true smart battery isolator installation

True smart battery isolator installation install#
True smart battery isolator installation full#

The only difference from that and the setup you've pictured is where the fuse is. I recently did my dual-battery setup and I ran my cables from the starting battery, not the alternator. On my vehicle, all the loads (including the normal vehicle loads shown on the Hellroaring diagram) are connected on the battery terminal, not the alternator, so all alternator current normally flows through that cable anyway, so I felt safe doing it that way. If the vehicle's alternator cable was close to it's max safe capacity, adding the aux-charging load to the alternator side means current doesn't flow through the alternator-to-battery cable during charging, whereas it DOES flow through that cable if connected to the starting battery terminal. One other difference to wiring it my way versus the Hellroaring diagram is whether the current flows through the alternator cable or not. As dwh points out, connecting to the alternator or to the positive terminal of the battery is the same voltage potential, and really only a difference of a foot or two of cable probably. Other than that, there really isn't much difference between my diagram and Hellroarings.

True smart battery isolator installation install#

I weighed this risk against the ease of install and decided I'd rather run all the wires from the control unit to the same spot in the engine bay.

Now, it's a big cable, so the voltage drop 'should' be negligible, but the reality is that every foot of cable, every connector, and every breaker in the line adds a little impedance and the chance of something going wrong. So taking that and looking at my diagram, you can see that the biggest 'flaw' is that I'm sampling the Aux battery voltage where it connects to the solenoid, rather than close to the battery.

True smart battery isolator installation full#

That's the same reasoning why they urge a full ground cable for the battery and not using a chassis ground - the two batteries could end up at slightly different potentials if done otherwise. In other words, the system is based on having an accurate measurement of the battery voltages, and if you wire the connections such that you introduce any small differences in the sampled voltage, you might lose efficiency or even create charging problems. Unless, anyone can point out a shortcoming with this approach, I think I'm essentially copying your setup.Ĭlick to expand.I'm not sure how the Hell Roaring system makes it's decisions, but I will say this, both the National Luna and IBS make it a point to caution a few things about installation: namely that the 'measurement' connections that lets the unit(s) sample the battery voltages should be as close to the batteries as possible to avoid any sort of differences in voltage potential. I have a lead that is linked to the ignition that I capped off so I could easily extend that to the isolator as well. Grounding to chassis works but wanted the option for a better ground. The fuse box I'm looking at is a Blue Sea 5026 that has it's own neg. > Breaker -(long cable run)-> Isolator -> Breaker -> Aux. So my proposed setup is:Īlternator -> Main Batt. I have space on the passenger side wall to install another breaker, an isolator, and a 12 circuit fuse box. post would be easy for me, I would just need to add an extension. This is my current setup:Īlternator -> Main Batt. Herbie - Are there any pros/cons of doing it the way you did versus what Hell Roaring shows?