location of neg lead fm battery in IOTA distribution panel?

[Rhett25]

Looking for neg lead from battery at the distribution panel. Looking to install a shunt and meter. I see the pos connection from the battery and the pos lead to the converter. The remaining leads appear supplies from a fuse to dc service.

Panel appears to be an IOTA 3045.

Thanks

[CA_Traveler]

This is my battery monitor shunt and disconnect switch. While the house batteries are AGM (with no corroding fumes) there are nearby flooded starting batteries. I spray the shunt and the connections with a battery protector.

[CA_Traveler]

OP, The negative distribution uses the frame with negative wires connected at various points in the RV. The panel fuses and distributes the positive connection only. There may be a limited negative ground for panel lights, etc. Hence there is no place to install the shunt on the negative lead and near the battery is the best location.

[CA_Traveler]

Good post from DrewE, one size doesn't fit all. Also what is a battery monitor and at what accuracy? A volt meter, a amp meter, Ah or Wh, accumulated power, some time related information, etc.

I would be cautious about installing a shunt near the converter. There may be loads from there to the battery, if not amps will be accurate but volts will be lower due to wiring loss. My full function battery monitor has wires directly from the shunt and + - battery and hence it knows and tracks battery power. From my experience the hall-effect current sensors are not as accurate as the shunt type.

There are lots of options.

I have a $20 "battery monitor" with shunt that displays V, A, W and Wh that I use to monitor the supply for a pricey radio. It only measures current in one direction. With a manual reset it displays Wh and hence the discharge and SOC starting with a fully charged battery.

[DrewE]

MrWizard wrote:
The SHUNT can be in the positive wire
The shunt doesn't care
It's just usually easier to install it on the negative lead, because there is less wiring to contend with ( normally done at the battery where there are several wires connected to the positive post ) ( you don't have that concern inside the iota with only one positive wire going to the battery )
Just reverse the polarity of the signal wires from the way shown for the normal installation in the negative lead
As long as it shows plus amp flow when charging
And minus amp flow when discharging
You are good

For analog meters, this is true. It's also true for digital meters where the sensing is isolated from the meter's power supply (which includes all that use hall-effect current sensors, and some others). For many digital panel meters, however, one of the current sense lines is internally connected to the negative supply for the meter, so if the meter is powered by the 12V system for the RV and no external isolation is provided for the meter's power supply, the shut must be on the negative lead. Sometimes this information is rather buried in their description or documentation.

[MrWizard]

The SHUNT can be in the positive wire
The shunt doesn't care
It's just usually easier to install it on the negative lead, because there is less wiring to contend with ( normally done at the battery where there are several wires connected to the positive post ) ( you don't have that concern inside the iota with only one positive wire going to the battery )
Just reverse the polarity of the signal wires from the way shown for the normal installation in the negative lead
As long as it shows plus amp flow when charging
And minus amp flow when discharging
You are good

[Fisherman]

What Rhett25 said, they are too cheap to install an 8 or 10 ga. ground wire (negative) from the battery location to the distribution panel. Found the same on mine. Battery is grounded at the front of the trailer and they run another wire from the frame up through the floor to the distribution panel. Save 15 feet of wire, yet need to install 2 ground points on the frame that will corrode quickly.

[CA_Traveler]

Battery negative leads usually go to frame ground which is where the shunt needs to be installed.