Overload relay difference between Manual mode and Automatic mode.

Hello everybody!

I have some doubts about overload-relays,
Siemens sirius overload relays have got a blue reset button which you can set-up on manual or automatic mode,
Lets assume that this overload relay are related with water pump and auxiliary contacts are connected to PCB,
In case of over-current:
When relay is set-up on automatic: relay will tripped and you will need to reset him(by hand)?
When relay is set-up on manual: relay will not tripped (even if current will extend set-up value on the relay)?
Am i right?
Or im wrong?
1594108463082.png
 
Hello everybody!

I have some doubts about overload-relays,
Siemens sirius overload relays have got a blue reset button which you can set-up on manual or automatic mode,
Lets assume that this overload relay are related with water pump and auxiliary contacts are connected to PCB,
In case of over-current:
When relay is set-up on automatic: relay will tripped and you will need to reset him(by hand)?
When relay is set-up on manual: relay will not tripped (even if current will extend set-up value on the relay)?
Am i right?
Or im wrong?
View attachment 361
Hello Andy1984

We would try to assist you, by First telling us the type /model of designed Sirius relay .

I got Thermal and electronic overload Sirius 3RU /3RB manuals.

I guess that the relay, which is shown on the picture is one of them.

Please clarify.

I strongly suggest you to see, product & operation description ( see web link as manual is too big for uploading here):
https://www.google.com/search?client=firefox-b-d&sxsrf=ALeKk03kKD9x5fiu-JzwVfF7C7SoOahuFQ:1594113909733&ei=dT8EX5G2LMbYaIW5jbgG&q=siemens+sirius+overload+relay+manual&oq=siemens+sirius+overload++manual&gs_lcp=CgZwc3ktYWIQARgAMgYIABAHEB46BAgAEEc6CAgAEAcQHhATUM7KI1jH1yNghucjaABwAXgAgAGoAYgBmwySAQQwLjEwmAEAoAEBqgEHZ3dzLXdpeg&sclient=psy-ab
There are mainly useful informations, on it to respond to these mentioned questions.

Hope this can help,
ControlsGuy25.
 
Hello ControlsGuy25,

Thanks for your reply & manual link!

Yes its about Siemens 3RU series,
I read this manual and its look that:
If i have got relay set on manual i need to reset this relay by hand,
And if i got relay set on automatic it will reset itself(and back to normal works after cool-down),

Maybe me thinking is wrong but for me "Automatic" means= i allow for automatic control of this element(relay) and if current will rise up relay will tripping and i will need to go there and push this reset blue button,
"Manual" means= relay will not tripped when current rise up(in other words: in manual mode relay is not active),
Im just wonder if somebody have "practice" with these relays and can confirm which is correct?
Apologize if this question is silly...
 
Hello ControlsGuy25,

Thanks for your reply & manual link!

Yes its about Siemens 3RU series,
I read this manual and its look that:
If i have got relay set on manual i need to reset this relay by hand,
And if i got relay set on automatic it will reset itself(and back to normal works after cool-down),

Maybe me thinking is wrong but for me "Automatic" means= i allow for automatic control of this element(relay) and if current will rise up relay will tripping and i will need to go there and push this reset blue button,
"Manual" means= relay will not tripped when current rise up(in other words: in manual mode relay is not active),
Im just wonder if somebody have "practice" with these relays and can confirm which is correct?
Apologize if this question is silly...
Hello Andy1984,

I think that you are thinking right and also after reading Sirius 3RU21 page 22&23 i can confirm it.
My only doubt is about your definition on manual reset .

For me Manual reset means that if fault/trip occur , relay will be reseted by locally ( in other words by hand ).
I guess its about equipment /human security, that you should choose between Manual or automatic reset mode, on kind overload relay.

Thats what I understood, after I have a good read on the manual.

It depend clearly about utility in process system that the RESET mode is selected ( Auto/Manu).
Hope this help ,
Controls guy 25.
 
Hi again ControlsGuy25 :)

"For me Manual reset means that if fault/trip occur , relay will be reseted by locally ( in other words by hand ). "
For me the "Manual reset" means exacly the same,

But im still not sure when i need to use "Manaul reset"?
In case when relay is set on Automatic? or in case when relay is set on Manual mode?
Regards,
Andy,
 
Hi again ControlsGuy25 :)

"For me Manual reset means that if fault/trip occur , relay will be reseted by locally ( in other words by hand ). "
For me the "Manual reset" means exacly the same,

But im still not sure when i need to use "Manaul reset"?
In case when relay is set on Automatic? or in case when relay is set on Manual mode?
Regards,
Andy,
Hi again Andy 1984,

As I mentionned before it depends, on how your process is operating .

You said that is dedicated to water pump?? right ?

Its about selectivity of protection process ( trip ).

You should study how the process/system behaviour is during transient periods/time.
I mean like inrush currents or overvoltage, load/thermal conditions .... (Motor cooling ) .

I suggest you to read this excellent article :
https://imcdirect.wordpress.com/2013/10/16/manual-versus-automatic-reset-on-overload-relays-which-is-better/

I am sure it can help you !
Controls Guy 25.
 
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