Documenting skills is value-add 

ISA certification provides an objective, third-party assessment, and confirmation of a person's skills.  It gives manufacturing and factory staff the opportunity to differentiate themselves from their peers and gain recognition. InTech covers three certification areas in its monthly Certification department.

ISA Certified Automation Professional (CAP) program

Certified Automation Professionals (CAPs) are responsible for the direction, design, and deployment of systems and equipment for manufacturing and control systems.

The following questions come from the CAP study guide, Performance Domain V, Deployment.

Field installation and checkout and startup of the systems

CAP questions

1. If an exothermic reactor can run-away in manual, then the temperature controller should be tuned with a(n):

A. Open loop short cut method  
B. Closed loop  
C. Lambda Tuning method  
D. Reaction curve method  

2.  An increase in which setting can compensate for a thermowell lag time?  

A. Rate time  
B. Reset time  
C. Gain  
D. Filter time

CAP answers

1.  The best answer is B, closed loop.

The controller must stay in automatic to prevent a runaway reaction. Closed-loop methods keep the controller in automatic. Normally, we maximize the gain to the point where either the error is small enough or the process starts to show a slight oscillation. It does not imply the ultimate oscillation method. The controller is in manual for open loop, Lambda Tuning, and reaction curve methods.

Reference: McMillan, Good Tuning: A Pocket Guide, ISA Press, 2000.  

2. The correct answer is A, rate time.

Thermowell and temperature processes have multiple interacting thermal lags. Rate time cancels a secondary thermal lag that can improve control in a slow temperature process without A/D chatter. Reset time adds another lag that further increases the apparent dead time from multiple lags. A large thermowell lag reduces the allowable gain. A process variable filter adds another lag that further increases the apparent dead time from multiple lags.

Reference: McMillan, Good Tuning: A Pocket Guide, ISA Press, 2000.

For information about the CAP program, go to http://www.isa.org/CAP.

ISA Certified Control Systems Technician (CCST) program

 Documenting1

Certified Control System Technicians (CCSTs) calibrate, document, troubleshoot, and repair/replace instrumentation for systems that measure and control level, temperature, pressure, flow, and other process variables.

These questions comes from the Level I study guide, Domain 3, Troubleshooting. Level I represents a professional who has a five-year total of education, training, and/or experience.  

CCST questions

1. A low resistance reading from an ungrounded signal lead connected to a ground indicates a problem of:

A. A lead having an unwanted   connection to ground  
B. An open circuit from the lead to   ground   
C.  An open circuit from the lead to   the casing  
D.  None of the above 

2. What kind of wires in a process control loop would most likely be shielded cables?  

A. Power wires  
B. Ground wires  
C. Signal wires  
D. Control wires

CCST answers

The correct answers are A for question number one and C for question number two.

Potential is the difference in voltage between two points. One of the points should be a ground with voltage equal to 0 (zero). The best way to avert the ground loop in this question is to ground the shield at only one end of the circuit. The correct answer is B. 

For information about the CCST program, go to www.isa.org/ccst.


ISA Certified Industrial Maintenance Mechanic (CIMM) program


Certified Industrial Maintenance Mechanics (CIMMs) are responsible for preventive, predictive, and corrective maintenance. They are multi-skilled individuals whose expertise is primarily mechanical in nature as opposed to instrumentation or electrical.

CIMMs have a minimum of five years of relevant work experience in the maintenance mechanic field or three years experience and a two-year associate degree in maintenance or a related field.

These questions are from Performance Domain I: Maintenance practices.

CIMM questions

1. Prior to operating a powered industrial lift truck in the plant, each operator must successfully complete:

A. An approved training program  
B. The accompanying work order  
C. All non-essential maintenance tasks first
D. A hot work permit 

2.  Selecting a ladder of sufficient length is important in order to avoid:

A. Door openings
B. Unnecessary climbing
C. Electric power lines  
D. Stretching or reaching

CIMM answers

1. The correct answer is A, an approved training program.

OSHA requires all operators of powered industrial lift trucks undergo classroom and field-testing. Because of the hazards presented by the elevated loads while in motion, it is imperative operators fully understand how properly to handle equipment and loads. The operator must also demonstrate the ability to properly inspect and operate powered industrial lift trucks before receiving his or her certificate. 

Reference:IBEW-NECA, OSHA Requirements for General Industry, IBEW-NECA, 2003. 

2.  D, stretching or reaching, is the correct answer.

A ladder will easily tip over if you reach outside the centerline.

Reference: Hagan, Accident Prevention Manual for Industrial Operations, National Safety Council, 2001.  

Nicholas Sheble (nsheble@isa.org) edits the Certification