Fuse/Relay/Switch vs. Rocker & Circuit Breaker Panel

[bouyakasha]

Hi Team!
I'm putting together my electrical system, and was about to go down the tried and trusted route of installing a fuse box, then relay/switch systems for each of my components. But then I came across these Rocker & Circuit Breaker Switch Panels and got interested/confused.

Here is the rocker and circuit breaker box I was looking at on Amazon

Couple questions:

1. Do the circuit breakers in this act instead of fuses, thus removing their necessity from my system?
2. Actually, now that I think of it, does this item replace the need for fuses/relays? (and obviously it has switches)

thanks!

 

[Goldenraf]

Hi Bouyakasha,
The breakers are OK instead of fuses for low power circuits op to 15 Amps, as specified in the product. Enough to power lights, a DC refrigerator and so on. Better than fuses as they don't need to be replaced when a circuit trips.
However if you need a large amperage protection device, like for example the input of an inverter from a battery feed, you need to consider a fuse. Large capacity breakers are more expensive than fuses.
You cannot replace a relay with a breaker, there are 2 different things.

 

[bouyakasha]

Hi Bouyakasha,
The breakers are OK instead of fuses for low power circuits op to 15 Amps, as specified in the product. Enough to power lights, a DC refrigerator and so on. Better than fuses as they don't need to be replaced when a circuit trips.
However if you need a large amperage protection device, like for example the input of an inverter from a battery feed, you need to consider a fuse. Large capacity breakers are more expensive than fuses.
You cannot replace a relay with a breaker, there are 2 different things.

Thanks for your response!
Relays are used so that current doesn't need to run through the a switch, correct? That's the general purpose. So my question here is, is it appropriate to use these 15amp breakers to run current through?

 

[Goldenraf]

Yes, all you have to do is respect the maximum capacity of the breaker. Relays (or contactors) are used to switch high current charges instead of switches.

 

[bouyakasha]

Yes, all you have to do is respect the maximum capacity of the breaker. Relays (or contactors) are used to switch high current charges instead of switches.

Sweet! Well this looks like a great solution instead of wiring up a ton of Fuse/Relay/Toggle Switches!!! Cheaper and less time. Win win win!

 

[autostaretx]

Don't forget that the current that goes through relay contacts also wants to go through a fuse (or circuit breaker) for the protection against short circuits or overloads.

The relay is only there to allow you to use smaller (or longer) wires to the switch that you're flipping to turn whatever the relay is powering on and off.



The circuit breaker in the top diagram could be used as the switch, too. You don't need a separate switch.

--dick

 

[bouyakasha]

Don't forget that the current that goes through relay contacts also wants to go through a fuse (or circuit breaker) for the protection against short circuits or overloads.

The relay is only there to allow you to use smaller (or longer) wires to the switch that you're flipping to turn whatever the relay is powering on and off.

--dick (i may add a drawing in a few minutes)

Sorry, you lost me. I thought what was happening here is the circuit breaker built into each of these switches, thus no need for relays in this system. What you're talking about, if I understand you correctly, is the traditional fuse/relay/switch system I'm trying to replace with this panel. Sorry for the confusion...

 

[autostaretx]

Sorry, you lost me. I thought what was happening here is the circuit breaker built into each of these switches, thus no need for relays in this system. What you're talking about, if I understand you correctly, is the traditional fuse/relay/switch system I'm trying to replace with this panel. Sorry for the confusion...

I was trying to cover all the bases.
Yes, the panel you referenced has eight 15 amp circuit breakers.
Each switch turns one of those circuits on and off.
That's all you need if you're happy with all of your switches being in one spot, and if each load won't be over 15 amps.

The circuit breaker in the top diagram could be used as the switch, too. You don't need a separate switch.
Since you asked about relays too, it looked like it would help onlookers to show that relays alone are not circuit breakers, and still require protection of their loads.
The usual reason for relays (instead of just switches/breakers) is to allow remote switches (for instance, on the dashboard) to control heavy loads.

--dick (drawing now added to earlier post)

 

[bouyakasha]

I was trying to cover all the bases.
Yes, the panel you referenced has eight 15 amp circuit breakers.
Each switch turns one of those circuits on and off.

Since you asked about relays too, it looked like it would help onlookers to show that relays alone are not circuit breakers, and still require protection of their loads.
The usual reason for relays (instead of just switches/breakers) is to allow remote switches (for instance, on the dashboard) to control heavy loads.

--dick (drawing now added to earlier post)

Ahhhh! Got yah!

 

[avanti]

Not that you asked, but let me put in a good word for the usability of the approach you are considering. It is exactly what I did in our van:



The boat guys know what they are doing in using this style of switch. It is SO much easier to control systems and manage power consumption with a row of clear, easy to understand lighted switches than with stuff scattered all around the van. In our old van, the phrase "Dear, please turn on the inverter" met with a blank stare. Now, it is no problem at all.

Recommended.

 

[Goldenraf]

Not that you asked, but let me put in a good word for the usability of the approach you are considering. It is exactly what I did in our van:

View attachment 72264

The boat guys know what they are doing in using this style of switch. It is SO much easier to control systems and manage power consumption with a row of clear, easy to understand lighted switches than with stuff scattered all around the van. In our old van, the phrase "Dear, please turn on the inverter" met with a blank stare. Now, it is no problem at all.

Recommended.

I agree with Avanti. I had a sailboat before, I'm an electronic Engineer and I have been working with Power circuits and batteries since 1979 and it is extremely important to have a good plan a good installation by a professional electrician for your own safety. Avanti's picture shows such a setup.

 

[bouyakasha]

by a professional electrician for your own safety

Thanks for your concern. I respectfully disagree that this is always essential. I don't believe 12v installations do not, by default, require professional installation in all circumstances. Knowing what you're doing is important, but if all installations of this variety require professionals? I think that's going a bit far

 

[Goldenraf]

Yes Bouyakasha, it's not always essential, and I don't know your skills in the matter. I have seen over the years installations made by non professionals that were really good, mediocre or simply a public danger.
Just make sure you have the right tools and respect all the codes, remember you have an insurance in your vehicle!.
Good luck and don't hesitate to post for help in this forum.