# Alumapro the C.A.P. 15 wiring ?



## poochieone (Aug 25, 2005)

Hi,
I have a CAP 15 which i'm trying to wire into my system. question is, i'm not sure if i need to run the main power wire for the system through the large relay for the CAP (and then feed the CAP's positive outputs to the power distribution block) or if i can run an additional length of wire (parallel) from the battery (battery is in the trunk so is a short run) through the Large relay to the Cap itself and then feed the CAP's positive and negative outputs into my power and ground distribution blocks. 
I've asked the same question to Alumapro but they have provided no response.
thanks for your time,
Marco


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## Oliver (Jun 25, 2007)

water analogy

storage tank 

how it works, resist voltage change or when pressure drops it adds some water to bring pressure back up.

Short answer, YES


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## St. Dark (Mar 19, 2008)

I think what he meant (since you asked an "either/or" question) was either way will work.
If I understood you: you want to know if you can put the CAP (through it's relay) in line on the existing power wire or if you need to run a whole new, additional power wire (thjough the relay) and then pipe the CAP's outputs into spare taps on your distros? That being the case, then "YES" the two are basically the same electrically.
If your current power cable is sufficiently large for the job at hand, then you would not NEED to run an additional one just to put the CAP in. But, if you feel the urge to buy more copper, and have paid proper attention to your underhood grounds etc. and have the time to kill, go ahead. No one ever said any power cable was too BIG other than maybe the guy who job it was to hide it.


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## atsaubrey (Jan 10, 2007)

good luck on the Alumapro stuff, great stuff no doubt but my experience with your EXACT situation and help from Alumapro sucked. Good luck


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## kt4000m (May 26, 2008)

ive run my cap 15 without the relay, for about 2 years. 
ive never had an issue. the relay is for discharging and 
recharging upon system turn off,on. its also only a 100amp
relay, so any draw over 100 amps you must add relays.
thats what alumapro told me. as i have the potential 
to draw 300 amps, i decided to leave out the relay.
its supposed to be bad for the cap, not being discharged 
and recharged every time. but i still havent had an issue
after 2 years. good luck.

kt


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## poochieone (Aug 25, 2005)

thanks Gents.
my system has the capacity to draw approx 390 amps at full tilt but it will never even come close to that. i would estimate no more than 130 amps the way i listen to it. 
i'm already running 0 gauge as the main wiring and its less than 5 ft long. 
one of my concerns (thus wanting to run the CAP as stated above) was the capacity of the system to pull well beyond 100 amps through that relay. since its not inline on the main power wire, i figure once the cap reaches its limits, the remainder of the power can be sourced directly from the battery through the 0 gauge wiring. am i on the right track?


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## kt4000m (May 26, 2008)

the relay does go to the main power. you hook it up between the battery and the cap. thats the only way it can be used. you better check the relay wiring instructions. it shows the relay just before the cap breaking the pos.
main in. the alumapro website has one [relay wiring diag] you can download.
good luck.

kt


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## poochieone (Aug 25, 2005)

Kt,
i do have the diagram and understand that wiring, but i'm trying to do something a bit different... i don't want to run my full system's power through that 100 amp relay...


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## poochieone (Aug 25, 2005)

Hello again,
i bring this back up because i finally dressed all the wiring and installed the Cap with its own power wire coming directly off the battery running parallel to the main system power wire. the car now has some sort of power drain that cleaned the battery (good thing its a deep cycle). i've double checked the rest of the wiring and it all looks good, matching the set up instructions provided by Alumapro. 
I now need to know how to fix this... do i need to only have one power wire running through the relay and feeding the system?
again,
any help is appreciated.
thanks


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## poochieone (Aug 25, 2005)

4th page bump


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## poochieone (Aug 25, 2005)

still looking for some help...


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## exmaxima1 (May 31, 2007)

poochieone said:


> still looking for some help...


The CAP15 is made of a series of cells and employs a resistor ladder network to equalize the load among the cells. As a result, The CAP15 draws a quiescent current of about 50 mA when in use. While a rather small drain, it can deplete a battery in a few days if the engine is not running while in use. Typical car applications are with the engine running, and the large relay is intended to isolate The CAP from the system when the engine is off.

In addition, The CAP15 has a 20 ohm drain resistor internally connected between the center and positive terminals. When the system is off, the small relay provides a ground path to the center terminal to discharge The CAP.

It sounds like you may have wired your system in a fashion that either: 1.) leaves The CAP connected to power at all times, and a drain of about 50mA, or 2.) provides a drain path for the center terminal which will drain a battery in a short time----The CAP will also get very hot!

My suggestion is to delete the center wire entirely--the drain function is not mandatory and rarely desirable (it was originally intended as a safety feature). With it deleted, The CAP15 will still discharge, but it will take hours rather than minutes. If The CAP voltage IS NOT dropping when the system is turned off, there is a wiring error somewhere (likely a parallel feed) and that is is the cause of the battery discharge.

Good Luck,

Matthew


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