Battery draining overnight
Understanding this^^^ will be key to setting up trouble free circuitry.
Depending on how/when the fans will be running, may want to connect their power wire to a terminal stud from the alternator output.*
Whether to use a stock or aftermarket ammeter in the battery feed/charge circuit depends on how frequently and how long electrical accessories will be run on battery. If the battery is going to be deep cycled, then neither the factory circuit or a regular automotive starting battery is going to be happy for long. I'm describing describing long periods of discharging (running fans or an amp with engine off) and then resulting recharge cycles where the battery is sucking over 20 amps for a minute or more.
*Gray arrow pointing to a terminal stud used as a power distribution point.
Notice the alternator, ammeter and 6 gage wires are by a 10 gage fusible link at the first terminal stud.
Then the 10 gage and smaller wires and connections are protected by a 16 gage link (same as in a standard option wiring).
If other circuits with smaller wires were added to that same stud, then they too need protection.
This is the other important point in your circuit design.
Protect the wiring with fuses, breakers, or fusible link based on the smallest wire or weakest link in the circuit.
Use a link where short term, higher current loads are to be expected, but protection against a battery short to ground is needed.
Only when the engine is off.
Understanding this^^^ will be key to setting up trouble free circuitry.
Depending on how/when the fans will be running, may want to connect their power wire to a terminal stud from the alternator output.*
Whether to use a stock or aftermarket ammeter in the battery feed/charge circuit depends on how frequently and how long electrical accessories will be run on battery. If the battery is going to be deep cycled, then neither the factory circuit or a regular automotive starting battery is going to be happy for long. I'm describing describing long periods of discharging (running fans or an amp with engine off) and then resulting recharge cycles where the battery is sucking over 20 amps for a minute or more.
*Gray arrow pointing to a terminal stud used as a power distribution point.
Notice the alternator, ammeter and 6 gage wires are by a 10 gage fusible link at the first terminal stud.
Then the 10 gage and smaller wires and connections are protected by a 16 gage link (same as in a standard option wiring).
If other circuits with smaller wires were added to that same stud, then they too need protection.
This is the other important point in your circuit design.
Protect the wiring with fuses, breakers, or fusible link based on the smallest wire or weakest link in the circuit.
Use a link where short term, higher current loads are to be expected, but protection against a battery short to ground is needed.
