SEL311L, help. 4

[slavag]

Dear Friends.
Sorry for such kind of Q's.
I must connect SEL311L in my application, its decided today before few hours.
We don't have any expirience with SEL, we don't have any local support.
Setting, software, commissioning, no problem, we have enough time.

I need urgently few issues.

CT data, according to manual.
1. 150>=(X/R+1) x If x Zb
2. 20>= (X/R+1) x If x Zb ( for avoid CT saturation entriely).
3. 7.5 times worse, than the case which avoid all CT satuaration.

I calculated my CT before, for another relay with 21 with 79.
My chioce was class PX Vk=1500V, Rct<=4Ohm.

X/R=40, 63kA, CT: 3000/1A.
that means If=21, 41x21>>>>>150.
What is a point???

Next issue.
OUT107 can operated as extra alarm.
What means? Its LIVE-CONTACT, Im not found any data about live-contact or WD contact or Internal relaya fault contact.

Next issue, according to my understanding, all inputs and outputs of SEL311L if free programmable. Its true?

My problem is re-design of protection cubicle, all was ready for another relay, and next week need start mnf. of cubicle.

Thanks in advance.
Best Regards.
Slava

 

[davidbeach]

SEL has very good field support, contact them.

In your saturation calculation, Zb should be a number well less than 1.

Not quite sure what you mean by LIVE-CONTACT.

Other than the dedicated ALARM contact, all 100 and 300 series INPUTS and OUTPUT on the 311L are fully programmable. The 200 series OUTPUT contacts (no 200 series inputs) automatically become differential trip outputs if high speed tripping is enabled.

 

[slavag]

David, thanks a lot.
I meant, some contact is indicated about internal fault of relay: power supply, CPU, AD converter, etc..

 

[davidbeach]

The alarm contact is generally a normally closed contact that the relay holds open when powered up and all is well. Closed contact = trouble.

The relay can also be ordered with the alarm contact normally open with the relay holding it closed when powered up and all is well. Loss of continuity = trouble. We used to do the first, now do the second.

I haven't verified, but if OUT107 truly can be a second alarm contact, it would work the same as alarm.

 

[DiscoP]

We have used other SEL3** series relays, with them OUT107 can be configured as a second alarm - I guess the 311L would be the same (but have never used that type)

You need to change an internal jumper to make it an alarm contact.

Then a different link to make it a N/C alarm contact.

From memory, the n/c contact link needs some soldering work.

It should all be detailed in the manual.

 

[stevenal]

"Next issue, according to my understanding, all inputs and outputs of SEL311L if free programmable. Its true?"

Almost. The alarm contact cannot be reprogrammed, but the other outputs can be. If you wish to repeat the alarm condition on output 107, assign relay word bit ALARM to that output. Analog inputs cannot be reassigned, but digital inputs can be used in logic equations however you like.

 

[slavag]

Thanks a lot to all.
I used repeat relay for alarm, OUT107 used for another information.

I finished today re-design of line protection cubicle and sent drw's to customer approval and mnf..

SEL311L used as 87L only, w/o any additional functionality in this application.

Interconnection with other relay ( ABB REL670) will be intreseted, but commissioning will be in the next year .

 

[DTR2011]

I'm not so sure that the SEL 311L will properly communicate with the ABB relay. If I'm not mistaken, SEL 311L uses a proprietary communications protocol for the 87L function. I would strongly suggest you verify this with both ABB and SEL.

The SEL 311L uses the "Alpha Plane", for its restraint characteristic, which is significantly different from a traditional operate / bias characteristic, which I believe the ABB REL 670 relay uses. My gut feeling is that this 87L system with mis-matched relays will simply not work for these two relays and 87L. The SEL 311L has documentation on what the Alpha Plane looks like and the mathematical equations defining it.

I have commissioned about 30 311L systems and it has always been SEL 311L to SEL 311L. If you were using the 21 function and a Pilot scheme, that is a different condition and is simply coordinating the input / output contacts and coordinating the delays / response time between the relays. Always with two different relay systems, end to end tests.

There are SEL offices in Europe, as said before, SEL has excellent customer support engineers and will get you correct answers either immediately or very quickly.

The SEL is a great relay and very flexible. Once you get used to how it works, you will love its flexibility. I remember getting ABB training for REL 511 in Sweden and the SW / system was so foreign to me I simply could not understand so many different SW required for the relay and the dependence on having to rely on ABB for logic schemes and the difficulty in programming the scheme / setting, etc. I suppose it is what you are used to and how much you use it. I have played around with REL 670 and things have improved significantly since 2003 and REL 511.

Good luck!

 

[slavag]

Thanks smallgreek.
No, no, on other side of line is SEL311L too, of course.

REL670 will used for 21, 25 ( for 1-ph autoreclosere), 67N only

for 21 used PUTT or POTT ( depend on utility decition)via SEL311L and Focus (Pulsar)
for 67N used blocking scheme via SEL311L and Focus (Pulsar)
DTT (direct transfer trip) via SEL31L and Focus (Pulsar)
All fiber optic connection via two ways.

For autoreclosere will used REL670 with signalistation from SEL311L.

Of course all conectiona between REL670 and SEL311L are via dry contact only.

BTW, SEL311L is not included 67N

 

[davidbeach]

You realize, of course, that the 311L can do all of the things mentioned, 21, 25, 67N, 79 etc. Two 311Ls make a complete line terminal; easily for single breaker applications and with a bit more complexity for dual breaker applications.

 

[slavag]

David, no problem, for me is not important , I work for my customer. Is not something against SEL311L .
But, according to the manual, 67N is not included in the relay.
67 yes, ground distance protection yes, included.
please see attached.
My customer request for 67N connection of brocken delta VT configuration and not approve me used 3U0 internal calculation.

for 25, SEL311L have only one BB VT input, but I have double BB configuration, that menas I have build external logic with disconnector dinamyc replica, etc...

From other hand, it is my first SEL, will see .

Thanks again for your help.

 

[davidbeach]

For two breakers and two SEL-311Ls (or 311L/311C), each relay does synch check across one breaker and provides a supervisory output for that breaker that controls the other relay closing that breaker.

If they require 67N to use measured 3V0 rather than calculated 3V0, why not just continue to use electromechanical relays?

 

[slavag]

I do not know, what is a reason of this request.
Fot lot of years, we'e used calculated 3U0 and 3I0 for this company.
I think, reason is possible fault in the voltage circuit. In this case will blocked both 21 and 67N.

BTW, for my understanding:
I see not used terminals Z, are it for some optional current inputs, for stub protection?
and next Q's, sorry again for Q's, are distance phase elements is Mho only?

 

[davidbeach]

I'm not aware of Z15-Z24 ever being used.

Phase distance is mho only. Quad phase available in the 421 and 411L.

 

[stevenal]

67N is included. Simply use relay word bit 32GF or 32GR to torque control your ground overcurrent elements.

 

[slavag]

Yep, I would prefer used in my application SEL411L, 5U variant with additional I/0 boards. But it is not depend on me.
SEL411L is classical solution in such application: 500kV generation line, double bus or one and half configuration.