The 2011 IEC National Apprentice of the Year competition concluded with me placing second, building the Rocky Mountain IEC’s winning streak to two straight years following last year’s second place finish by Ray Shorkey.  Congratulations to Zeb Upton of IEC Fort Worth for winning first place and James Huggins of IEC Florida West Coast for rounding-out the top three in third place.  A big thank you to Home Depot for the cash prize and to the other companies who included prizes:  Klein, Ideal, Greenlee, Bosch, 3M, Ty-Rap, American Technical Publishers (ATP), and any others that I am missing.  A huge thank you to all those at IEC who put together and staffed the competition as well as the staff at the Rocky Mountain IEC who made the trip and competition possible for me to attend, especially to Jake Jackson who supported me in the months prior to and during the competition.  A special thanks to the Livewires who donated $50 to each of this year’s 26 contestants. Lastly, a thank you to Home Depot and Schneider Electric for sponsoring the competition.

The competition was very intense.  All of the contestants earned the right to be there.  We all competed with the constant knowledge that one mistake is all it would take to eliminate the opportunity to win due to everyone’s level of skill.  I have never felt that much pressure in my life – the journeyman test is going to be a walk in the park after this experience.  My nerves were fairly frazzled at the end of each day, and from speaking with other contestants, I do not think anyone got a good night’s sleep.  The contest was as follows:

• Tuesday:  100 Question Written Test, 2.5 hours
• Wednesday:  Ladder Diagram Word Problem, 30 minutes
• Wednesday:  Control Circuit Wiring, 5 hours
• Thursday:  Conduit Bending, 30 minutes (or 45 minutes, I can’t remember)
• Thursday:  Troubleshooting, not timed, but took about 30 minutes total

The experience was great.  I had the opportunity to meet some of the other contestants, company representatives at the trade show, and IEC national staff.  Meeting other local business executives and owners who are on the board of the Rocky Mountain IEC was my highlight of the week:  Wade Hamlin of N Line Electric; Curtis Miller and Brian Ream of CDM Electric; Janet Martin of Bret’s Electric; and Scot Schultz of Allcable.  A thank you to them for making me feel welcome.

When I returned home, the company for whom I work, Encore Electric, invited me in to the office to show me an area where they put my regional wire-off trophy, a banner stating congratulations for 2nd place at the national competition, and a place on the wall for my national trophy.  I was congratulated by a couple of the owners and many of the company’s superintendents.

What’s next?  I will begin writing more articles here in the hopes that I can one day work up to writing an article with enough quality to be published.  I also put in my application for my journeyman license last Friday.  I will test as soon as I receive the approval letter in the mail.  I will be furthering my teaching career by continuing to work towards instructor positions at both IEC and RRCC.  I will always be improving my general work skills with classes and books, such as the PLC 3 class I will be taking next semester at RRCC and the time management class that I am taking this semester.  Being an electrician has been a very enjoyable career choice so far, and I look forward to all of the opportunities I have in the future.

Inductive proximity sensor from Automation Direct.

At my current job site, we received a very simple job to do:  install a simple circuit which would activate strobes upon opening a pedestrian gate for a walkway which crosses an area with forklift traffic.  The engineering company gave us a box of parts:  A multi-function timer with on-delay, off-delay, and recycle modes with one normally open contact; inductive proximity sensors with one normally open contact; a fuse holder; and, strobe lights.  Everything was 120V, so there was no transformer.

In short, the proximity sensor would sense when the gate was opened, and energize the timer which would in turn immediately energize the strobes.  When the gate was closed, the timer would begin timing (off-delay) and when it timed-out, the strobes would de-energize. We had not yet received the drawings, but the circuit was very simple, so I drew-out what it would most likely be with the parts we were given:

Original circuit, shown with gate open.

There was a very obvious problem with this circuit.  Since the proximity sensor had the gate in its sensing field when the gate was closed, the strobe would always be on unless someone held the gate open for more than the set time on the timer.  Upon sharing my findings with the engineering firm, they produced the drawings which showed the same error.  I came-up with three solutions, two of which were the correct thing to do, and one which isn’t the best, but allows it to work in normal situations.

Solution 1:  Purchase proximity sensors with a normally closed contact.  When the gate is closed, the proximity sensor will change the state of the contact to normally open. When the gate opens, the proximity sensor will revert to it’s normally closed state, and the timer will activate and thus the strobe.  When the gate shuts, the timer will start and the strobe will turn-off when the timer times-out:

Normally closed proximity sensor, shown with gate open.

Solution 2:  Purchase a relay with a normally closed contact that we can interpose between the proximity sensor and the timer which behaves the same as if we had a proximity sensor with a normally closed contact:

Relay, shown with gate open.

Solution 3:  Move the sensor away from the gate’s closed position, but within the path of the gate’s swing so as to sense the gate as it is opened and closed.  This would use the original circuit and no additional parts would be purchased.  The downside is that if the gate is held open, the timer will time-out and the strobe will not be on.  Possible scenarios include people propping-open the gate while moving something heavy, or a longer line of people moving through the area, with one person holding open the gate.  As long as the gate is under normal use, meaning a person or a few persons are moving through the gate and allowing it to shut, it will work just fine.

As of now, solution 3 was chosen by the engineering firm.

Update:  It turns out that there is enough leakage current going across the proximity sensor to keep the timer constantly energized so that it never turns off.  The timer also appears to not allow enough current to flow across the proximity sensor to allow it to change states.  Therefore, we are going with solution 2 by adding a relay, which means I can move the proximity sensor back to where it is constantly sensing the closed gate.  A much better solution overall and it produces the outcome that the customer desires.

Teco SG2 v3 PLR

Two weeks after our latest family addition was born, my wife began to reach a level of tiredness that can only be obtained after two weeks of nursing constantly with little bits of sleep here and there.  While feeding our child at night, my wife was having a difficult time being able to time 15 minutes with the clock.  I searched for commercial products which were simple timers that could be preset with large buttons and obvious indicators as to the timer’s state.  I came-up empty, so I made my own.

The Players:

• Teco SG2 12HR-12D v3 PLR (programmable logic relay) and its DC power supply
• Automation Direct illuminated combination start / stop station

What I needed was simple:  a timer that was preset to 15 minutes, capable of being paused, easy to reset, and which had an indicator that clearly showed the state of the timer.  The easiest way I could think of accomplishing this was to use my trusty Teco SG2 PLR and a combination start / stop station with a built-in indicator.

Starting with the wiring, I connected the start and stop switches as inputs to the Teco, and connected the indicator to the first output.  I drew-up a quick design, listing the major states of the timer, how they would be enabled, and how they would be indicated.

Quick Design Overview:

• Timer not enabled, no indicator, activated by the red button if timing or paused (reset)
  

  Start / Stop Station

• Timer timing, steady indicator, activated by the green button if paused or not enabled
• Timer paused, slowly blinking indicator, activated by the green button once timing has commenced
• Timer done, fast blinking indicator, activated when the internal timer is done (16 minutes = 15 mins. feeding + 1 min. for “setup”)

The following shows the actual ladder logic program I used for this timer.  It is quite simple, using the two switch inputs (I01 & I02) and one indicator light output (Q01) on the start / stop combo, which comprises all of the external inputs and outputs.  M01 is an internal timing status flip-flop relay which allows me to use the green button switch for both start and pause.  T01 is the main retentive timer, set to 16 minutes (960 seconds).  T02 and T03 are the timers used for slow and fast blinking, respectively.  G01 is a compare operation, which on the Teco SG2 is an output (it is often an input on PLC’s), so it required its own line on the ladder diagram.  It is used to ensure that the timer (T01) is timing before the blinking pause output will be enabled.

You will see that G01 has a V after the numbers in the block off to the side of the coil.  The compare function on the Teco SG2 is primarily for comparing analog voltages, but it can be used to compare any two numbers.  In this case, it is comparing the accumulated time in T01 against “0″ to ensure that the timer is some number greater than 0 and has therefore begun timing.  This way if the timer has not started timing, the indicator light will not be blinking.

Click to Enlarge.

The indicator light also makes a great night light.

Here is a zip file containing the ladder logic diagram: Feeding Timer.  You can download the SG2 programming software, load the ladder logic program, and start the emulator to see how it works.  You can change it and play with it all you like.

From Red Rocks Community College, I completed my degree-seeking education which I began in the summer 2008 semester.  I now hold two AAS degrees: Construction Electrician and Maintenance Electrician, with honors.  I also earned the Advanced Instrumentation and Controls Technician certificate as I completed all of the controls classes that were available in the electrical program.

From IEC, I completed the apprenticeship training program which I began in the Fall of 2009.  I was recognized as the top student for my class.  I won the regional wire-off competition, earning the title Apprentice of the Year for the rocky mountain region.

Of course, my education will never be complete.  There is so much to learn and experience and I love to learn.  There are a number of classes I would like to take, and I plan on taking one to two every semester, beginning with time management.

I have 600 hours remaining until I can test for my journeyman’s license and it can’t get here soon enough.  That said, the closer and closer I get to having my license, the more and more I realize that I know less and less about being an electrician.  There are so many facets to the trade that it will take years to master, which I think is great – I love a good challenge.  I look forward to all of the learning and experiences I will have in the future in such a fun-filled vocation.

A huge thank you to all of the companies who donated prizes to the wire-off participants.  Here is a list of my loot:

• Paid day-off from Encore Electric which allowed me to compete without using vacation time
• $500 Home Depot gift card, donated by The Home Depot
• 2 x $100 Home Depot gift cards, donated by Carlton Electric
• Ideal 61-773 Clamp Meter bundled with a NC Voltage Tester, donated by Ideal Industries
• Ideal 36-314 six-piece TKO Electrician’s Hole Saw Kit, donated by Ideal Industries
• Carhartt Jacket, donated by Stewart & Stevenson
• Klein 18″ canvas tool bag, donated by Klein Tools
• Klein Insulated 3/16″ Screw Driver, donated by Klein Tools (Now I can do hotwork!  Just kidding Jack.)
• Klein NC Voltage Tester, donated by Klein Tools
• Milwaukee Tools-branded portable poker table, donated by CED
• A t-shirt featuring Scotch-brand electrical tape
• Three embroidered baseball caps from Stewart & Stevenson, Bosch, and Graybar

For the Top Student award, I was given a Klein 14-piece tool set and a pay raise from Encore Electric.  Thank you again to everyone who made the competition possible.

2011 Convention Schedule
National Apprentice of the Year Competition

Once everything was numbered and all the parts were inventoried (about a 30 minute process), I began to mount the cabinet and boxes.  That took me two hours.  I can’t believe it took that long, but with 3 pieces of conduit (two short four points and one rolling offset), the cabinet, the disconnect, and the two little boxes, with me attempting to make them perfectly level and at the desired mounting dimensions, the time just flew.

Once that was complete, I had 3 hours left and went to work wiring.  I knew it would take me about 3 hours, so I was O.K.  When 5:15pm rolled around with 45 minutes remaining, I was almost done with all the hot wiring and had only the door indicators, the neutrals and my wire organization to do (sticky backs and cable ties).  I ran all of door wires, then the neutrals and had a whopping 15 minutes remaining.  I slapped-on the sticky backs as best I could, cable-tied them, and cleaned it up considerably.  I had a whopping 5 minutes to spare, which was plenty of time to clean-up.

By this point, two or three other people had finished their project and had them tested.  I knew that they worked because they were not given the additional ten minutes to find and correct any problems, so I knew mine had to work right the first time, or I was out of the competition.  Normally when I do a control circuit, I check a few things here and there, but I had no time to do that.  Thankfully I had spent the time at the beginning assigning contact numbers to all of the contacts and the coils as well, so that the wiring was pretty fool-proof.  I was fairly confident, but not as confident as I would have liked to have been.

The testing judge came over and powered-up the system.  The red light came on, phew.  Then he had me start it, and I watched the run indicator, timers and then the horn, starter, and contactor work and alternate like they should.  Only one thing left to test.  I switched the system to reverse and jogged it successfully, with the proper light illuminating.  Everything worked correctly the first time.

The inspectors visited after that.  Everything was mounted properly at the designated heights and spacing and was bonded properly.  There was an issue with how the disconnect was wired, but I did it to how I was told when I asked as there was no direction in the instructions if it was a system disconnect or not.  I was told not to worry about it as it appeared to be a common problem.

This year’s regional wire-off champion will be announced on June 4th at IEC’s graduation.  Just 23 days to wait…

My muscles are finally starting to relax (and starting to hurt from being tensed for six hours) and the mental intensity I felt is now gone and I can finally just chill.  I really don’t ever want to do that again, unless it is at the national competition in October =).

We were told that we would be called next Monday to notify us if we were one of the ten who made the local finals.  Monday sure is a long ways away.

All of the fourth-year students who attended the competition last night had the option of not coming into school today, but I went anyway, and I am glad I did.  One of the judges saw me in class.  He had completed his review of all of the control circuit ladder diagrams, and he told me congratulations that I made it into the wire-off finals! He also let me know that mine was the only one that successfully worked to meet the criteria of the word problem.

I am now on to the local finals on May 12th.  There are ten of us and only one goes on to the national competition.  I plan to be that person. I will be wiring control circuits as much as I can between now and then, in the midst of my project management class final and term project.

Teco SG2 v3 PLR

On my current project, my company was required to install pole lights for a temporary employee parking lot to be used during the construction of a new building. The service from the utility for the pole lights would not be installed until after the parking lot began to be used, so a rental generator was ordered as an interim power solution.  In order to run the pole lights at night, a time clock was needed.  Expecting a standard time clock, I was surprised when the generator rental representative presented the Teco SG2 PLR.

The Players:

• Multiquip DCA70USI WhisperWatt Ultra-silent Generator (it is amazingly quiet) with a set of terminals for the autostart feature
• Teco SG2 12HR-12D v3 PLR (programmable logic relay)
• Pole lights in a parking lot

Thankfully I was familiar with the Teco SG2.  I had experienced it as a side-project at IEC’s school, as well as in one of its alter-ego forms, the Allen-Bradley Pico, at Red Rocks Community College.  The generator is equipped with a 2-wire terminal block for its autostart feature, requiring a dry set of a contacts from a relay controlling the condition of the autostart.  One of the output contacts (Q1 in the picture) on the Teco SG2 PLR would suffice.

Simple wiring diagram. Click to enlarge.

Only a few steps needed to be done to configure the SG2 to start the generator.  The first step was the physical wiring.  The SG2 required 12V DC power, so I connected the negative power input of the SG2 to the generator chassis and took the positive power input from the hot side of the autostart terminal block.  I then connected a second wire from the hot side of the autostart block to the common of the Q1 relay output on the PLR.  The normally open (NO) side of the Q1 relay was wired to the other side of the autostart terminal block allowing the Q1 output relay to control the autostart on the generator.

The next step was to program the SG2.  Although I had never programmed it from its front panel (I had always used a computer as an interface), the procedure proved to be quite intuitive.  The keys are self-explanatory, and the menu system is straight forward.  I checked the system time on the internal clock and set it to the current time. Then I went into the ladder program and went to work.  There was an existing program which I erased.  I added a real time clock (RTC) on line 1 to regulate the start and stop times of the generator so as to control when the pole lights in the parking lot were on or off.  The RTC comes with several modes.  I chose mode 1 (daily timing), entered Sun-Sun (Sunday through Sunday), and set the on and off times (7pm to 7am).

Simple RTC. Click to enlarge.

On line 2, I added a NO contact tied to the RTC’s internal coil, and on the same line as the NO contact, the Q1 relay output coil.  So, when the RTC activated, its NO contact closed and activated the Q1 output relay, thus starting the generator.  We put a couple of test times in the RTC for testing and it all worked as it should.  All was well until…

One of our foreman stopped-by later that night to make sure that the lights were on.  They were not on.  Upon inspection of the generator, it was in a fault condition.  He switched the generator to manual and went home.

The next day, we did some tests and found that the timer was working properly.  The generator had an internal fault that manifested itself one other time when we switched it to manual which showed us that we could not rely on the autostart feature.  Since we were using the generator for only a couple of weeks, the easiest path was to change the start time to 10 minutes before we left at the end of the work day so that we knew the generator had started.

That said, I decided to write a program that would handle this fault and be more fault-tolerant in general, just for fun.  I incorporated a way to handle any glow-plug preheating and any condition where the generator did not start in 10 seconds, such as the internal fault we are facing.  Below are images of both LogixPro (a good program for quick program prototypes) and Teco SG2 ladder logic programs.  I did not find a way to access the enabled bit for the timers in the SG2 (though I did not look very hard, nor did I look at the timer files), so I just used their done bits, which changed the way I implemented the logic in the SG2 version from the LogixPro version.  I also added a message to the screen of the SG2 to show when it went into a fault condition.

The SG2 program basically does the following things:

• Controls the generator autostart and run with a real time clock (RTC)
• Attempts to start the generator for 10 seconds
• If the generator does not start in 10 seconds, it rests for 50 seconds and tries to start again
• The start procedure is attempted 5 times.  If it does not start on the 5th attempt, the SG2 displays a fault message.
• If the preheat indicator light activates on the generator, the 10 second start timer is stopped so that the generator can preheat for as long as it needs without affecting the 10 second start window.  I02 would be connected to a NO set of contacts on the same relay that turns-on the preheat indicator light on the generator.
• A voltage monitor (could be a phase monitor or as simple as a 277v relay) connected to I01 monitors the status of the generator to indicate if it is running or not.
• The fault counter is reset either by pressing the up arrow on the SG2 interface or when there is a successful start of the generator.

LogixPro. Click to enlarge.

SG2. Click to enlarge.

Here is a zip file containing both ladder logic programs: Generator Auto Start Timer.  You can download the SG2 programming software, load the ladder logic program, and start the emulator to see how it works.  You can interact with it by activating the I01 and I02 inputs (preheat and voltage monitor).  You can change it and play with it all you like.