Career Path > Training, Tests & Education
I&C Exams/Certifications
RDTroja:
--- Quote from: UncaBuffalo on Aug 22, 2008, 02:04 ---
Envelope please....
....and the winner is....
ME! :)
Yep, I get to be an I&C tech! Thanks for all the help from everyone who replied here or via PM!
--- End quote ---
Congratulations. Now you can start bugging the RP techs about having to wear gloves to do sensitive work in containment. ;)
Seriously, congrats and good luck!
IRLFAN:
--- Quote from: Broadzilla on Aug 01, 2008, 09:11 ---
When I was with DTE I don't recall we ever hired anyone off the street into I+C. Usually if they needed someone an Ex ET from Ops would get the job.
Mike
--- End quote ---
Not lately Mike. The last several times we hired techs, none have come from ops. Why? Simple, DTE refuses to hire any Navy RO's for ops because they know that they will bid out to maintenance.
John
UncaBuffalo:
--- Quote from: RDTroja on Aug 22, 2008, 02:27 ---Congratulations. Now you can start bugging the RP techs about having to wear gloves to do sensitive work in containment. ;)
Seriously, congrats and good luck!
--- End quote ---
Actually, I was wondering...
...I know the RWP says double-everything...but would it be okay if I took my outer gloves off for just a second for this one adjustment...
...and how about if I just use onion skins for my inner gloves?
...and could I take one of them off for this super-fine screw? I've got cotton-liners on?
Oops! Now where did all that water come from!?!? ;)
Hey! Since I'm probably crapped up anyway, how about we finish this job in modesties? Sure would be cooler! :)
UncaBuffalo:
--- Quote from: proud dad on Aug 03, 2008, 01:13 ---My work is way down the line from you guys and most of what is written here is beond me,but still fun to read and learn.I must ask,what is a DC transformer?
--- End quote ---
http://www.butlerwinding.com/elelectronic-transformer/pulse_transformer/
Pulse Transformers
The magnetic flux in a typical A.C. transformer core alternates between positive and negative values. The magnetic flux in the typical pulse transformer does not. The typical pulse transformer operates in an “unipolar” mode ( flux density may meet but does not cross zero ).
A fixed D.C. current could be used to create a biasing D.C. magnetic field in the transformer core, thereby forcing the field to cross over the zero line. Pulse transformers usually (not always) operate at high frequency necessitating use of low loss cores (usually ferrites). Figure 1A shows the electrical schematic for a pulse transformer. Figure 1B shows an equivalent high frequency circuit representation for a transformer which is applicable to pulse transformers. The circuit treats parasitic elements, leakage inductances and winding capacitance, as lumped circuit elements, but they are actually distributed elements. Pulse transformers can be divided into two major types, power and signal.
An example of a power pulse transformer application would be precise control of a heating element from a fixed D.C. voltage source. The voltage may be stepped up or down as needed by the pulse transformer’s turns ratio. The power to the pulse transformer is turned on and off using a switch (or switching device) at an operating frequency and a pulse duration that delivers the required amount of power. Consequently, the temperature is also controlled. The transformer provides electrical isolation between the input and output. The transformers used in forward converter power supplies are essentially power type pulse transformers. There exists high-power pulse transformer designs that have exceeded 500 kilowatts of power capacity.
The design of “signal” type of pulse transformer focuses on the delivery of a signal at the output. The transformer delivers a “pulse-like” signal or a series of pulses. The turns ratio of the pulse transformer can be used to adjust signal amplitude and provide impedance matching between the source and load. Pulse transformers are often used in the transmittal of digital data and in the gate drive circuitry of transistors, F.E.T.s, S.C.R.s, and etc. In the latter application, the pulse transformers may be referred to as “gate transformers” or “gate drive transformers”. Signal type of pulse transformers handle relatively low levels of power. For digital data transmission, transformers are designed to minimized signal distortion. The transformers might be operated with a D.C. bias current. Many signal type pulse transformers are also categorized as wideband transformers. Signal type pulse transformers are frequently used in communication systems and digital networks.
Pulse transformer designs vary widely in terms of power rating, inductance, voltage level (low to high), operating frequency, size, impedance, bandwidth (frequency response), packaging, winding capacitance, and other parameters. Designers try to minimize parasitic elements such as leakage inductance and winding capacitance by using winding configurations which optimize the coupling between the windings.
Butler Winding can make (and has made) pulse transformers in a wide variety of shapes and sizes. This includes; various standard types of “core with bobbin” structures ( E, EP, EFD, PQ, POT, U and others ), toroids, and some custom designs. Our upper limits are 40 pounds of weight and 2 kilowatts of power. We have experience with foil windings, litz wire windings, and perfect layering. For toroids, we can ( and have done ) sector winding, progressive winding, bank winding, and progressive bank winding.
UncaBuffalo:
--- Quote from: Creeker on Aug 02, 2008, 07:40 ---When I hired into my present utility, we had an I&C test which contained the following:
1. Basic Electronics -- Resistor color codes, ohms law, KVLs, KCLs, capacitance, inductance...
2. Power triangle type problems
3. LOTs of detector problems... LVDT, dry reference leg vented to atmosphere, atmospheric pressure changes, what happens to displayed pressure.. That sort of thing, for every different type of detector configuration you could imagine.
4. Not much at all on PLCs
5. No hard core stuff... encoder wheels, etc, but there was a couple transducer problems, RTD and thermocouples...
6. No AOV stuff that I can remember, but maybe a question or 2 on reference leg's being cracked open on a 5 valve manifold.
That's about all I can remember!
Bill
--- End quote ---
Okay, here was my (successful) study routine:
1. Looked thru all of my old notes and texts...sometimes seeing info in my own handwriting, or a text I was familiar with, would open a floodgate of memory...and sometimes it was like reading Greek (esp. my own notes!)
2. Checked out every book that was even remotely related at the two local libraries. Since we have a pretty good tech college right here, that amounted to about 50 books that I gave at least 10 minutes to...and 15 that I read parts of in-depth. I think it really helped to review a lot of different texts, because I became familiar with multiple ways of looking at & wording the same concept. This can be very handy when you are taking a test from an unfamiliar source.
3. Crammed hard for the last 2 or 3 days from the texts I found most useful. These (in addition to my notes from college) were:
Electronics Math, R. Jesse Phagan
Electronic Devices, Thomas L. Floyd
Applied Electricity & Electronics for Technology, Rodney B. Faber
I also spent some time with the CET Study Guide...a lot of it is NOT applicable to I&C work, but I find it helps to take practice tests to get myself in 'test-mode'. The CET tests were the only ones I could find that were even in the ballpark.
Review the post from "Creeker"...he was right on!
Also, study some things that you might not consider to be electronics or I&C...fuses, relays, circuit breakers, etc...
Hope this helps someone in a similar situation! :)
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