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Relay & Control Panel Cost Reductions Project
16

Relay & Control Panel Cost Reductions Project

Relay & Control Panel Cost Reductions Project

(OP)
Are there any other utility engineers responsible for finding ways to lower substation costs for 2003.  I have been authorized/ordered to throw out our 100+ years of relay panel standards and start over with a clean sheet of paper on a new design for our relay, SCADA, and control panels to be built in the future.  Not wanting to reinvent the wheel, I thought I would begin with switching from our custom everything to more off the shelf components.  Has anyone blazed this trail already and if so, what are some of the problems to look out for?  Our substations are used to serve both areas of large cities to rural farmlands in Texas using votages ranging from 12kV to 345kV. I have been authorized to utilitize microprocessor based relaying for both transmission and distribution class subs, versus the old Electro-mechanical relays.  We have used one of the more common microprocessor brand relays for distribution class subs for the past eight years.  Management wants even more savings. So starting in January my standards are gone and an empty white paper will be staring me in the face.  All ideas are welcome, extremes included.  I will even have a budget for prototyping and testing in a lab so "reliability" will be maintained.  What are the most economical panel designs?  We currently use 19" rack mount for distribution class relaying and custom punch steel for transmission class relaying.  Is there anything else more economical?  We are looked at having turnkey systems manufactured by switchgear manufactures to getting ride of our steel fixtures the breakers are previously installed with to pole mounted reclosures with a control box on the opposite side with all the relays.

RE: Relay & Control Panel Cost Reductions Project

Suggestion: The newer type of integrated relaying can be accommodated differently than the electromechanical relays. It will consume less space even if redundancies of highly integrated protective relays are considered.

RE: Relay & Control Panel Cost Reductions Project


To some degree, reduction in capital-equipment costs need to be offset by appropriate (re)training costs.
  

RE: Relay & Control Panel Cost Reductions Project

2
jlgordon,
the company I work for also used to make their own relays components. Now we make practically nothing, we buy everything. My company also used to test in the laboratory everything we used in the substations. Now we test everything at site during commissioning. I won't discuss relay manufacturers, other companions have done that.

I can state that you may find issues with maintenance. For example we used to have a unique company number for each secondary relay asset. Now we use the product manufacturer's number.

You may find issues with your relay data base, about how to store the new relay settings. Do you store every single configurable point, or only the ones you use in the new relay? Or do you just store the relay settings as a file attachment to your electronic relay settings data base?

ReTraining may be found to be a big issue also.

Benefits: when a transitory fleeting fault occurs, you have some hope of capturing the event and post fault analysing it!!! You get a fault locator that can help you find the location of a fault along a transmission line of sufficient accuracy to be beneficial to your linesmen.

SCADA relay interfacing. You can use DNP3.0 or ethernet type connections to your relays. Ethernet means you can access your relays easily through your computer back in the office, but then there are firewall issues. Talk with your IT people, but be sure they don't take over your substation LAN work!
You could use DNP3.0 for now until the ethernet protocols are more robust.

There are my brief thoughts, hope they help!

cheers

RE: Relay & Control Panel Cost Reductions Project

I have found the ABB Ref543 relay to be excellent. It has hundreds of protection functions as well as metering etc.

Well worth having a look at.

Best of luck in you Herculean task!

RE: Relay & Control Panel Cost Reductions Project

I totally recommend you to check SIEMENS 7SJ63 relays. They have many protection functions and they also have logic functions in order to make switchgear interlockins. It is also possible to control circuit breakers, earthing switches etc. Everything is in one relay.

RE: Relay & Control Panel Cost Reductions Project

My advice would be to check the Alstom MICOM products. They offer digital protection functions as well as serial communications options (Courier, DNP, IEC etc.) They are also relatively CHEAP - the ABB REF543 relay mentioned above is an all singing, all dancing product but maybe 10x the price of a basic MICOM relay, if all you require are basic protection and SCADA type functions.

RE: Relay & Control Panel Cost Reductions Project

(OP)
Thanks for all the input so far.  Yes, we agree with all your suggestions.  We have been evaluating different relay mnf's. product lines for a while and are planing on bringing in some of the ones mentioned above.  Additionally; we want to go the next step and look at the whole cost; both initial and long term.  For example, we want to look at how the relays are physically put into service.  Are there less expensive methods of physically mounting/packaging/putting relays into service without increasing service interruptions and maintenance costs?  We have always had everything custom made to our perceived stringent needs, ignoring the rest of the world and their practices,  (ie: we use the green wire for trip circuits versus the ground circuit.)  We use special termination points for all cable wire tie points that allow easy circuit interruption.  Can we switch to more common items that are more "off the shelf" in nature and still maintain longevity and reliability while reducing lead times and costs?  I just found out that a project budgeted for last year was not started because of a 40A DC bkr has not yet been delivered even though it was ordered back in August.  The job is critical as it replaces a DC source that contractual terminated at the end of the year.  Why have million of dollars tied up in our warehouse for equipment that may or may not fail?  We want to be able to send our field personal to a local business that has what we need on their shelf for immediate purchase when something fails.  Not pay taxes on equipment sitting in a warehouse that eventually is just thrown away on the next warehouse cost reduction initiative.

RE: Relay & Control Panel Cost Reductions Project

3
jlgordon -
Sounds like an engineer's dream project in a lot of ways.  

Along with many other activities, I have been involved in designing/constructing P&C panels for many years.  My present "standard" design, distilling the experience of these years, centers around 19" rack accommodation of microprocessor relays.  A typical panel (41 rack units high) can accommodate two transmission line protections (duplicate distance protection - 138 kV in this case + metering), or two transformer protections (differential + overcurrents + metering).  This density saves considerable real estate.  Modular panels ease the assembly process and allow flexible mounting.
Standardized test switch facilities (again 19" rack mounted) and rail-mounted terminal blocks contribute to the increased density.  I have also worked with the "connectorized" removable wiring connectors offered by SEL, which replaces the conventional test switch concept.

I think that your cost savings will mainly result from minimizing wiring and space requirements - both areas where microrocessor relays will help.  

RE: Relay & Control Panel Cost Reductions Project

Peterb follows much of what I have found.  A lot of the cost is tied up in the wiring itself, and not so much on the hardware.  By using multi-function relays you can eliminate a lot of hardware AND potential for misoperations.  This will also dramatically reduce the hardware costs and wiring costs.

Use intelligent devices that can talk directly to the SCADA system.  This will eliminate most of your transducers and interposing relay panels.  You'll also get redundant readings for the same data points so you can cross-check the accuracy of data you're gathering.  Watch out for data overload doing this, as you'll be able to gather information you'd only dreamed about before.

I'd also look at your control switches.  Some utilities wire them into the RTU/PLC in the substation and not between the equipment in the substation.  Pros and cons to doing this.  Simplify the wiring as much as possible.

Mark in Utah

RE: Relay & Control Panel Cost Reductions Project

I would recommend SEL relays.  We have been able to eliminate transducers for SCADA, control switches, panel metering, reclosing cutoff switches, interposing relays etc. In addition all SEL relays and communications devices use the same protocol for communications.  The nice thing is that they do not require specific software to communicate with the relays.  You can use the SEL software or you can use Hyperterminal or Procomm and once you learn to talk to one, you can talk to all of them.  Only the settings change not the commands.  The Oscillography available in most of there units can even replace digital fault recorders, oscillographs, and sequence of events recorders.

Talk with them, they can save you a bundle and still provide the quality and reliability you are looking for.

RE: Relay & Control Panel Cost Reductions Project

  I've done a few of those jobs, the best way I have found is to have pre-engineered Panels built to replace the old ones. These panels only take up about a third of the room as your mech. relaying panels do. So you can plan your outage time around the wiring that is done to intergrate the new relaying and phase out the old panels a section at a time. Reducing the total outage time. The change over to Multi-function Relaying is a smart move, the relays that GE and SEL puts out are amoung the best. Learning the software is easier with the GE, but SEL has great tech support and more expertise in the field of multi-function line relaying.(SEL)= Schweitzer Engineering Laboratories. www.selinc.com

Electrical Power Solutions Ltd.
www.e-p-solutions.com

RE: Relay & Control Panel Cost Reductions Project

Have you thought of using web enabled interfaces, putting them on the Internet and looking at them with a browser? This seems to be the most inexpensive way of implementing a man machine interface in this century. . .
 You may care if the casual browser can see what's going on as long as they couldn't 'get at' anything (via programming passwords and so on).
If I were to design a modern SCADA system that is how I would do the MMI.

RE: Relay & Control Panel Cost Reductions Project

Whichever relays you choose to use, make sure the eng comms protocol is not a proprietary one. The cost of getting converters can be very high or impossible. Also consider what is needed to download / upload settings and records. Do you have to pay for the software?

RE: Relay & Control Panel Cost Reductions Project

A thought before you throw out that "100+" years of standards.  You are still going to have to deal with the "backbone" of the previous 100+ years at your existing and new installations: Cables.  While minuraturization and multiplexing of information has created opportunities and necessities for space reduction, I havn't seen any complimentary improvement regarding control cabling size reduction, routing, and termination requirements.  Conversly, I have seen an increase in the amount of cable terminations within a reduced termination space using reduced size terminal blocks.  This has been observed as a "glob" of wires with labeling that cannot be read or traced back to an entering cable or panel device.

RE: Relay & Control Panel Cost Reductions Project

Oh dear, 15 years ago I would have, and did agree with the management stance. "Let's move forward and invest in new technology" Now I would say why scrap a perfectly good backbone system. 70% of our network was re-populated with MIDOS relays. Now I am receiving obsolescent notices from Alstom nearly every week. So we invested in REF5xx series of relays. Over priced, over complicated, complex comms set up. Failures as long as my arm, two of which lost our whole system ! So now we are moving onto Siemans kit which seems to be a good direction to go. I hope....

When I walk into a sub and see an electromehanical relay I know its a) 25+ years old, b)reliable, c)repairable d)maintainable and doesn't cost me anything.

Think carefully and popoulate your system with new technology carefully.

PS The MICOM comms system doesn't work to the C922  I believe they have scrapped the i/f design.

I'd buy a large cork too......



RE: Relay & Control Panel Cost Reductions Project

There are new, costeffective, easy to use, with simple cooms set up, relays available on the market, no problem

RE: Relay & Control Panel Cost Reductions Project

(OP)
fb599, what you're describing is exactly my worst fears.  I am a big computer enthusiast from way back.  I know just how rapidly advances take place, where microprocessor are involved.  I also know what made some computer mnfs. successful and other not so successful.  What I hope to be able to do is lay out the foundation that will allow the protection schemes to change while minimizing, down time, costs, reliability, ect.  Today for example, when our utility upgrades an existing 64MVAR cap bank to 108MVAR, we wait until an outage is authorized and then we cut out a large hole in the relay panel where the Electro-mechanical relays were previously located.  Then a custom-made cover plate is installed with cutouts for the new microprocessor relays.  Finally, the new relays are installed and wired into the rest of the existing protection system.  The whole process takes weeks.

 This method is crude and time consuming.   The construction personnel do not enjoy cutting holes in the panels, as there are many traps to fall into.  The whole purpose of this thread is to look for a good way to allow for all the upcoming changes that are sure to come with advances in the power protection environment in the upcoming year, in as efficient manner as possible.

Over the last three decades, we have built several new substations using solid state or microprocessor relaying only to have catastrophic failures and / or a strong negative reaction from field personnel responsible for the operation and maintenance of our substations.  Valid arguments were always made in each case and we have always reverted back to the old tried and true method we are all so familiar with.  In several cases some very bright and innovative engineers have been forced to look for employment elsewhere. I think the key is to design a relay protection system that is functional, when initially installed, and has the ability to be changed as relays are discontinued. Preferably, without having to change out the whole protection system.  

I think the way a PC is upgraded is a key component to the success of specific companies and I feel that it is also a vital concept that can be used to manage the costs of upgrading our protection schemes.  How can we change a subset of a panel's protection scheme in the most efficient manner possible?  I don't want to have to throw away a whole, custom made, steel panel with every change in the future.  We had hoped that the rack mount panel would be the answer but those we have built, as of today, have not been acceptable for various, valid, reasons.  We are now looking at using  enclosures versus custom made steel panel or rack panels.  Hopefully, we will find the modular replacement stratagy, I think we need, and eliminate the concerns / fears of the operations personnel about the rack mount panels used in the past.

Oh yea,  I have to do all this for less money too!

RE: Relay & Control Panel Cost Reductions Project


At want point do you quit rerouting SIS wire and make all changes with flash-memory upgrades?
  

RE: Relay & Control Panel Cost Reductions Project

A couple of questions/points to fb599 & jlgordon's posts -

1. Where are you going to find the electromechanical relays to continue the "tried and true" methods into the 21st century?

2. Exactly how maintainable are these relays?  Yes, you can actually touch and feel the hardware and you can see the parts move, but what is the cost of keeping this equipment in service?  How much do you invest in training techs in this obsolete technology, and for how much longer?

3. In the mid 90's I completed a project that replaced a utility's electromechanical line protection schemes with microprocessor relays.  In most cases, we were able to spec relays that fitted in the existing cutouts, with blanking plates taking care of the numerous empty spaces left over.  Results were dramatic and are continuing - correct operations moved from 85% to 98%+ overall in the first year.  Calibration drift dropped to zero and test times were considerably reduced.  The fault location feature made instant admirers out of the operations personnel, whose line patrol efforts dropped considerably.  Fault recording and oscillographic data provided invaluable information for fault analysis and correlation for system calculations.

4. Rack mounting is without question the most flexible method of accommodating relay equipment.  I am familiar with large utilities that have used open racks for decades, with no adverse results.  If your environment requires an enclosure, then these are readily available.

5. I, too, have done my time with electromechanical relays during the course of the last 30+ years, so I feel qualified to comment.  The skill and ingenuity of the design engineers of the time are unquestioned, as evidenced by the wide variety and (mostly) reliable operation of the products that they produced.  Having said that, there is no way that I would consider specifying an electromechanical scheme in today's world, with the exception of single-function devices such as high impedance differential relays.

RE: Relay & Control Panel Cost Reductions Project

I'm interested in the comment made by fb599 concerning REFxxx relays, since we too have had problems with them (and I've heard of other utilities likewise). I gather they are prone to the software "locking up" and the relay simply stops working. However, they don't necessarily flag a watchdog to say so.

The Alstom C922 product has been withdrawn from the market - some problem with intellectual rights.

RE: Relay & Control Panel Cost Reductions Project

I would recommend SEL products as well.  I have been commissioning systems (up to 500 kV) and the SEL product continues to become more prevalent.  As another person mentined, once you learn 1 relay commands, you know all relays.  I would stay away from SCADA systems and utilize communications processors and relays.

The new UCA2.0 "Goose" communications standard will allow all manufactuers of relays transmit analog and digital logic and metering data.

SEL offers turn key solutions.  They build the panels, commission and provide a nice SCADA solution via wonderware.
Sel also can do the system study and most important the relay settings.

The biggest problem I have seen in the field is that "lazy engineers" do not take the time to understand the relay, do not apply the relay to the full potential and really screw up the settings.  Having SEL do this will save you immensely.

SEL also has the best quality.  In 2000, I commissioned 8 line (2 8 breaker ring bus+transformer+lines)

RE: Relay & Control Panel Cost Reductions Project

Although REF xxx relay is very powerful yet it's too complicated and not user friendly at all.In fact It's SEF functionality is flawed and can cause undesired operation.I invite readers comment and feed back on REFXXX relays.

RE: Relay & Control Panel Cost Reductions Project

I have watched this issue develop for almost 20 years.

Utilities and government installations in my area would not consider using anything but electromechanical relays until SEL came along, and for good reason. While electronic relays always had the potential of being more reliable, none that could meet "utility-grade" reliability requirements were made.

Now virtually all of the government or utility projects I see use SEL. Many of your responders suggest SEI in 19" racks. That is my current practice.

RE: Relay & Control Panel Cost Reductions Project

No. The issue is standardizaton of technology. Who starts it , how long does it last and who runs it to make sure that it lives. Apparently all technology has life 3- to 50 years. Later this may be dead but we want our products to be live. So the cost savings is in self training(organization have staff that will work for generations). and there will be pay off.
The products die due to aging. Have them designed for not aging or aging very slowly. Are materials available to achieve this goal. Yes they do exist.Do we use all the time -No - why we are mortals and like products to be mortal. So let us say people like you can change for good -better and best. keep it up and you will be there.
Thanks

RE: Relay & Control Panel Cost Reductions Project

What is the degree of protection used for the control & relay panels?

Are the control and relay panels situated in the same room?

RE: Relay & Control Panel Cost Reductions Project

I tend to agree that numeric relays in some form of  rack mounting is the way ahead.  But the major problem ahead is for the field staff - all those fancy relays, each with its own (unique) interface which will screw up[ your PC in a million subtle ways if you are not careful.

Like it or not, various forms of Wintel computers are pretty much the standard for driving the new relays, but virtually none of the programmers of the setting software have read and understood the Windows API documents.  Or they are the result of a merger of several manufacturers, and are still engaged in internecine warfare to see which brand predominates.

To cap it off, most of the relays are way to complex.  They do far too much for the average ues in distribution systems.  At least Alstom affer some goood simple relays - pity about S1 and the compromises between the 20, 30 and 40 series (from  UK (GEC?), Germany (AEG?) and France (Alstom?)).  SEL are the classical example - who needs 6 different definite time elements for 3 or 4 functions (neg seq, e/f, o/c etc) in 6 setting groups on a distribution system as in the 351A?

So I think the if I were to start with a clean slate, I would be looking for simple relays with simple interfaces that  do the job I want without having a whole heap of redundant stuff.  Flash RAM (bit failures) and electrolytic capacitors seem to be the weak areas in the relays we have used.  So be ready for them - have a good stock of spares on hand.  You will need a good firmware tracking system to  keep up with the ongoing firmware updates.  Be prepared to freeze relays at a particular firmware level ,as changes to frimware mean yo have a whole new relay on your hands.  Give your techs a brreak by limiting the nmber of different software packages they have to learn - stick to one or two manufacturers.

I could dribble on for hours, but I won't. TTFN

Bung
Life is non-linear...

RE: Relay & Control Panel Cost Reductions Project

Let's see... how many contacts do we need to clean on microprocessor-based relays? How many times do we need to do maintenance on mp-based relaying? Don't get in the trap of relying on any one manufacturer. For high-voltage protection we use two mfgs. relays.
Standardization of your panels and testing/installation procedures can help minimize costs and insure reliability.

RE: Relay & Control Panel Cost Reductions Project

I would suggest to take a look at http://www.vamp.fi I have gained great experience with these relays the last couple of years.  They have excelent specifications and are very user friendly.  The last project I done where two mobile substations (20" containers) 7 cubicles 24kV - 2500A complete with arc protection included.  Price was lower than the most "BIG" suppliers where asking to preform less.

good luck in youre quest

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