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Lack of relay engineers

Lack of relay engineers

Lack of relay engineers

(OP)
One friend of mine on day told me... "do you know why I am replacing all my electromechanical and static relays with the numerical ones?" I answered: "the old ones are broken and you don't get the spare parts, maybe?"
He said "no, no, the old relays are working perfectly. That's not the problem".
"So whay then?", I asked...
"I loose the young engineers if I ask them to take care of plants with old technology. After some months they say 'thank you very much, I go somewhere else, where I can use what I studied for..':"

Ok, I have "painted" it a little bit, but this was the main meaning of the discussion anyway. What is your opinion on that?

RE: Lack of relay engineers

I would say that the principles are the same.  I guess maybe he is hiring the wrong people.  Usually once relays are set, unless there is changes in the plant there is not alot of interfacing with the relays.  Testing will be basically the same except that with the newer relays there are more functions in the one relay.  So, a relay test engineer should not be concerned whether it is a digital relay or an EM one.  He should be looking at the response of the relay to a given input.
The analysis behind setting the relays is the same.  So if he is talking about a Relay setting engineer (protection engineer) the math and analysis will be the same.  It maybe more fun or easier to set the relay up thru a laptop but it is still setting a relay.

RE: Lack of relay engineers

Well, there is not just setting the relay... there is troubleshooting when the relay trips.  A lot more info to analyse if you have digital relays and digital fault recorders.... more interesting than just looking at a few flags.

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

RE: Lack of relay engineers

True, depends on how complex the system is.  Maybe that's the real issue, not a very complex system so no real need for DFR's and waveform analysis, modeling the sequence of events, etc.

RE: Lack of relay engineers

The old relays are a great place to learn skills needed by a protection engineer. The new ones do so much of the work for you that the understanding required is lower in many areas. I'm not saying a setting a digital relay is necessarily easy - far from it - but someone who is familiar with the electro-mechanical type will be up to speed on a digital relay faster than someone who is familiar with a digital relay will be on an electro-mechanical type.

Expanding on what ePete said, interpreting a fault from the operation of mechanical relays takes more judgement and arguably better understanding of the system than with a modern relay. OTOH a digital relay records and presents so much more information that on a complex fault it may provide the only means of identifying the origin of the fault, and any time saved on diagnosing simpler faults has a direct benefit to the bottom line.

Given the choice I would work with a digital relay any day because it makes my life easier (except when they go wrong, or won't talk to my laptop!) but understanding the older technology is invaluable.
 

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  Sometimes I only open my mouth to swap feet...

RE: Lack of relay engineers

While most new digital relays provide some wonderful info, they also provide something not so good.
Data diarrhea.  Lately, I've seen more than one engineer get tied up in all of the information and lose sight of what was really going on.  
Basically, EM relays have provided very good service for many years and while some companies are shedding them in favor of the new stuff, we are likely to have EM for many, many years to come. Getting rid of existing EM relays that do most protection jobs just fine(and have been paid for 25+ years) isn't high up on the prioriy list for everybody. Sitting with gaze affixed at the screen of a laptop like it is a crystal ball holding all the answers may be the trend nowadays, but working with EM systems and learning from that seems to me invaluable.
I know it sounds cliche, but how the hell can you know where you are going if you don't know where you've been?
You asked for opinions....

RE: Lack of relay engineers

Hiya-

Well, I guess you can't "fault" (o.k. bad pun) the youngsters by wanting to do the "state of the art".  They are still in a learning curve, but more importantly, they are building their resume.

Might I suggest that you do "replacement" upgrages with digital relays?  This way, the younger ones get the benifit of BOTH technologies? Wait for the old statics to die and replace with new technology?

New designs do digital.  I know it's kinda "funny" having  to use more than what is needed just to keep your staff happy, but sometimes engineering is more than just dealing with the technology.

There is a very serious implication for a new engineer to have the "latest and greatest" "tools de-jur" (hot tools).  Most Human Resource types are ignorant and only look at resumes that have specific buzz words.  Not the right buzz words, the resume gets tossed before the hiring engineer or manager even looks at it.  In fact, I wouldn't be surprised if the resumes are just scanned by computer looking for the right "buzz words" and a "ranking" applied to them.  Not the right number of buzz words, then your resume gets tossed.

Besides, if they didn't want to "play" with the new stuff, they wouldn't be engineers in the first place!

In my segment it is especially volitle.  Little terms like "Python", "AJAX", and "Ruby on Rails" are very important buzz words.

  Cheers,

    Rich S.

RE: Lack of relay engineers

Hi RichS,

Protection is a conservative (small 'c') business and relay engineers are usually a pretty conservative bunch when it comes to embracing new technology. There are old fashioned relays in service which are fully operational and which were installed when my grandfather was my age. They still work perfectly well and pass their tests each time. I wonder whether even the best of the modern relays will ever be able to make such a claim? In spite of my bias toward the digital relays for complex schemes I am still a big supporter of the E-M relays in the right application. Simple = good in a device which may have sit for 50 years and only operate in anger once.
 

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  Sometimes I only open my mouth to swap feet...

RE: Lack of relay engineers

Hi.
It's big problem today.
My team work in 3 areas: sales, design and commissionig of protection system and connection to SCADA.
For sales is good use words "state of the art", event list, synchronizathion by GPS,TCP/IP communication, IEC61850, computer test, etc.
Connection to SCADA also "intresting": protocols, hot stand bay, RAID5.
Today each tender documents include 80-90% requrements for type of computer, laptops, printers, network switch, etc.
Maybe 10%, protection requrements.
60% of time my team work with laptops: install new HMI, check communication( USB to COM convertors), backup's.
But we forgot, digital relay is only part of electrical system (important, but is part), many options is only "nice to have". 95% of faults are wrong design of CT,VT wiring and size, DC supply, control circuits, trip curcits. Wafeform not help im these cases. Wrong setting calculation ( I like setting as 1456.7A, for CT 200/5). And young's put this setting and check with computer test system set-points ( 5A secondary setting it's work with 4.99A or 5.01A), but forgot about polyrity , volt drop and megger test of CT wiring. check of wiring from point to point is not for young's, is not "intresting".For example, before several month we check some cubicle with transformer diff protection: we started from current wiring and see cable from CT (30m) with 2.5mm^2 and into cubicle wiring 1mm^2, I asked design team, why, answers what is a problem , it's only 5A.
Sorry, young's, I'm also young, but I start with EM relay.
My pinion: digital relay option, connection to SCADA are only help to us. Each protection engineer must start from EM relay scheme, test wiring and test relay with simple Sverker650.

RE: Lack of relay engineers

Hiya ScottyUK-

No arguements on the effectiveness on older equipment.  The technology aside, it would be great if the OP will give the younger engineers experience in both technologies.  The experience on the resume allows the engineer moving on more choices at a different job.  That's all.

  Cheers,

   Rich S.

RE: Lack of relay engineers

I think it is a case where familiarity of the entire operation may lead to satisfaction where as just looking at isolated relays could seem a bit dull.  

I've had a great time lately, troubleshooting circuits protected by old relays (and saturated CT's !!) but it has taken me 20 years to appreciate what is really going on (and I'm probably still guessing more than 50% of the time).

RE: Lack of relay engineers

(OP)
I have of ocurse my opinion, but I'll tell you later.
Young engineers where are you?
You are used to use Forums, so , please, jump in and comment..... if you are still in the field.. smile

RE: Lack of relay engineers

I have to agree with Scotty UK that the EM relays are a very good platform for learning the fundamentals of protection.  Workiing with multifunction relays provides a less effective learning experience in my mind for two reasons: 1. Much of the time is spent leanring the interface between the computer and the relay (different for every dang one of 'em!); 2. The multifunction relays have a simplified means of setting and testing some functions such that you never have to learn them in depth.

On a more important note, it seems a prejudice has come to light here.  In defense of relays everywhere, I have to stand up to ScottyUK's assertion that they operate in anger!  

Frankly ScottyUK, I never took you for an anti-relay-ite.

Cheers, JB

RE: Lack of relay engineers

JB,

I should probably have said 'operate in panic': imagine sitting at peace with the world for years and suddenly - bang! - there's 50kA on the loose! Ouch! tongue
 

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  Sometimes I only open my mouth to swap feet...

RE: Lack of relay engineers

(OP)
My opinion:

1) Good point that electromechanical relays help in understanding, but one relay engineers should have knowledge of power system analysis in faulted situations. The EM relay does not help on that.

2) Completely different approach in testing EM or numerical relays. If one EM relay (overcurrent for instance) should trip at 1A, and it trips at 1.2A, you change th epotentiometers of it till you get trip at 1A. This you never do with a numerical relay. People with EM relay knowledge in the background tend to do it,and it is wrong.

3) It is not nice to go to a substation with the screwdriver, mirror, lubricant etc, for one guy that has studied z transform at school, even if the relay works fine. You will loose that guy, if he is good.

4) Data diarrhea. Ok, too many information is NO information. Correct. But thanks to data diarrhea (nice wording.. smile  ) you can do a post fault analysis and correct your settings (for instance power swing speed, resistive reach for distance protectio). The new setting proposal is supported by this data diarrhea. Better than suppoorting it by nothing.

5) Testing a multifunction relay is equivalent to test a protection cubicle with EM relays. It is not the relay that is complicated, it is the fact that "the progress" has put the cubicle in a small box that we still call "relay". It was not easy to test a cubicle before, it is not easy to test an integrated device today. You need electrotechnical competence.

6) Numerical relays provide a power system modelling closer to the mathematical modelling we study at technical schools. To test it, you have to understand the mathematics of it (vector diagram rotation for transformer differential.. the interposing CTs are now INSIDE the device..). It is more interesting.

7) Learning the PC interface to the devices? It's absolutely NOT a problem for one guy who is used to connect the playstations together. The problem for him is when he has to use a DOS PC to manage the interface, old RS232 etc.

So, I fully agree with this friend of mine. He really opened my mind on that. I am just sorry it was NOT my idea..

RE: Lack of relay engineers

Hi 521AB.
Used digital relay or EM is not Q.
Of course digital, sorry not digital: numerical relay with PLC, metering option and other options. Today is terminals: like to T60, G60, REF54_, RET54_, F650 and, and, and....
I'm agree with each your word.
We will continue w/o end , what is better in digital relay.
I'm work only with digital relays 10 years and don't want back to EM relay or electronic relay.
But, I writed about learn of young engineer, about "intresting" and "not intresting".
My opinion, for good learn young's must start from EM logic.
Sorry for example, We not start from Boing 747 or Ferrari.
I'm work with protection relays 15 years and only start understand what is it protection. I see, not only I'm.
I'm like our job ( is not simple job) and I'm sure only expirence can help us ( of course vector diagram, disturbance recorder and station event list from digital relay help us also).
521AB, it is intresting, that we think same. Before several days, I told to customer abot digital relay HMI, it's like to DVD or TV HMI, what is a problem.
But please don't forget about:
Your DVD don't work correct,...O.K., your generator protection send unwanted trip to 250MVA generator ( my "good" expirence)it's problem.

RE: Lack of relay engineers

Dang Scotty - I do believe you are the philosopher among us. :)

RE: Lack of relay engineers

Well, I'm a young relay engineer so I can answer how I feel about things...

There is a lot for me to absorb in this industry.  My mentor is exposing me to lots of different types of relays.  Since my company has and will continue to have lots of electromagnetic relays in the field, I know that it is important for me to learn all I can about both.

I may have some preference to digital relays because I feel like I am learning some aspects of it very quickly.  For instance, I may not have the best grasp of what the settings should be, but I am already good at putting the settings into the relay, checking the logic, and making certain the settings in the relay do what my mentor thinks they do.  Some of the mistakes I've found I have to wonder if he put there on purpose for me to find, or if they were just the result of a hurried draft.

So with digital relays I feel there are more intermediate levels of knowledge... but with electromechanical it seems like you either know it or you don't.

I've only been a young protection engineer for a month, and my prior experience is just a master's degree in electrical engineering.  I'm excited about learning everything I can, because soon everyone else in my company is going to retire!

RE: Lack of relay engineers

Thought those who like the digital relays would enjoy these diagrams of how things used to be. Taken from 'The Protective Gear Handbook' published by Pitman and Metropolitan Vickers in 1953. Files are ~ 1MB each so broadband only.

http://img82.imageshack.us/img82/2143/skmbtc25201042715502oe7.jpg
http://img267.imageshack.us/img267/5464/skmbtc25201042715510wu2.jpg

 

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  Sometimes I only open my mouth to swap feet...

RE: Lack of relay engineers

I am stuck somewhere in the middle - not too young, not too old.  From my perspective, I believe having an understanding of the EM relays provides a solid basis for understanding the system.  You cannot agrue the physics of an EM relay.  I have too often seen someone think they have a thorough understanding of the system because they can set a digital relay, only to find out that their understanding is not quite so good.

Also, at 3 AM when the line or generator trips many old school engineers or techs can have the problem identified with EM relays and event recorder data before a young engineer can connect to the relay and download the data.

As in the old Karate Kid movie, wax on/wax off may have seemed boring and unrelated to karate but in the end it all made sense.  The same goes for EM relays and power systems.

RE: Lack of relay engineers

Nice discussion, sorry that I missed it. Last days I was on site testing of (numerical of course!) generator protection. All functions in one not very big box. Including vector diagrams via Web interface. Everything was well until the moment when after energizing we read Idiff=0.08In and Irestr=0.19In. surprise Many additional measurements were done, vector diagrams were analized and finally we enter the cell under the Gen to find that starpoint CT's were wrongly identified and we have cyclic phase transposition in secondary circuits! (Please don't blame me - I am only relay protection subcontractor for this project!!!). Morale: Good secondary circuits technician is invaluable in commissioning works. Numerical technology is something nice (although for me is a bit boring to read 500+ pages Manual of O/C protection), but as slavagar mentioned, most of problems are usually related to wiring or other simple thinks.

521AB described specific of numerical technology very well (as usual in his posts!) as a protection panel in one box. This is very close to my favorite joke with computer guys that for me the laptop is just a HiTech screwdriver, because   using it I connect various functions like in the past we connected various relays to complete the protection scheme. You should see the face of our SysAdmin  purpleface !

Regards,
LZ5PL, 24 years 1 day as commissioning engineer and control & protection designer.
www.triel.bg

------------------------
It may be like this in theory and practice, but in real life it is completely different.
The favourite sentence of my army sergeant

RE: Lack of relay engineers

ScottyUK,

Thanks for the drawings.  They look very similiar to full size dwgs I have here of systems still in use.  I have also referred to a 1923 edition of the Electrical Engineer's Handbook that came with my office for info on some devices still in use.

RE: Lack of relay engineers

ScottyUK, thank you for nice schematics! Two years ago I had to connect two new feeders into similar BB protection installed by Chinese 30+ years ago on 110 kV s/s in Albania. It was really an exciting job :) !

I like to collect old schematics, especially of tube radios, but also from my professional field.

------------------------
It may be like this in theory and practice, but in real life it is completely different.
The favourite sentence of my army sergeant

RE: Lack of relay engineers

I want to commment on this as well - as a fairly new young engineer. I started my career designing and testing micro-processor relays for a relay manufacturer. I now work in the consulting industry with a senior protection engineer.

Anyone who bored by the EMs should reconsider. If you look at how our predacestors did things and the cool ideas that they had - one will only be amazed. The new relays only immulate the old EMs.

I have been exposed to both and I love them both for theier features and 'lack of features.' Just think, no one can hack into a EM and tell it to trip remotely (in todays world a definite possiblility with new relays).

I only hope to gain the knowledge of the older protection engineers before they are all gone - they have kept indutry and the utilities going for years! Thank you all!!

RE: Lack of relay engineers

(OP)
Eleceng01 and all of you.
It is not true that numerical relays "emulate" EM relays. They did it before, but not now, propably because of generation change. We have designers that are thinking in z transform directly -read samples- instead of thinking in s transform (read linear differential equations, or sometimes just phasors) and converting their s-results in z results.

The task of the protection relay is to trip when there is a fault in the protected area, and not to trip if there is a fault, but not in the protected area. Of course it is also not to trip if there is no fault, but this is easy and obvious.
So, the relay must perform a sort of "pattern recognition", and has a very little time available to do that. Knowledge of power systems in faulted situations is today just the minimum background to design a relay,

Today the digital relay lives in the digital world, and not in one "digitalized analog world". Everything is open to the progress.

RE: Lack of relay engineers

521AB and all,

I guess I should have chosen my wording more correctly - 521AB is right. I was just trying to point out that understanding the old EMs will help in thinking about the new relays.

RE: Lack of relay engineers

(OP)
Eleceng01,
don't worry how you choose your wording...
This is a very interesting discussion and I think that we will flat it down if we think too much about our wordings. I din't want to say that I was right or that you are wrong, even if I said it ( smile ).
You are very valuable in this forum, as you are a "young protection engineer", and I think we all need persons like you. Not only we "old" engineers, but also the society.

I am completely in agreement with you when you say that understanding EM relays helps. Definitely it helps, but today there is almost no connection between one busbar differential relay with diodes, auxiliary circuits, coils, transistors etc and one fully numerical busbur relay.
The principle: "water in must be equal to water out", is the only thing they have in common (so far they still have the trip contact, but later this will also vanish and will be replaced by a GOOSE message).

Anyway: welcome!

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