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Protection relays

Protection relays

Protection relays

(OP)
We are looking at upgrading some protection relays. We are looking at SEL, Siemens, ABB, Eaton....... Trying to determine who is the best? Looking for feedback. Any help would be greatly appreciated.

RE: Protection relays

Define 'best'? Most are reliable. What other features do you need / want?

RE: Protection relays

(OP)
Reliability, ease of use, drawout case, long term viability of the company, customer support, internal PLCs, wave form capture, comm protocals supported, self diagnostics... are few considerations I'm looking at.

RE: Protection relays

Best? Trying to start some sort of Religious War now are you? winky smile

One person's best is somebody else's piece of junk. And vice versa.

Who provides good support in your location? What relays are similar installations using in the area? What are you familiar with?

RE: Protection relays

(OP)
As of now we have two camps on site, one side like the Siemens 7sj6's and the other camp likes SEL. We have few strays that like the Basler and other misc relays. I've been reading a thread on linkedin and was hoping this forum could provide some feedback.

https://www.linkedin.com/groups/Which-relay-brand-...

RE: Protection relays

Personally, I like the SEL relays, but no drawout cases (and we don't miss them). If you're in North America you need to consider Siemens somewhat spotty record of trying to establish a presence, giving up, and then coming back to try again. Somebody that can do a decent job with all the relays you need will probably work out better in the long run than going with different manufacturers for different applications, even if you can find the "optimum" relay for each application. Gaining a good knowledge of the quirks of a single manufacturer's products will serve you better than having to keep up with multiple manufacturers.

But, ultimately it boils down to preference as long as you stay in the top tier.

RE: Protection relays

If you are in the USA, it's hard to come up with a recommendation other than SEL due to their customer support and warranty. I agree with David that there are benefits to sticking with a single supplier as much as possible. As a consultant, I've had to learn how to configure and program a lot of different relays and the learning curve can be steep and time-consuming. Recently had to configure an ABB RER reclosing relay and it was a PITA to learn a completely new product - much different than older ABB relays I have dealt with.

RE: Protection relays

Alstom's relays are capable but they can be a pig to program and the manuals are awful, not for lack of detail but for sheer overload of obscure and esoteric information while omitting or hiding the more commonplace stuff. The old Areva relay business split in the last few years with the more basic relays going to Schneider and the top-of-the-line going back to Alstom. I don't personally think Schneider will keep the range in the long term as they already have the SEPAM series, and I expect Alstom will soon develop their own basic relays to plug the gaps in the ranks.

GE's larger stuff was decent to work as I recall, the G60 / T60 era. Their offering was more geared toward generating plant than transmission and distribution in my opinion, but if that's your line of business then they might fit the bill.

ABB's newer line isn't as well-finished as the older stuff from Baden, given the massive improvements in computing power and the advent of the GUI since the days of the RE*216 series. There are glitches and quirks which should have been resolved before it ever saw the outside world.

Nothing against the Siemens relays, other than they are quite unforgiving in terms of configuration. If you do everything correctly, in the correct sequence, they are fine. Damned expensive too as I recall, at least in the UK.

RE: Protection relays

Another good point for SEL is the economical one.

RE: Protection relays

I don't think there is a guage to measure service, and dependibility. It's more look at manuals, and ask about service from sales reps. Some are better than others.

But my first clue would be to look at the manuals and see about the readability. Some are really bad, and some have been translated quite well. And some assume you have a PHD to be able to read them.

Service and assistance is another factor to look at. The local sales rep. might be bad, but the company might be quite good, or the other way around.

RE: Protection relays

What are you upgrading from and why are you upgrading would be key factors.

RE: Protection relays

I had a job offer from Siemens on being the protection relay guy for the west coast. I thought their market share, for the entire US, was pathetic and the lack of people who can service / support them is reflected in that. When I went to work for a different division of Siemens, I would keep getting calls from desperate customers wanting help on relays and getting frustrated trying to get answers.

For the most part I like SEL too, they are very highly reliable and the company is first class. I've used a lot of GE / Multilin too, nothing wrong with them either, but their sales channel strategy flips and flops back and forth too much for me. They used to market through very knowledgeable reps when they were Multilin, then they decided I had to buy from Gexpro (the old GE Supply), who were completely useless. Now they are doing both, but the reps are no longer very motivated because they lose all the big orders to Gexpro. Kind of sad really, the Multilin guys taught me a lot about protection relays in their day. I think SEL has picked up on that and stepped up their game on support to take advantage.


"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington

RE: Protection relays

I agree, using only SEL products is the only way to. Their manuals, programing, start-up and esae of monitoring and controlling with A-B plc SCADA are all first class. Good support from sales also.

Two years ago, I switched out a double ended 138kv/34.5kv, 250MW substation for a steel mill with two arc furnaces and several rolling mills from electo-mech relays to SEL ones.

The 138kv bus is normally open, but the utility gives a $10,000 discount/month for them to tie them together. That saves them building another line. There where two utilities and now there is only one. Also on the 34.5kv side is bedirectional for feeding us or we feeding them one or both lines. The breakers have 2 sets of trip setting and the revenue metering started out to be a real mess, but after reading the manuals it was fairly easy.

Removed all of the old relays and panels and was up and running in 22 hours. I was allowed no more then 48 hours, so I looked good to my boss. Now we are switching out all of the old metering by the end of 2015.

RE: Protection relays

"I agree, using only SEL products is the only way to."

Maybe in the US. There's a place called "the rest of the world" where SEL have little presence and where the old-established European brands dominate. That might be a factor to consider? smile

RE: Protection relays

I have used SEL, and they're fine, probably one of the best. I think GE's Multilin family of UR "Universal Relays", which are designed on a modular platform, are interesting...especially with the hard-fiber process bus "brick". The brick is a remote I/O device that would mount in substation equipment, say in a circuit breaker cabinet, that uses IEC 61850 GOOSE messaging. IEC 61850 is probably what everyone will be using sooner than later for a protocol. It's an advanced protocol developed specifically for utility applications and reduces time spent mapping registers or "objects" by doing it almost automatically.

The GE brick is a remote I/O interface where even CT and PT inputs can be plugged into it, and the UR's simply sample the signals at their own internal clocks. No other protective relay manufacturer has a remote I/O device like this, of which I know, on the market right now. The brick can significantly reduce copper wiring in the substation yard, replacing copper control and instrument cables with fiber optic cables that are immune to EMI. One can even use redundant bricks, have primary and backup relays on their own brick and have those two bricks "talk" to each other; then one can shift the backup on the primary brick if that secondary brick fails or if it's being serviced. ABB has something similar to this called a "merging unit", but I don't know if they have it widely available, yet. GE Multilin makes relays for nearly all applications, not just power plants. It's just that many companies use them for plant applications. However, I see no reason why they couldn't be used on an entire transmission system, again, as Multilin has relays for about every application including buses that could use dynamic zone protection. They even have transmission line relays (directional distance, mho or quadilateral characteristics or pilot relaying).

I would seriously look into the GE brick. It would all but eliminate copper control and instrumentation cables in the substation yard. Really you'd only have to run DC power to the brick and that's it....of course you'd have to run power to the breakers, transformers, etc. Programming probably wouldn't be that bad, too...probably about the same as using conventional I/O on the back of a numerical SEL relay, except it would all be via GOOSE messaging. I think the brick takes advantage of IEC 61850 very well. Some people may be hesitant to use this because important I/O, including tripping outputs, for the relays wouldn't be hardwired to the relay; relying instead upon a communications channel. However, I've not heard bad things about the reliability of IEC 61850 or the GE brick. Also, the brick is environmentally hardened and the fiber cables running to the brick are rugged and even have a rodent barrier built into them. Also, it seems more utilities are turning toward IEC 61850 for protective relaying applications. So, if you're uncomfortable with the idea of using a comms channel for crucial I/O, I'd probably go with SEL or GE. Either are better than most other manufacturers out there for either plant or transmission relaying, with good support and customer service....SEL's support and customer service might be better than Multilin's.

RE: Protection relays

In North America, SEL relays are a good choice. They are economical and work well.

We have experienced terrible reliability of GE products the last while. We even had every GE relay fail multiple times at one site.

RE: Protection relays

Scotty, In the US it is hard to get good service from most equipment manufacturers. The brands from over seas tend to be very light on support, and very limited stock in the US. Also service tends to be on eastern time. I also have the same complaint with many US manufactures, in that they are mainly on eastern time.

Many of us in the West really don't like having customer service only from 8 Am to 2 Pm, and none available for a week after a snow storm.

SEL is located in the west and has customer service from 9Am to 6Pm, and is available after a snow storm. And they have a sales and service person, in addition to a service engineer a hour away from here.

I think most new inventions that are good will spread across the industry as soon the patent wears off, and if the brick really is a good idea it will be the same way. I just don't care for the GE sales staff, so I don't try any of there products.

RE: Protection relays

I would really like to have a play with one of the SEL relays just to see how good they are. A lot of people on this forum whose opinions I trust speak highly of them.

We could probably get hold of them as an import but I think it would be hard to handle in terms of support. I wonder if SEL have ever tried to break into the European market? It is such a small 'c' conservative industry that I think it would be tough for a newcomer even if they were exceptional, but it would be nice to see someone challenge Alstom's dominance and maybe teach them how to write user-friendly manuals. smile

RE: Protection relays

Scotty,

Just out of curiosity, I looked on the SEL website and they do list a Customer Support person and Protection specialist in the UK. I'm guessing they might loan you a relay to evaluate. Our local support engineer has an entire rack full of relays (at home) that he uses for support purposes.

Cheers,

Dave

RE: Protection relays

SEL has an office in "Stafford ST16 2RH". More details are available from the SEL web site. They have some presence (sold at least one unit) throughout most of the world, but are certainly strongest in North America. Manuals are all available on line once you register with SEL.

RE: Protection relays

For my province we stick strictly to GE and SEL for most of our subs. I'd say whatever is used most in your industry as swapping relays between buildings in a bind comes in handy as well as your supplier would have the relays more readily available.

RE: Protection relays

Scotty, you would see some things like when we read a manual written in British English. A little different, as I don't believe SEL has any manuals in anything other than American English. But they can be difficult to read for the first time (it is hard for me to tell as I have seen so many of them).

Start with a simple relay manual like the 551, to get the terminalogy, befor moving on to the more complicated relays (wish someone had told me that years ago). Although I assume other relays manufacturers are the same way.

Beware there are a few quarks, and some real difficult relays in there line up.

Maybe someone needs to develop a list of starter relays for young, and older, engineers to develop there understanding of manufacturers logic upon.

RE: Protection relays

Make mix.
SEL with ABB, Siemens with GE, Beckwith with SE.
it will be interesting.
btw, we make line protection with REL650 as 21 and SEL311 as 87L.
In one project, Im used SEL2506, nice device

RE: Protection relays

In Stafford? That's the home of GEC's St. Leonards works... lol That can't be just coincidence. I wonder if their rep is an ex-GEC or ex-Alstom employee? I may do some more digging, although it would be hard to justify moving away from our installed base of Alstom relays without some fairly massive benefit. Thanks for the heads-up David.

RE: Protection relays

"Hard to justify moving away..."

The way I put it is that we'll be using SEL relays until SEL forces us to make a change. I just can't see somebody else coming out with something so much better than what we're presently using to make the pain of changing worth while. And it would be a huge pain, pain for the protection engineers, pain for the relay techs, pain for the substation design engineers, bah. So, it's real easy to see why somebody else would want to stick with what they've already got installed.

RE: Protection relays

David, what did you use before SEL? Why did you change?

Yea I know where you worked before.

There was a reason many of us switched to SEL.
I tried Alstom relays years ago, because of one of there sales engineers. They weren't bad, but the tech's hated them, except for the bus diff. relays.

RE: Protection relays

Hi Cranky -

I find Alstom's relays are technically very capable and must be designed by some very smart people. The techs probably hate them because the manuals make them hard to commission, especially for the more sophisticated functions. I've been in this game a little while and I find the manuals are very hard work. My techs feel the same. Personally I hate the programmable logic editor for the Px4x relays because it is incapable of doing anything tidily. Nothing aligns, and nothing can be forced to align. It wouldn't have taken much effort to make it a good editor, and that's very frustrating. Visually it makes my work look like crap which bugs the hell out of me because I do take some pride in making drawings presentable. I have to make my own work look half-decent because I frequently send contractor's work back covered in red pen if it is untidy or badly presented: let he who casts the first stone and all that biblical stuff... winky smile

RE: Protection relays

The SEL decision here was made long before I started. When, in the late 80's, it was time to do something other than the HZ or KD as line protection the early SEL relays were one of a few different things that were tried. We still have a bunch of SEL-121G relays and have only a very few other examples of the other things that were tried. By the time they moved onto the SEL-221G there was no looking back as far as transmission protection was concerned. It took longer to decide that brand-x distribution relays weren't worth the effort (at least a couple of different brand-x labels).

RE: Protection relays

It's true that the manuals must be very difficult to write. I think what was some of the bother with the Alstom maunals was one manual for several different relays. And if the truth be known, the only difference in the relay models might have been the programming. But the manuals should have been for the specific model of relay.

Some of the other things were the size of the manual, and the unfimularty with the symbols in the manual.

I think they liked the bus diff. relays because they were simple electromechinical, and very small because the MOV's were not in the same case as the relay. The MOV's could be placed at the bottom of the panel, in the area that one would not typically want to place much else.

Some of the SEL manuals are also difficult to read, and what comes to mind is the 387 manual and the difficulty I am having with consultants and the trip equasions. The issue is the method eluded to in the manual will not produce the correct phase targets on the relay (It displays all three phases). And while it makes little difference which phase on a three phase transformer is faulted, the people in operations want to see them (I'm guessing they want to over analize the problem).

I know stupid issue.

RE: Protection relays

(OP)
Appreciate all the replies.

RE: Protection relays

I have adopted SEL only for our system.

Their customer support is absolutely the best of any company I have dealt with and I have been in this field since 1975.

You should seriously consider their high-interrupting capacity output contacts for your trip outputs.

On our system we had several cases of older medium voltage air-magnetic breakers opening slowly and melting the Basler relay output contacts which are not rated to interrupt trip coil current.

Relays had to be replaced and obviousy we went to work on breaker maintenance, and in the end upgraded all of them to new vacuum breakers.

But if this happens in the future, the high capacity contacts will save a relay replacement.

RE: Protection relays

Hi all,

In the couple of minutes I have read a really nice discussion that you composed here.

wolfie1a, can you tell us what is the application where you want to upgrade relays? I could help you with an advice for appropriate SEL relay and arrange to loan the SEL device.

RE: Protection relays

I'll throw in my $0.02 about SEL relays.

I like them. Have dealt with them for 20 years. I started with SEL, so I'm familiar with them. All positives about service, support, in my experience are all true. I have also found the pricing to be more than competitive.

The only thing (as a commissioning guy), that drives me nuts is how things can change from relay to relay - series to series.

Example would be naming conventions for 51 (51P / 51S) elements. Commands used in the terminal mode to accomplish the same thing. Opto Inputs that on some models that look like a coil (voltage testing wise) and others that appear open (high impedance).

With all of that said, I am on a project where there are 20 year old SEL relays used for bus protection, while the feeders are still EM. We had a feeder lock out the other day. Via smart programming of the bus relay (extra OC elements used to trigger event reports), I was able to plug into the 1994 relay (and settings) to help the customer identify phase of fault (relay trigger an event). Additionally SEL relays can always communicate via a terminal emulator program (Hyperterminal, etc) to access settings, SER, history - everything. There are better ways to do this, but this method always works.

I have had experiences with other brand relays, where there was a program for settings, one for logic, one for event reports. It was old 16 bit stuff and if not installed in the correct order, nothing worked. Many still keep an old, separate computer with these programs installed, just for these reasons. The terminal emulator rule was a well though out idea 30 years ago.

RE: Protection relays

DTR - interesting comments. The fact that everything that needs to go to the relay or come from the relay can be in text format is very useful. We have developed a setting process (presently in excel, being rewritten in VB) that produces a text file that makes its way to the relay without further human editing. That eliminates a lot of places where things can go wrong between setting development and settings in service in the relay. But every time they change the name of something we get a bunch of errors when the old setting names aren't recognized by the new version of the relay. It would also be nice if they'd gone with the C37.2 definitions of N and G, but oh, well, life goes on. But the support is great and the product warranty can't be beat.

RE: Protection relays

I will add another feature of the SEL relays that I find very useful in commissioning and relay testing.

SEL calls it a "Relay Word Bit". It is a logical element in the relay (an input (IN101), an ouput (Out101, TRip, 51PT, 32QF, etc). If the relay word bit is listed in the book, this can be displayed logically (show me this bit "n" times in the terminal display), or freely mapped to a contact output, or displayed via an LED.

Testing procedures for EM relays often called for blocking a contact open or closed (with a $20 bill to remember to remove). A SEL relay can be programmed to act a same way (via an unused output contact (Testing)), to either replicate existing testing standards / procedures, or for troubleshooting & commissioning, keeping the main tripping contact logic intact. This is extremely useful when trying to get ones head around the logic of both the relay algorithm and the settings applied. I have found that for both expediency and clarity, being able to "see" what the relay sees is very useful.

One further note about SEL relays and instruction books. In the SEL 251 series instruction manuals, there is an application note on how using both a bus and feeder arrangement of relays (via different setting group selections), a bus and feeders can be protected for a failure of a feeder relay (via 2 sets of self fail alarm contacts), can tell the bus back up relay there is a failure (change settings and become more sensitive) and via Aux relays and wiring (no more complicated than a lock out relay scheme), to trip the feeder (and only that feeder) that has a failed relay. With additional wiring to this scheme (a "Feeder Relay in Test Mode" Switch, this also allows for feeder relay testing / maintenance while still providing adequate protection with the feeder in service. I commissioned one of these schemes, as outlined in the SEL 251 manual when I was still a greenhorn. Years, later I see the beauty of this as it also allows the maintenance of a feeder relay in service. This scheme could be applied to any digital relay with proper design (and 2 alarm outputs).

As has been mentioned earlier, if one has not been exposed to a SEL relay, it can at first seem intimidating. When written out, it is an Algebraic math argument (TR = 51PT +(OR) 51GT *! (AND NOT) 50L). Algebraic order of operation matters.

I've seen the GE Brick system and challenged a qualified GE applications engineer to really show me how it works. It does and the hardware for the brick (ADC - 61850) is very robust, the fiber patch system is logical, etc. GR UR series relays do have some very compelling features. I think with a brick type solution, for example, it would be possible to add 87B (Bus Diff) to nearly any circuit and that would help to solve the arc flash problems for many.

At least here in the USA, there is still a reluctance to take that next step. One reason may be that when a mis-operation occurs, there is hell to pay for the folks in the field (and others Im sure). With current technology (non 61850), we have test and isolation switches that are (hopefully) available to make checks for trip signals, volts, amps, etc. On a new project where everything could be tested via primary injection, confidence could be gained. On upgrade/brownfield projects, where it is a 40+ year old station (with old, unreliable drawings) this could be a problem. If, for example we already have issues with settings and drawings now, how about with a non standard implementation of 61850 that was not well documented ( in the field) 40 years from now.

Watt and Var consumption (mostly real power) has occured

RE: Protection relays

As great as SEL is, I do wish their manuals were (substantially) less than 500 pages. Being on the troubleshooting side of things, we only look at these during panic outages. smile

RE: Protection relays

The only things I don't like about SEL relays are that Compass the autoupdater is terrible, too many differences in terms and operations among the different kinds of relays, and too much flexibility for the user. Most applications don't require the amount of depth that the relays offer and this leads to the possibility of mistakes being made. I think the SEL-411L has an option of blocking off portions of the relay that are not going to be used based on the (basic, medium, or advanced use setting). The relay should only as complicated as it needs to be because a tech or another engineer will have to review and modify your settings at one point.

The most stupid thing that I came across in their relays though was the non-explicit output that is dedicated fast differential tripping on one of the differential relays. Instead of showing explicitly in ACCelerator that the fast trip bit is OR'ed with whatever logic you have in place for that output, you only come across this when going through your manual. The relays are great but most misoperations are due to bad settings. SEL's goal should be to only make the relays as complicated as necessary. They have a template maker thing you can buy, I haven't used that but maybe that would help.

RE: Protection relays

While I can feel your pain, I completely disagree with the bit about "too much flexibility". I wish their default settings were everything off so that the user didn't have to go through and turn everything off before building from there, but I wouldn't want to have to deal with more versions of the relays than already exist. We have our own "template" process for developing line relay settings with the goal of applying one set of standards to a variety of relays; the SEL templates (which they aren't pushing nearly as much as they used to) are specific to one firmware version. That makes it even worse in my opinion.

RE: Protection relays

(OP)
A few have asked what we are doing and why. I have a couple of 15KV to 4160 subs we are looking at upgrading the relay along with adding a remote open/close feature. I think the subs are 20 to 25 years old. The relays 50/51, 51GS and 87T’s are no longer manufactured or supported. We are hoping we can spec out relay that has multiple function, using the same software, easy to program and test with a good 10 to 15 years of service support. We have done some brainstorming in house as to what we want in a relay and weighted each feature. Hopefully as we go thru our relay evaluation we can determine if one mfg has advantages over the other. The open/close feature will probably be a touch screen mounted outside the arc flash zone allowing us to safely operate the breakers.

RE: Protection relays

51GS - inverse overcurrent of some form. I hate guessing, especially when there is so little standardisation on use of suffix letters. Ground? Generator? Stator? Standby? Secondary?

RE: Protection relays

(OP)
Should have mentioned it a high resistance grounded system. The 51GS is the ground fault on the feeder breaker. The ground fault will immediately notify the operators and electrical staff that we have a ground fault and we also start a timer if the problem is not corrected within that time period we trip the feeder.

RE: Protection relays

wolfie1a

Based on your needs, you could look into
SEL 500 series (587 (Diff & O/C) & 501 (OC - dual) - Low Cost -minimal, but proven platform, or
SEL 300 (387 (Diff+O/C +++) - modern platform (higher priced) & SEL 351 (19" relays) Fixed (but available expanded I/O) or
SEL 700 (787 (Diff & OC) + 751A (O/C++) lower cost, more comm options, expandable I/O. Programmable Push buttions

I tend to think for the size and application you are seeking, the SEL 700 series is a good choice, as the I/O can be expanded, the communications options (past and future) are available and it fits into a panel cut out roughly the size of old GE & Westinghouse 50/51 relays.

The SEL 500 series are a bit older technology and have limited I/O.

SEL 700 uses the green "Phoenix" removable connectors (some like, others dont). SEL 300 / 500 series can accept a standard #12 AWG ring type lug.

SEL has on their website "Retail" Prices, and on line configuring (which updates the pricing).

Please don't forget test switches, whatever you do!!

RE: Protection relays

I have nothing but good experiences with SEL. The manuals are extensive and there is a learning curve to be sure. Their application engineers are knowledgeable and responsive. Field support is great also. Nearly everyone I know who works there likes the company and a couple have tried to recruit me.

Alan
The engineer's first problem in any design situation is to discover what the problem really is. Unk.

RE: Protection relays

A relay with GE's design concepts, Alstom's hardware design, SEL's reliability, Basler's software and Schneider's service would be close to prefect for me.

But good product support is most important of all. In my part of the world ABB and Siemens are really bad at this, so I would steer clear of them, but I imagine in parts of Europe their support would be very good.

The catch is you need to be selling relays to be able to fund good local support.

Finding out what other companies in your region use will give you a pretty good idea as to which ones have good support.

They all have good features, along with problems and strange quirks.

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