Fuse taps using the hot side aka wrong side

Rajagra

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#61
I give up on the orientation of fuse taps..:).. Just.. because you have found a colored image does not make it correct.
Nigel's image is correct. Due to it being an accurate schematic, nothing to do with the colouring. :cool:
The only thing you could dispute is the wording. "Correct" vs "wrong" way round might be more objectively worded safer/less safe. They are different, the less safe version might even have an application if you check the wire rating.
But the safer version is more proper, and should be the default choice unless you have a valid reason to go the other way.
 

Ralph2

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#62
What this forum needs is a "beating a dead horse" smiley. But.. I still beg to differ with your interpretation of correct. The "add a fuse" is used because there is not an available slot. But.. consider the wiring if there was. From the hot side.. through the fuse.. to the application. That.. is how every fuse in the fuse panel works. In fact the whole fuse panel is an application of "add a fuse" as there is a circuit breaker (or fuse) feeding it.
If.. you want to mimic the way the engineers designed it you will place the new add a fuse one way, source from the main buss.. through the fuse.. and to the application. "Your" way takes the source "through" the original fuse.
 

Rajagra

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#63
If the fuse box is fed by a single, monster cable - and it may well be - then that would eliminate the potential problem. Provided there were no weak links inside the fuse box (thinner wires, circuit board traces, or whatever. Or even the fuse sockets themselves.)

Edit> Another thought - anything that goes through a relay, like switched accessory power, must not exceed the relay's capability. Adding any circuit that isn't fed through existing fuses could do so.
 
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Nigel

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#64
In fact the whole fuse panel is an application of "add a fuse" as there is a circuit breaker (or fuse) feeding it.
I think you are assuming that all the fuses in the fuse panel are supplied by a single high current bus in the same way that a house fuse box is. However that is often not the case in an automotive fuse panel, the fuses are often (I think normally) supplied by individual wires which are only rated to match the fuse.
 

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#66
I think you are assuming that all the fuses in the fuse panel are supplied by a single high current bus in the same way that a house fuse box is. However that is often not the case in an automotive fuse panel, the fuses are often (I think normally) supplied by individual wires which are only rated to match the fuse.
The hot side of the fuse box is divided into segments. (all the fuse boxes, in and outside the car) Each segment is fed by relays/ circuit breakers that close (turn on) as required, thus there is a bank that turns on with the key, on with the key in ACC, a bank that turns on with the key in the starter position, a bank that is turned on all the time...........
 

Nigel

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#67
The hot side of the fuse box is divided into segments. (all the fuse boxes, in and outside the car) Each segment is fed by relays/ circuit breakers that close (turn on) as required, thus there is a bank that turns on with the key, on with the key in ACC, a bank that turns on with the key in the starter position, a bank that is turned on all the time...........
If that is the case then you really don't know what the system is capable of supplying to each fuse, a 10A fuse may be supplied by a 10A relay and when you pull 15A through it the relay will burn out. In my car some of those relays, such as the door lock motors and window motors are soldered on the same circuit board as the security and alarm system and when they burn out (which does happen) you are in a bit of expensive trouble!
 

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#68
I suspect the engineers that design the assembly take into account the total load on each segment. And.. yes you could overload an individual segment... with expensive consequences. There needs to be a tad of intelligence in play when adding a circuit, expecting to draw 100 amps from the fuse box inside the car just because you can add a 100 amp fuse is likely to end badly..:oops:
 

Nigel

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#69
I suspect the engineers that design the assembly take into account the total load on each segment. And.. yes you could overload an individual segment... with expensive consequences. There needs to be a tad of intelligence in play when adding a circuit, expecting to draw 100 amps from the fuse box inside the car just because you can add a 100 amp fuse is likely to end badly..:oops:
Yes, they will certainly make sure that the total load that can get through the fuses is no more than the total capacity of the segment. And if you make sure that you retain the original fuse ratings and make sure that any taps are taken from after the original fuses by putting the fuse taps the correct way around then you know for sure that everything is safe.
 

Hillbilly

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#70
View attachment 20358 View attachment 20359

I must be thick, but I can't figure this out. I have attached a couple diagrams for you to look at to see why I think it makes no difference, well except in one the PMP is protected by both the 30 amp and the 5 amp, whereas in the other way only the 5 amp. But if I'm wrong I need to check my installation because I never considered there was a right or wrong way to put in the fuse tap.
To answer this very old question, the correct way is the second picture. When you insert a fuse in a circuit you apply voltage on one side and take it out the other or the fuse wont work, In the first pic the V has to go first through the 30 amp fuse and then out the 5 amp one to get to the wire. So why do you need 2 fuses on what has been made effectively one circuit by inserting it incorrectly.
In the second pic the V is coming in on the correct pin and being divided between the two fuses and out the other pin and the wire. If you pull either fuse V to that circuit will cease

Anyway if you use the original plug from the camera it has a 2 amp fuse in it anyway.

Always remember a fuse is put there to protect the vehicle from the appliance. NOT the appliance from the vehicle
 

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#73
what that is saying effectively is if you install a fuse tap the wrong way around the circuit is not fused at all and needs an inline fuse added, there may be situations due to clearance where it is not possible to install the tap in the correct orientation
 

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#74
I have never seen a fuse tap that does not incorporate a fuse in its design, is there such a thing?
 

jokiin

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#75
I have never seen a fuse tap that does not incorporate a fuse in its design, is there such a thing?
even though they have a fuse if installed the wrong way around they are effectively unfused on the auxiliary circuit, the original circuit will still be protected either way
 

CDNinHH

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#76
oh oh.....I'm not going to get into this again.
 

Rajagra

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#77
I have never seen a fuse tap that does not incorporate a fuse in its design, is there such a thing?
Their fuse taps are clips that attach to one side of a fuse. They are not like add-a-fuses. Potentially much more risky.

Sent from my tap-to-talk using Tapatalk
 

CDNinHH

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#78
Their fuse taps are clips that attach to one side of a fuse. They are not like add-a-fuses. Potentially much more risky.
Ahh, ok....interesting.
 

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#79
They are no better than stuffing a wire down the side of a fuse A recipe for disaster if ever I saw one.

The picture I posted on page 3 is the correct way to do it
 

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#80
The picture I posted on page 3 is the correct way to do it
So....not wanting to start this all over again, because you have your opinion on it, but without using a multi-meter how do you know which side of a tap is the direct side ( as shown in blue on the left side in your diagram) is there any markings on the those taps that show that is the linked side as opposed to the right side being the linked side?
 

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