What does "upstream" and "downstream" mean in a circuit breaker?

[T_Parks]

Hello,

I have seen several times the words "upstream" and "downstream" related to circuit breakers. 

Can someone explain me simply and clearly what these mean?

Is there any difference with supply & load for circuit breaker?

Sorry if this question may seem a little weird to you .... 😊 😁

Thanks a lot.

[J_Travostino]

Hello @T_Parks 

Do not worry. There is no "stupid" question.

Someone from our community will surely be able to answer you on this..... 😉

[Anonymous user · Accepted solution]

Hello,

In Electrical Distribution, upstream and downstream refers to "Incoming" and "outgoing" circuit breakers.

Regarding your question on supply and load of circuit breaker, there is no supply side and load side in present circuit breakers 

and supply and load connections  can be reversed. In Earlier circuit breakers, there was specific marking on circuit breaker i.e.

terminals were marked with Supply or Load side, Technology has progressed and these connections can be reversed.

Hope I answer your question.

Thanks.

[T_Parks]

Thank you @Anonymous user for your quick answer. 

[Gregoire_Brun]

Hello @T_Parks  

On catalogue we speak about some limitation sometime about reverse feeding ( for some high perf breaker)

And we indicate on the breaker if it have limitation the "line" side for upstream and "load " side for downstream

[T_Parks]

Thank you @Gregoire_Brun for these complementary information.

What are the criteria for these limitations? 

Which products are concerned?

What do you mean "we indicate on the breaker"? I guess it is like some marking but can you confirm and eventually post a picture?

[RHH · Accepted solution]

Hello @T_Parks 

The breakers with those limitations have the indications on the devices.
Breakers who dont have this do not show this indication as it is not necessary.

As far as I know;

The breakers who can have these limitations are mostly breakers like;

An GFCI Circuit breaker - Ground-Fault circuit interruptor
An AFCI/D Circuit breaker - Arc-Fault circuit interruptor/detector

Why are those limitations especially on these breakers? Because they have an extra security build in where they have to react/trip/turn off to.

With this security in the products they are more susceptible to damage or fault-trips if they are connected reversed.

At last, the picture you ask about how it can be marked below;

Sometimes it is shown on a label on the breaker as well; No reverse feeding!

But like the previous answer; You barely see this anymore as the fabrication of breakers have evolved with the years.

Hope this is of any help to you!

[T_Parks]

Thank you @RHH for sharing information. 

[Gregoire_Brun · Accepted solution]

hello

It's due to some performance limitation in some products to respect performance during short circuit test.

It's the case for Compact NSX R, HB1, HB2 (690V application and the new NSX400K (1000V Application)

I will see to find some pictures to find equivalent picture shared by RHH-Eltechna

Best regards

[T_Parks]

Thanks @Gregoire_Brun