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
RE: Protection relays
RE: Protection relays
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
https://www.linkedin.com/groups/Which-relay-brand-...
RE: Protection relays
But, ultimately it boils down to preference as long as you stay in the top tier.
RE: Protection relays
RE: Protection relays
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
RE: Protection relays
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
RE: Protection relays
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
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
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?
RE: Protection relays
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
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
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
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.
RE: Protection relays
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
RE: Protection relays
RE: Protection relays
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
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
RE: Protection relays
RE: Protection relays
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
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
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...
RE: Protection relays
RE: Protection relays
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
RE: Protection relays
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
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 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
RE: Protection relays
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
RE: Protection relays
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
RE: Protection relays
RE: Protection relays
RE: Protection relays
RE: Protection relays
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
Alan
The engineer's first problem in any design situation is to discover what the problem really is. Unk.
RE: Protection relays
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.