Comments on adding a fuse box vs relays

What would be better?
Neither is better and it solely depends on the application. With low power requirements like a radio a fuse is all that is required but on high power applications like fog lights a relay is used otherwise you have to use large capacity wiring and switches to handle the loads.
 
I would not install a standalone USB charger. TJs came from the factory with a perfectly fine power supply, and my plug-in adaptor works perfectly.

A relay is not a circuit safety. If you are installing a relay in lieu of a fuse, I would suggest to do some research before working with electrical circuitry. This is not an argument or an insult, it is just a statement and a kind suggestion.
 
I would not install a standalone USB charger. TJs came from the factory with a perfectly fine power supply, and my plug-in adaptor works perfectly.

A relay is not a circuit safety. If you are installing a relay in lieu of a fuse, I would suggest to do some research before working with electrical circuitry. This is not an argument or an insult, it is just a statement and a kind suggestion.
Total double talk, I'll ask again would you install a .2 amp USB charger with a relay. Not talking about either or, just when to use a relay.
 
So if you were installing a .2 amp USB charger port you would add a relay ?
Short answer: No

I wouldn't even add a separate fuse but would rather tap into another interior circuit such as the cigarette lighter or radio power supply (which is already sufficiently over-sized and fused for 0.2A.

I will say that most USB chargers are not 0.2A - smaller ones are 1000mA (1A) and larger or "fast" chargers are 2.1A.
 
Total double talk, I'll ask again would you install a .2 amp USB charger with a relay. Not talking about either or, just when to use a relay.
If I was adding a .2 amp USB charger I would pull power from a non-important key-on fuse behind the glovebox with a fuse tap.
 
Yea I understand how both of these work. I just wanted to hear some opinions. What I am doing in my jeep is sort of both. I bought an additional fuse box and 6 relays for high amp products such as a light bar and so forth. Im going to have a 250 amp breaker from my battery to a fuse box. The relays will deal with the high amp stuff and the relays will be powered through the fuse box (they won’t be connected to the battery directly). Doing this will draw away the high amps from the fuse box and gear them more towards relays. Ask questions if this doesn’t make since.😂
 
A fuse interrupts a circuit in the event of an overload.
A relay is a powered switch.
These are different things with different functions.
I plug a USB charger into my already-fused power supply. Nearly every modern device that charges via USB has the ability to stop charging when a certain charge level is attained. You could say it is using an intelligent relay. You could say that there is already a relay in use.

It doesn't get more non-double speak than this, although I have already said it, so....

I have no additional input, and I will discuss these points no further.
 
Yea I understand how both of these work. I just wanted to hear some opinions. What I am doing in my jeep is sort of both. I bought an additional fuse box and 6 relays for high amp products such as a light bar and so forth. Im going to have a 250 amp breaker from my battery to a fuse box. The relays will deal with the high amp stuff and the relays will be powered through the fuse box (they won’t be connected to the battery directly). Doing this will draw away the high amps from the fuse box and gear them more towards relays. Ask questions if this doesn’t make since.😂
A 250 amp breaker for accessories is way excessive, unwarranted, and would protect nothing. If your light bar has LED lights, it barely draws enough amperes to warrant even a small relay. When you don't specifically need a relay for high amp devices, don't install one... they just add another point of failure.

There are only two high-current drawing devices on most TJs, the starter motor and winch and neither of those should be on a circuit breaker or fuse.
 
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Depends on the accessory but I've added both.

Heated seats--relay/fuse
Amp--fuse
OBA--relay/fuse
CB--fuse
Rocklights--fuse
 
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Yea I understand how both of these work. I just wanted to hear some opinions. What I am doing in my jeep is sort of both. I bought an additional fuse box and 6 relays for high amp products such as a light bar and so forth. Im going to have a 250 amp breaker from my battery to a fuse box. The relays will deal with the high amp stuff and the relays will be powered through the fuse box (they won’t be connected to the battery directly). Doing this will draw away the high amps from the fuse box and gear them more towards relays. Ask questions if this doesn’t make since.😂
250A breaker is huge and more than likely way, way oversized - meaning it won't work when needed.

There are only a handful of items that need a relay - high-draw lamps (note that most LED bars draw less than 8A nowadays), air-compressor, electric fan, etc. That said, I don't necessarily limit items of "high amp draw" to a relay however. There are instances where I don't want a lot of hot-wires coming through the firewall or where I want the device to power off with the ignition.

In these instances, I run a relatively low-amp circuit on a relay. A good example would be my windshield bracket lights. Currently they're 60W Hella bulbs. With both on, they're 120W or <9 Amps. While this technically won't gain much from going to a relay (especially after I swap them out for a set of KC LEDs), I don't have to worry about another 12 AWG wire coming through the firewall or another fuse-tap inside the cab. Since all my aux-switches on the dash are tied into an ignition-switched source, I have a high level of confidence that they will all turn off with the ignition switch.
 
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My thought process when I bought the relays were for future projects like winch and so forth. I said light bar just as an example. I plan to use fuses for all my leds. The breaker though is a different story I slipped up on tht one. And to the other people discussing the usb. Just tap into 12v socket… idk if you all were talking to me but I’m no idiot lol Ik how low amp stuff works that is why I’m adding a fuse box for my higher amp accessories to run on and to take some of the pressure off my stock one
 
I've taken to using these for most of my lighting needs.
1625884450193.png

If you're wiring 2 or 3 circuits, these are about as simple as you can get. You can attach them in a row if you are running several sets of lights to the front, with a common hot lead simply jumping from one to the next, or place a single for, say, auxiliary backup lights. If I had seen these 5 years ago when I was lighting up The Muddog, I would have used nothing but them.
on ebay.
 
My thought process when I bought the relays were for future projects like winch and so forth. I said light bar just as an example. I plan to use fuses for all my leds. The breaker though is a different story I slipped up on tht one. And to the other people discussing the usb. Just tap into 12v socket… idk if you all were talking to me but I’m no idiot lol Ik how low amp stuff works that is why I’m adding a fuse box for my higher amp accessories to run on and to take some of the pressure off my stock one
I don't understand the whole point of this thread? You posted a generic question, with no context. You get understandably obscure and not helpful information in response...Then get triggered because someone was making a point about a USB charger plug? If you know what to do...go do it. why the discussion?
 
I don't understand the whole point of this thread? You posted a generic question, with no context. You get understandably obscure and not helpful information in response...Then get triggered because someone was making a point about a USB charger plug? If you know what to do...go do it. why the discussion?
Never got rude once and I never said anything bout the usb … tht wasn’t directed towards me … so fuck off