Jason K. Firth, C.E.T.

Instrumentation, Control, and Automation

The path of the Journeyman Instrument Technician

Dec 132014

December 13, 2014

I'm Jason Firth.

 

A few days ago, I wrote about some examples of situations where using unqualified instrument techs caused catastrophic damage and the potential for a massive loss of life.

Today, I'm going to talk a bit about one of the paths a person can take to become a qualified instrument technician.

Centuries ago in Europe, there existed a system of guilds. These were organizations that controlled different skilled crafts and trades. They served two purposes: First, they served the public by ensuring that if a person was doing a trade, they had trained under different master craftsmen and had met a certain level of skill. Second, they served themselves by creating a monopoly in that craft or trade, which allowed them to charge more.

A person who wanted to enter a certain craft or trade would train as an apprentice under a master craftsman without charging a fee for their work, until that person had spent enough time working with their master, after which they would be released from their obligation, and they would become a Journeyman. In the German tradition, a Journeyman would then don the traditional garment, a black suit with a wide brimmed hat, and travel from master to master, learning the trade.

I want to spend a bit more time on this idea, because I find a lot of the aspects of it romantic. Some other journeyman traditions were that a Journeyman would wear a gold earring, to pay the gravedigger if they died. A journeyman would start their journey with 5 gold pieces, and after their journey was complete, they would have the same 5 gold pieces, to signify that the journey was not to become rich, but to learn their trade or craft. About half way through their journey (in terms of years), they would settle in with a master, and a few years after that, they'd begin work on the piece they would present to the guild; their masterpiece. This masterpiece would be the final test that convinces the guild that the journeyman is ready to become a master themselves. At that point, as a master tradesman or craftsman recognised by the guild, they could open their own shop in a town.

Today, some vestiges of that time still exist, but the guilds of antiquity are long disbanded.

Today, apprenticeship programs in Canada are managed by the provinces, each having its own legislation authorising the existence of such programs and describing how the program shall be administered. In addition, the 1994 Agreement on Internal Trade includes provisions for the “Red Seal” program, which allows a journeyman to travel anywhere in the country and maintain their certification freely and automatically.

Because each program is administered by a different body, there are differences in how each program is run, and the terminology used. The two most popular names are "Industrial Instrument Mechanic" and "Instrumentation and Control Technician", although Alberta and the Northwest Territories call the certification "Instrument Technician", and Saskatchewan and Nunavut call their certification "Industrial Instrument Technician".

In most provinces, there are two paths to becoming a journeyman instrument tech.

The first path is called “apprenticeship”. In this path, a worker with no previous experience is hired as an apprentice. This person will learn from and assist the journeymen for 4-5 years. During the process, the journeymen will sign off that an apprentice has reached proficiency with a certain task, out of hundreds included in a book provided to the apprentice. Every year, there is a trade school the apprentice must attend for 10 weeks. The apprentice is often laid off for these 10 weeks, and won't have their normal income during trade school. At the end of these 5 years, the apprentice must write a final trade exam. Depending on the jurisdiction, there can be multiple trade exams: One provincial, and one inter-provincial. (more on this later)

Although theoretically a person off the street may be hired for an apprenticeship, hiring a person for an apprenticeship is a gamble for the company. A company hiring an apprentice risks having spent time and money training an apprentice without getting a journeyman at the end, so they'll hedge their bets. One way they'll do that is hiring a person who already has shown a proficiency with instrumentation, by successfully completing an engineering technician or engineering technology program. Other times, a particularly bright operator at a union plant may get the first shot at an apprenticeship. It's also common for journeyman electricians to apprentice as an instrument technician, since some of the skill sets align.

The second path is called “trade qualification”. In this path, a worker gets hired as an instrument tech through their education (an engineering technology diploma meets the academic requirements) and experience, and works alongside journeymen for 4-5 years. They must get their skill sets signed off by their supervisor. After working for 4-5 years and achieving the appropriate competencies, that person can write the trade exams the same way an apprentice can, and will be granted a full journeyman certification if they pass.

Occasionally, people use the term “interprovincial” and “provincial” with respect to their journeyman certification. Things vary between provinces, but generally there are different standards one must meet to achieve the provincial certification versus the interprovincial certification. In Alberta, for instance, an apprentice writes their provincial test first, then must write the interprovincial test later. In Ontario, for a long time, a person who got one score on their interprovincial exam (say, a 60%) was granted a provincial certification, but if they got another score (say, a 70%), they were granted an interprovincial certification.

There's a variety of different categories of skills that an instrument tech must have to achieve journeyman certification.

Common Occupational Skills

Understanding of legislation and workplace standards in the workplace, including, but not limited to worker safety legislation, WHIMIS, PPE and lockout/tagout.

Process Measuring And Indicating Devices

There's a huge number of instruments out there that a journeyman must understand and be capable of installing, maintaining, and troubleshooting. In addition, there are certain documentation and calibration standards which must be met to consider a calibration or validation valid, and certain tools a journeyman must have to assist in troubleshooting. When comparing similar trades, it's this scope that differentiates the instrument tech while working on instrumentation.

Safety And Security Systems And Devices

There's a huge number of safety related instruments out there that a journeyman must understand and be capable of installing, maintaining, and troubleshooting. In addition, there are certain documentation and calibration standards which must be met to consider a calibration or validation valid, and certain tools a journeyman must have to assist in troubleshooting.

Hydraulic, Pneumatic And Electrical Systems

One class that every instrument tech must take in trade school that no electrician will need to take is fluid mechanics. There are certain theories that must be understood for hydraulic and pneumatic systems to make sense. Pneumatics in particular may be a huge element of instrumentation -- You might have an entire plant running on pneumatic controls, and an instrument tech must be capable of working on all of it. In addition, there's the need to know electrical and electronic systems.

Final Control Devices

All the measurement in the world is meaningless if you can't control something with that measurement. Instrument techs must intimately understand valves, actuators, positioners, variable speed drives, and all the various components that connecting them together. Fail safety is a critical part of this.

Communication Systems And Devices

Communication is a growing facet of instrumentation. Techs today need to understand control network systems and devices, signal converters, gateways, bridges, switches, and media converters. Recently the ISA asked: "Is instrumentation evolving into IT?". I don't think it is, because of all the other things that are involved, but the question is relevant considering the increased knowledge of IT required.

Control Systems And Process Control

This covers a wide scope, from discrete PID controllers, to PLCs, PACs and DCSes, to loop modelling and control fundamentals. There's a number of different tools an instrument tech needs to understand, from feed forward and cascade loops, to ratio loops, to the different standards for tagging and description to ensure the next guy understands what you've set up.

There's a lot to learn, and with all these areas of expertise comes a huge responsibility.

 

Thanks for reading!

Trade National Occupational Analysis - Instrumentation and Controls Technician

Possibly Apocryphal

Dec 102014

December 10, 2014

I'm Jason Firth.

 

A quote attributed to Mark Twain goes "History never repeats itself but it rhymes".

I started my career going to college as an instrumentation engineering technologist. Over 20 years before that, my father was going to trade school as an instrument mechanic just a couple hundred kilometers away in Brandon.

Instrumentation is a fast moving trade: New computer control products are constantly coming out, there's new technologies, new devices, new trains of thought, and tomes filled with the new ideas in control that come out every month. However, a lot of the fundamentals stay the same. A lot of the curriculum we both learned could be taught in either classroom. Pneumatics, electronics, fluid mechanics, op-amps, PID controllers, final control elements.

There's one story in particular that both of us were taught, 20 years apart. It's a story about why you should have qualified people working as instrument techs.

I'll start with the process, and move on from there.

The Kraft paper making process starts with wood chips, which are then placed in a "digester". A powerful caustic called "white liquor" is added to the digester, and the whole unit is heated and put under pressure. The white liquor dissolves the stuff keeping the wood fibres bound together, and once the digesting process is complete, you've got a combination of wood pulp, and spent white liquor, which is called "black liquor", because it becomes filled with all the sugars and lignates and such from the wood. From the digesters, the result is placed on a giant drum called a washer, and the black liquor is washed out of the fiber, which then heads off to your paper machine or pulp machine or whatever you're going to use the fiber for. The black liquor then pumped to the recovery process.

The recovery process takes that black liquor and "recovers" it into white liquor. The first step is that the black liquor is pumped into a giant boiler (we're talking 8-10 stories tall, with a cross-section of a small house), called a "Recovery boiler", where it burns. The sugars and lignates from the wood burn, producing heat. Once the liquor is burned, it drops into a chamber below the boiler, at which point it is now "green liquor". From there, it gets sent to the recausticizing plant, where it is clarified and strengthened, and it becomes white liquor once again.

Recovery boilers are huge, as we've established, and they're also quite high pressure. Plants I've worked at had steam of 800psi, but I've heard of plants as high as 1500psi. Besides producing enough steam to run the process, there is often enough steam left over to run a turbogenerator to offset the huge amount of electricity involved in the paper making process. I've seen turbogenerators of 20MW, but 100MW or more of electricity generating capacity is definitely out there. That's enough energy to power a small city. When paper prices collapsed, some plants remained operational only from profits made by selling electricity back to the grid!

So you have these boilers that are dangerous by themselves simply by virtue of being massive pressure vessels containing enough energy to power a small city, but recovery boilers have an additional danger: The caustic which drops into the chamber below the boiler is called "slag", and it reacts violently with water. Getting water into your recovery boiler is a great way to not have a recovery boiler any longer.

So finally, on with the story. Fort Frances is a town in northwestern Ontario, which for a long time had a pulp & paper mill. In recent years the mill has come on hard times, but before that it was in operation for decades.

The story goes, that on two separate occasions, they literally blew up their recovery boiler, because they weren't using qualified people to handle their instrumentation and controls.

The first story goes like this: The union plant allowed someone from operations to work as an instrument technician without going through an apprenticeship first. One day, they installed a fail open control valve on the fuel line into the boiler. The first time the valve lost air pressure, the fuel valve opened 100%. The huge excess of fuel caused a boiler explosion. Fail safety is one of the fundamentals of instrumentation, so any qualified instrument tech should have caught the problem before it became a problem.

The second story goes like this: Apparently not learning from their first episode, the plant allowed someone who wasn't qualified as an instrument technician to work as one. One day, the boiler was running dry to do some testing. This is an extremely unusual situation, and generally it isn't something you'd ever do, because you can damage the boiler. No tag out was employed to explain that the boiler was being run dry intentionally, so when an operator noticed the low boiler water level, they panicked and started adding water. When you add cold water to a superheated empty boiler, the water immediately boils, turning to steam. The shock can cause an explosion. They ended up blowing up their boiler again. Lock out and Tag out are another one of the fundamentals of instrumentation, so any qualified instrument tech should have tagged the controller, preventing the problem.

In the age of the Internet, I haven't been able to find any articles supporting the idea that either of these things happened. However, 20 years apart, at two different colleges, in two different programs, the same stories were told about the same mill in Northern Ontario, in both cases a cautionary tale of using unqualified instrument techs.

Thanks for reading!