard-wired Components
24 V DC Lamps
Relays
Contactors
Solenoid Valves

35. Scan-Time / Scan-Cycle
•Scan Time of PLC
It is the time between an Input being sensed & the corresponding output.
•Single Scan Cycle
Single Scan Cycle function enables the circuit diagram to run for one
processing cycle and then stop.
This is useful in analyzing the circuit diagram and observing how it works.

36. PLC Scan
• Input Scan
PLC scans all Inputs
• Logic / Process Scan
PLC goes through the ladder program / logic
• Output Scan
PLC sends Outputs as per various Inputs and the corresponding
Ladder/Logic program.

37. Input Scan
•During the Input Scan the CPU scans each Input module for the ON / OFF
states of each of the associated input points.
•The ON / OFF input states are stored in the input status file.

38. Program Scan
• After the inputs are read and stored in the input status file, the processor will use
this information to solve the user ladder program.
• The processor scans the user program starting at rung zero at the left power rail,
working left to right and evaluating one instruction at a time until the output
instruction is reached.
• The Output status is the logical resultant of the solved input logic for that rung.
The logical one or zero output status is placed in the output status file.
• After completing rung zero, the processor goes on to rung 1,2,3… and so on,
sequentially, to the last rung except in case of Master Control Relay (MCR)
• At the end of the program, an END-Rung is automatically inserted which alerts
the CPU the it has reached the END of the Ladder Program.

39. PLC Concepts
• Forcing Inputs / Outputs
• RS232C / RS422 Ports
• Source-Sink Concept in PLC
• How to select a PLC for
a particular project ?
• PLC Types
Fixed / Modular

40. • Online (Run) / Offline Mode of operation.
• Uploading/ Downloading of Programs from PLC to PC & PC to PLC
• Display – LEDs / LCDs / VFD – Vacuum Florescent Display.
PLC Concepts

41. • MCR Master Control Relay Function
• File Handling / Addressing System
• PLC Simulator Software
PLC Concepts

42. Key-Words of PLC
• WDT Watch-Dog-Timer
In case of PLC control loss due to EMI / NOISE, WDT brings back control of
CPU to a Known State.
This Timer Circuit usually resides on the CPU card itself.
It works like a MONOSHOT PULSE GENERATOR of width greater than
MAXIMUM SCAN TIME.

43. WDT - Watch-Dog-Timer
• In order to insure system predictability a WDT is used to insure that the
processor completes each scan in a timely manner.
• WDT is a hardware timer incorporated into the CPU’s circuitry that monitors
the cyclical process / scan of the CPU.
• WDT is a safeguard that verifies the processor does not become stuck while
scanning the user program or for some other reason, become unable to
complete the current scan.

44. • The WDT is reset at the end os each Scan Cycle by the CPU when the
scan time is less than WDT’s preset time.
• In case of one or more sub-routines, program scan time can exceed WDT
time value. In some cases increasing the WDT’s preset value can solve
the problem.
• Some PLC’s have WDT with fixed time intervals, while others are
adjustable within specific limits.
• A typical default time of 100 / 200 ms is standard for many PLC’s with
either fixed or variable WDT Timing Cycles.
WDT - Watch-Dog-Timer

45. SLC-500 - Processor operating modes
• Program Mode
• Run Mode
• Remote Run Mode
• Remote Program Mode
• Test Mode
• Single-Step Test Mode
• Single – Scan Test Mode
• Continuous Scan Test Mode
• Test Mode – Test Program execution before allowing the PLC to operate the
actual Hardware.

46. GE – 90-70 CPU - Processor operating modes
• Run with Outputs Enabled
• Run with Outputs disabled
• Stop Mode
• Stop & I/O Scan Mode
• Run Mode Store Function.

47. • CCU - Central Control Unit It consists of a CPU + PALS-GALS + RTOS + EPROM
/ RAM / EEPROM
• Process / Ladder Logic Memory It could be integrated with CPU or in a
separate DATA / MEMORY CARTRIDGE / MODULE. Usually it is a replaceable
Cartridge.
• Optoisolation Analog I/O’s should be isolated otherwise induction / pickup
can lead to malfunctioning of PLC
Key-Words of PLC

48. Digital Electronics
• Boolean Algebra
• Binary / Hexadecimal nos.
• Logic Gates & Truth Tables
• AND
• OR
• NAND
• NOR
• Ex-OR
• Ex-NOR
• NOT

50. PLC Programming
AND
OR
NOT
NAND
NOR
Ex-OR
Ex-NOR
Timers
Astable
Monostable
Bistable
Counters
Flags
Retentive
Non-Reten
Registers
Retentive
Non-Reten
APPLICATIONS
Traffic Light Control
Process Control
Tank Level Control
Bottling Plant
Digital Lock
Microwave Oven
Washing Machine
Door Bell & Alarm
Sequential Control
Silo Control
Resistance Welding

51. Functioning of
Timers / Counters / Flags / Registers

52. DCS / SCADA
• D.C.S. Distributed Control Systems
• S.C.A.D.A Supervisory Control And Data Acquisition System. (Through
Network Data Acquisition, Data Display, Data Processing, Data
Storage, Data Analysis etc.)

53. DCS Vs SCADA
• Generally supplied by a single Vendor
with dedicated H/W & S/W.
• Costly due to redundent design
• Application Areas - Large Mfg. Facilities
• Comm’n - Confined to factory premises
(LAN for H/W)
• Analog Processing - Large Analog I/O’s
using PID’s
• Programming - by creating drawing like
charts called as configuration diagram
• Suppliers - Honeywell, Foxboro I/A series,
Bailey 90 etc.
• Normally supplied by Multiple / Competing
Vendors
• Competitive cost due to Multi-Vendor products.
• Can be applied to very low cost applications
• Comm’n - Can cover larger geographical area
by use of modems and T/p lines
• Small to medium Analog I/O’s with / without
PID.
• Programming - PLC by relay Ladder Diagram or
STL and SCADA using built-in graphics editor
and drivers.
• Suppliers - PLC’s - Siemens, Allen Bradley,
Omron etc. SCADA - Intellution, NI-Lookout /
Labview

54. Following Displays are available in most Control Systems
• Overview
• Area
• Group
• Details
• Trends
• Configuration
• Diagnostics
• Alarm Summary
• System Status (LAN)
• Scratch Pad

55. Solid State O/P Switching
•Advantages
[1] Fast Switching Speeds
[2] High Reliability & almost infinite life
[3] Low Power required to energize
[4] No Contact Arcing
[5] Little / nil Switching noise
[6] +ve switching, no contact bounce
[7] Can be hermetically sealed – good for hostile environments.
•Disadvantages
[1] May be destroyed by overload
[2] Tend to fail in ON state
[3] Heat dissipation
[4] Expensive to purchase
[5] Possibility of false trips from electrical noise.

56. Relay O/P Switching
Advantages
[1] Contacts forgiving to a temporary overload
[2] Immune to false trips from elec noise
[3] Little voltage drop across contacts
[4] No restrictions when connecting in series or parallel configurations
[5] Difinite ON / OFF state, with contacts physically open.
[6] No Leakage
[7] Contacts generate little heat
[8] Inexpensive to purchase
Disadvantages
[1] Mechanical switching is slow
[2] Mechnical life is limited by demands of the load and the contacts.
[3] Require 50mA or more to energize
[4] Subject to contact arcing or welding
[5] Subject to contact bounce
[6] Cannot be completely sealed.

57. • UCP - Unified Control Panel
• UCS - Unified Control System
• UCN - Universal Control Network
• UOC - Unit Operation Controller
• TDC - Totally Distributed Control System
• SOE - Sequence Of Events
• SP - Set-Point
• SFC - Sequential Function Chart
• SAT - Site Acceptance Test
• SAS - Safety & Automation Systems
Other Terms Used in Control Systems

58. RTU - Remote Terminal Unit
ROC - Rate of Change
PV --- Process Variable
PS --- Process Station
PSD - Process Shut-Down
PIU - Plant Interface Unit
PIN - Plant Interface Network
PCS - Process Control System
PFD - Process Flow Diagram
PCN - Process Control Network
P&ID - Piping & Instru’t Diag.
Other Terms Used in Control Systems

59. OBT - Optical Bus Terminal
OLE - Object Linking & Embedding
OLM - Optical Link Module
NIU - Network Interface Unit
MC - Multifunction Controller
MTU - Master Terminal Unit
MCS - Master Control Station
MAS - Manufacturing Automation System
MAP - Manufacturing Automation Protocol
MTBF - Mean Time Between Failure
MTTR - Mean Time To Repair
Other Terms Used in Control Systems

60. • LLPIU - Low-Level Process Control Station
• LCN --- Local Control Network
• LCR --- Local Control Room
• LAN --- Local Area Network
• ISA - Instrument Society of America
• ISO - International Standards Organization
• HSE - High Speed Ethernet
• HIPPS - High Level Process Protection System
• HAZOP - Hazard & Operability Study
Other Terms Used in Control Systems

61. • FAT- Factory Acceptance Test
• EUC - Equipment Under Control
• ESD - Emergency Shut-Down System
• EC --- Extended Controller
• DPS - Dynamic Positioning System
• AC --- Adaptive Control
• CFC - Continuous Function Chart
• C & I - Control & Instrumentation
• CCR -- Central Control Room
Other Terms Used in Control Systems

62. Other Terms Used in Control Systems
•BCL -- Batch Control Language
•BC --- Basic Controller
•AEC - Advanced Extended Controller
•AMC - Advanced Multifunc’n Controller
•CAD - Computer Aided Design
•CADAS - Computer Aided Design Analysis & Application

63. FF-Bus -Foundation Field Bus
• FF-Bus is a Digital Common System
• A Summary of improvements, which FF-Bus will offer as it becomes
more widely applied are
• Higher Communication Speed - 10 to 100 M Baud
• Higher nos. of modes per branch to reduce caballing & termination effort
• More efficient Communication
• Better diagnostics & predictive maintenance in field Instrumentation.

64. • More reliable Control System because of better maintenance & Higher
distribution control.
• Faster Control System Response.
• Saving in Hardware (Cabling, I/O cards, Cabinets)
• Higher Accuracy because Process Parameters are Sampled Locally &
Transmitted Digitally to local / remote Control Units.
• Major Improvements in System Commissioning saving Time & Costs.
FF-Bus

65. FF-Bus
• Reduction in Documentation (No. of Loop Diagrams, Termination Schedules
etc.)
• Possibilities od using Multifunction Instruments - Where one Transmitter
measures multiple variables (e.g. A Corolis meter can measure - flow,
Density & Temperature )
• A High Degree of Inter-operability among system Computers & Instruments
from different Vendors.

66. • DPS - Dynamic Positioning System
• Availability = MTBF / (MTBF + MTTR)
Categories of Consequences Definitions
• Catastrophic ---- Multiple Loss of Life
• Critical -------- Loss of a Single Life
• Marginal ------- Major injuries to one or more persons.
• Negligible ------ Minor injuries at worst

67. Categories of Likelihood
Categories
of Likelihood
Definition
(in System Life)
Failures
Per Year
Frequent Many Times > 10-3
Probable Several Times 10-4 to 10-3
Occasion
al
One Time 10-5 to 10-4
Remote Unlikely 10-6 to 10-5
Impossible Very
Unlikely
10-7 to 10-6
Incredible Cannot
believe it
could happen
< 10-7

68. Analog Input
DC models of Pico are provided with two analog inputs I7 and I8. The
permissible input voltages are between 0 V and 10 V. The measured data is
evaluated by an integrated Analog Value Comparator relay.
Circuit Connection
Each line in the circuit diagram display is a circuit connection.

69. Circuit Diagram Elements
The circuit diagram is made up of circuit diagram elements from
conventional wiring practice. These include input, output and auxiliary relays
as well as function relays and P buttons.
Contact/Coil Monitor
The Contact/Coil Monitor is a dialog for displaying and forcing the logic
states of selected relays (contacts / coils).

70. Device Test
The device test shows in plain text the results of comparison between the
selected Pico device and the circuit diagram. All contact/coil elements that
are not available on the device used will be listed, and the number of circuit
connections used will be checked. If the Pico device cannot properly process
the circuit diagram, a device will be suggested on which the circuit diagram
can be used successfully.

71. Function Relay
Function relays are used for complex switching tasks. Pico devices are
provided with the following function relays: Timing relays (T), Time switches (H),
Counters (C), Analog value comparators (A), Text relays (D).
Impulse Relay
An impulse relay is one that changes and then retains this state if a voltage is
momentarily applied to it.

72. Input
External contacts are connected to the inputs of the device. Inputs are
evaluated in the circuit diagram via the switching contacts I1 to I12 and R1 to
R12. The 24 V DC Pico models can also receive additional analog data via
inputs I7 and I8.
Input Debounce
Input signals can be evaluated by the device with a delay in order to
compensate for the contact bounce of switches and pushbuttons.

73. Interface
The device interface allows circuit diagrams to be exchanged and stored on a
memory card or PC. A memory card saves both the circuit diagram and
device settings. PicoSoft PC software allows you to control the device from the
PC. The PC is connected to Pico via the "1760-CBL-PM02" cable.

74. I/Q Window
The I/Q window contains the input simulator and the display for Q and S coils.
The input simulator or I window is used as a central tool in circuit diagram
simulation. It enables you to create dynamic input signal states for the
simulated circuit diagram. For this you can also assign different functions to
the I and R buttons.

75. I/R Function
The I/R Function determines the switching function of the elements I1 to I16
and R1 to R16. These can be latching make contacts, latching break contacts,
momentary make contacts or momentary break contacts.

76. Operator Buttons
The device features 8 operator buttons by which you can select the menu
functions and also enter the circuit diagram directly via the Pico display. The
centrally arranged cursor buttons are used to move the cursor in the Pico
display. DEL, ALT, ESC and OK are also provided with additional functions.

77. Output
The outputs are used to switch loads such as contactors, lamps or motors. The
outputs are controlled in the circuit diagram via the output relay coils Q1 to
Q8 and S1 to S8.
Parameters
Function relays are assigned particular parameters by the user. Set values
may include, for example, switching times or counter set points. These are set
in the Contact/Coil dialog.

78. P Buttons
The P buttons allow you four additional inputs that are switched via the
cursor buttons on Pico instead of external contacts. The switching
contacts of the P buttons are wired in the circuit diagram.

79. Retention
This function allows data to be retained in the device even after its power
supply has been switched off. Retentive data consists of: Device circuit
diagram, parameters, setpoints, text, system settings, password, actual values
of auxiliary relays (markers), timing relays, counters.

80. Signal Diagram
The Signal Diagram allows you to display the behavior up to eight selected
relays along a time axis. The diagram produced can also be printed out for
documentation purposes.
Single Cycle
The Single Cycle function enables your circuit diagram to run for one
processing cycle and then stop. This helps you in analyzing the circuit
diagram and observing how it works. This function is only available during
Simulation.

81. Startup Behavior
The startup behavior is an important help during commissioning. The circuit
diagram may not be completely wired when it is transferred to Pico, or the
system/machine to be controlled is in a state in which it cannot be controlled
by Pico. If Pico is then switched on, it may therefore be desirable for the
outputs to remain inactive. For this set the startup behavior to STOP. If the
startup behavior is set to RUN, Pico will start processing the circuit diagram as
soon as it is switched on.

82. Stop Point
In order to analyze your circuit diagram effectively, you need a tool to
interrupt processing selectively, evaluate the state of selected contacts or
coils and continue processing. The Stop Point function makes this possible. It is
only available during Simulation.

83. Wiring via the Keyboard
Pico Soft also enables you to wire up your circuit diagram via keyboard
commands.
Selecting Make/Break Contact Behavior
Entering letters in lower case selects make contacts, and entering letters in
upper case selects break contacts.

84. Adding / Deleting Contacts
Position the cursor on the contact field required and enter the contact via
the keyboard. Use the following shortcuts for contacts & f’n relays:
i, I Controller Inputs
p, P Soft Inputs - Keypad
q, Q Controller Outputs
m, M Internal Marker Bits
c, C Counters
t, T Timers
h, H Time Switch Relay
a, A Analog Set point Compare
d, D Text Display
r, R Expansion Inputs
s, S Expansion Outputs or Internal Marker Bits To delete the contact, press
the Del key

85. Adding / Deleting Coils
Position the cursor on the coil field required and enter the coil via the
keyboard. Use the following shortcuts for coils and coil functions:
q Controller Outputs
m Internal Marker Bits
t Timer "Trigger" coil
c Counter "Trigger" coil
d Text Display "contactor" function
s Internal Marker "contactor" function

86. To select the coil function required, press the Shift key and select the
appropriate coil function letter below:
Shift + E Impulse relay
Shift + S Latching (Set)
Shift + R Unlatching (Reset)
Shift + D Direction coil for counter
The default setting is for the contactor function. To revert to the simple
contactor function of the coil, press the letter for the coil concerned.

87. To delete the coil,
press the Del key.
Connecting Inputs and Outputs
Use Shift+Cursor key to make the connection between the individual
contacts and coils.
Adding Empty Lines
Position the cursor on the circuit connection in front of which you wish to
add the empty circuit connection. Press Ctrl+I to add the empty circuit
connection.

88. Deleting Circuit Connections
Position the cursor on the circuit connection you wish to delete. Press Ctrl+D to
delete the entire circuit connection.
Deleting Connections
Position the cursor on the connection you wish to delete.
To delete the connection,
press the Del key.
If the circuit connection contains branches, the selected connection will only
be deleted up to the next node.

89. Skillcruise.com