Mechatronics Certification Tests

Mechatronics Certification Test - Programmable Logic Controllers (PLCs) 2

This test covers advanced principles and applications of programmable logic controllers (PLCs).   Among the advanced topics are PLC real time considerations, various levels of PLC networking, alternate programming languages for PLCs, international standards applied to PLCs, integration of logic and motion control in PLCs, integration of process control in PLCs, advanced human / machine interface (HMI) for PLCs, supervisory control and data acquisition (SCADA) with PLCs, alarm management, batch control, power failure strategies, and process safety.

This certification test is aimed at entry level technicians who may be involved in the assembly, test, startup, troubleshooting, maintenance, repair or upgrade of basic packaging machinery modules.

Price:
$125.00
Test Topics & Questions
  • Describe methods of insuring machine and operator safety in the event of a PLC failure.
  • Describe methods of insuring machine and operator safety in the event of a power failure and upon resumption of power.
  • Describe methods of insuring machine and operator safety in the event of an unexpected loss of some or all input signals or output responses.
  • Describe the safety implications of using the force function of a PLC
  • Describe the use of a master control relay for de-energizing actuators in a PLC system
  • Describe the characteristics of fail-safe hard wire circuitry required for safety (for example, stop buttons should be normally closed)
  • Describe the use of LOTO (lockout/tagout)
  • Describe the safety procedures of a NFPA 70E (arc flash) related to category 0 to category 4 working on a PLC within an enclosure with mixed voltages above 50 volts
  • Interpret NFPA79 and IEC symbols and schematic diagrams for PLC systems
  • Describe when and how input and output cards may be replaced under power and during operation
  • Describe special inputs, outputs and instructions that are designed to improve throughput response.
  • Describe the impact of leakage currents and loading on PLC inputs and outputs.
  • Demonstrate the ability to design and implement circuits to interface electronic devices with sinking and sourcing inputs and outputs
  • Describe the function of I/O configuration
  • Properly install an analog input module and analog output module
  • Identify when to use remote I/O
  • Describe the methods for troubleshooting remote I/O
  • Describe the methods of troubleshooting various device networks (blinking lights, check for indicator lights, functioning cable, etc.)
  • Understand the different components of various device networks
  • Describe various industrial networks and give an application (FieldBus, DeviceNet, Ethernet/IP, ControlNet, Modbus TCP, EtherCAT)
  • Describe the method for troubleshooting loose terminal connections
  • Describe the method for troubleshooting output module malfunctions (blown fuse)
  • Describe the safety and programming between normally opened or normally closed device output
  • Create and operate a program to measure processor scan time 
  • Create and operate a system to measure system throughput
  • Compare the advantages and disadvantages of AC and DC I/O.
  • Explain how various processing tasks affect throughput.
  • Explain how input and output response time affects control of a machine or process
  • Describe characteristics of the IEC61131-3 programming languages (LD, ST, FBD, SFC, CFC)
  • Describe the function of an address tag
  • Describe the importance of program file management and backups
  • Describe the function of an array and give an application
  • Explain different ways to use PLC to troubleshoot your machine (other than discrete)
  • Describe logic flow and process (including racing conditions, left-to-right, top-to-bottom, asynchronous I/O)
  • Describe the use of a shift register in a PLC
  • Describe the use of a sequencer in a PLC
  • Describe the use of an edge-triggered instruction (one-shot) in a PLC
  • Describe the use of a debounce programming technique in a PLC input
  • Describe the techniques of initial assessment for troubleshooting a PLC system
  • Describe the use of various numbering systems, including binary, BCD, octal, hexidecimal, decimal
  • Demonstrate the ability to convert between various data types (integer, double integer, ASCII, floating point, real)
  • Describe the significance and limitations of memory configuration (fixed, configurable, definable)
  • Define the function of the Programmable Organizational Unit (POU) (routine)
  • Identify the importance of program source control (file management)
  • Describe the function of the PLC operations using program control and subroutines
  • Describe the operation of the program flow control instructions (skip, jump, label, resume, return, etc.)
  • Describe the function of an action (subroutine)
  • Describe two types of files for storing numeric data and give an application of each (integer file, floating point file, etc.)
  • Describe the function of PLC math instructions and give an application (ADD, SUB, MUL, DIV)
  • Describe the function of PLC compare instructions and give an application (>,<,=)
  • Describe the operation of the move instruction
  • Describe how to use a mask to modify data
  • Provide an example of advanced math functions (trig, exponents)
  • Describe methods of sending and receiving data communication (including messaging and publish/subscribe)
  • Describe the purpose of function blocks (reusable code)
  • Describe the conditions needed for proper math operations (example: divide by zero)
  • Describe how to convert between sensor input and output units given sensitivity
  • Calculate the resolution of an analog output module
  • Describe the function of analog input and output scaling and give an application
  • Describe the function of analog input and output resolution and give an application
  • Describe the function of analog input and output accuracy and give an application
  • Describe the function of analog input and output repeatability and give an application
  • Describe how to determine that an analog input or output module is functioning properly 
  • Describe the analog signal types (+/- 10 VDC, 4-20 mA, mV, TC, RTD, etc.)
  • Describe the effects of noise on an analog signal
  • Calculate sensor sensitivity given measurement data
  • Describe the function of an HMI and give an application
  • Describe how to connect an HMI to a PLC using RS232/RS485
  • Describe the transfer of the data types between HMI and PLC
  • Describe various types of screen objects
  • Identify dynamic screen objects
  • Describe the difference between momentary and maintained buttons
  • Describe the function of alarm history
  • Describe methods of troubleshooting screen objects (including stuck button)
  • Describe the function of HMI software documentation and give an application (backups, archiving)
  • Describe the functions of three types of output objects
  • Describe how to create and format a Text object
  • Describe how to create and configure a Screen Selector object
  • Describe the differences between device, cell, enterprise networks
  • Demonstrate a basic understanding of networking terminology (including bus, switches, devices, router)
  • Describe the function of a communications driver
  • Describe the function and basic operation of serial communication and give an example
  • Describe how to setup a serial communications driver (including baud, stop, parity)
  • Describe safe operating practices to prevent security safeguarding issues (including check w/ local IT dept., cyber security)
  • Describe the importance of assigning proper IP addresses
  • Describe how to configure an IP address on the computer (subnet mask, gateway)
  • Demonstrate an understanding of different network protocols
  • Describe the application of PLC’s and HMI’s in one-to-one, one-to-many, many-to-one, and many-to-many configurations
  • Describe when a Ethernet cross-over cable or null modem cable may be required
  • Describe the methods of troubleshooting a loss of data communications (check cables, LEDs, ping, reboot)
  • Describe open v. closed loop systems (beyond motion)
  • Describe techniques for troubleshooting a closed loop system
  • Describe the operation of a PID control loop within a PLC
  • Describe the components required to implement PID (required hardware/software)
  • Describe the use of a PLC for temperature control using a PID loop
  • Describe the difference between a process variable and a control variable
  • Identify the different architectures for motion control systems
  • Identify the differences between an analog, digital, network, or pulse train interface (between PLC and drive)
  • Describe the difference between incremental and absolute encoders and the implications on homing
  • Describe the function of the PLC in a SCADA (supervisory control and data acquisition) system
  • Who should take this test?

    Individuals who have experience working with PLCs on packaging equipment.  Also, students who have completed the course work the competencies cover on the test. 

  • How long does it take to complete the test?

    Approximately 2 ¾ Hours

  • From the time of purchase, how long do I have to take the test?

    You must complete your test within 6 months of completing your purchase. After 6 months, you will no longer have access to your test. 

  • How many times can I attempt the test?

    You will have only one attempt at passing the test per purchase.