What is meant by "All Negative Load Wires" ? in wiring a Aili battery monitor shunt ?

[Eucle]

I have installed an AilI battery monitor in my truck camper solar system. I am getting seemingly accurate Voltage readings but the current seems to be reading high as compared to the readings on my hand held clamp ammeter. ( used on the white or black wire only in the output wire between my inverter and the ATS ) I have viewed countless You Tube videos and I think I have it wired correctly, but I keep seeing the phrase " all negative load wires attached to P side " What are the negative load wires, where do they come from? From what devices or appliances do they have to come from. My inverter is wired directly to a stand alone ATS, which is wired into the back of the electrical panel There the green wire goes to a ground buss, the white goes to the neutral buss, and the black wire goes to the circuit breakers. Do I have to connect another wire from the electrical panel to the monitor shunt? They are at opposite ends of my truck camper. I am perplexed because I was able to understand how to put together the entire solar system which works great, but can't figure out what the " negative load wires " are. Any enlightment will be appreciated

 

[mikefitz]

Your batteries will have a connecting cable to the common negative of your DC system from the battery negative terminal. Disconnect this cable and connect to the shunt P-, connect with an additional cable the battery negative terminal to B-.
Any other cables that may have been connected to the battery negative are removed and reconnected to the P-.
To avoid multiple connections to the P- a buss bar could be used.

Nothing else connects to the battery negative, except the negative of parallel batteries.

See, https://www.compactrv.net/free-camp.../recharging-batteries/battery-charge-monitor/





Mike

 

[Eucle]

Your batteries will have a connecting cable to the connon negative of your DC systen from the battery negative terminal. Disconnect this cable and connect to the shunt P-, connect with an additional cable the battery negative terminal to B-. Any other cables that may have been connected to the batterynegative are removed and reconnected to the P-. To avoid multiple connections to the P- a buss bar could be used.

Your batteries will have a connecting cable to the common negative of your DC system from the battery negative terminal. Disconnect this cable and connect to the shunt P-, connect with an additional cable the battery negative terminal to B-. Any other cables that may have been connected to the battery negative are removed and reconnected to the P-. To avoid multiple connections to the P- a buss bar could be used. View attachment 113362 View attachment 113363 Mike

Your batteries will have a connecting cable to the common negative of your DC system from the battery negative terminal. Disconnect this cable and connect to the shunt P-, connect with an additional cable the battery negative terminal to B-. Any other cables that may have been connected to the battery negative are removed and reconnected to the P-. To avoid multiple connections to the P- a buss bar could be used. View attachment 113362 View attachment 113363 Mike

Your batteries will have a connecting cable to the common negative of your DC system from the battery negative terminal. Disconnect this cable and connect to the shunt P-, connect with an additional cable the battery negative terminal to B-. Any other cables that may have been connected to the battery negative are removed and reconnected to the P-. To avoid multiple connections to the P- a buss bar could be used. View attachment 113362 View attachment 113363 Mike

 

[Eucle]

Sorry if you see a bunch of repeats of your message, I am new to this site and still figuring out how it functions. I looked at the diagrams you provided and it raised the ?, the fridge ground was switched from the negative side of the battery, to the P side of the shunt. I don't understand how that is done. In my system, I have the original battery then 4 more Agm batteries in parallel. On the last battery, I have a 2/0 cable running to the B- side of the shunt. There is nothing else connected to the negative posts of any of the last 4 batteries, ( I did add a buss bar between the 3rd and 4th battery and added an additional chassis ground to that buss the 4th battery negative is connected to that buss bar ) I would imagine the original battery ( 1st in line ) is still grounded to chassis. At the shunt, I have the cable from 5 th battery negative post connected directly to the B- side of shunt, the other side P is connected by 2/0 cable to the negative of my inverter. So, do I need to disconnect any wires on the negative post of battery one and connect them to the P side of the shunt? Would this be like re-wiring the fridge in the first diagram so it is connected to the P side of the shunt. Would this be the " negative load wires " that is mentioned, and what additional loads might need to be switched? Any thing run by AC? Sorry for all the ?s, trying to reconcile the wiring in the diagram with the way the wiring is in my camper. Thank you for your response.

 

[Rednecktek]

Here's the simple answer that should fix your issue:

Batteries Neg -> Shunt B- -> Shunt P- -> Everything else.

Anything that is connected to the battery bank negative that DOESN'T go through the P- bolt on the shunt isn't getting detected by the shunt and will throw all your numbers out of whack.

Also, once you get everything going through the shunt you'll probably need to reset your shunt display to get rid of it's programmed errors from not reading things correctly. Top up the batteries and reset to 100% and everything should be zeroed out good after that.

 

[Bud Martin]

I have installed an AilI battery monitor in my truck camper solar system. I am getting seemingly accurate Voltage readings but the current seems to be reading high as compared to the readings on my hand held clamp ammeter. ( used on the white or black wire only in the output wire between my inverter and the ATS ) I have viewed countless You Tube videos and I think I have it wired correctly, but I keep seeing the phrase " all negative load wires attached to P side " What are the negative load wires, where do they come from? From what devices or appliances do they have to come from. My inverter is wired directly to a stand alone ATS, which is wired into the back of the electrical panel There the green wire goes to a ground buss, the white goes to the neutral buss, and the black wire goes to the circuit breakers. Do I have to connect another wire from the electrical panel to the monitor shunt? They are at opposite ends of my truck camper. I am perplexed because I was able to understand how to put together the entire solar system which works great, but can't figure out what the " negative load wires " are. Any enlightment will be appreciated

I think you are confused about the DC and AC current readings.
The Ali battery monitor is for reading the batteries DC current draw.
The Black (LINE/HOT) and White (Neutral) are AC, so when you try to read the AC current on the Black or on the neutral wire it will not be the same as DC current reading on the battery wire. The inverter converts DC input to AC output, for example (dis regard the conversion loss for now) if you are converting 12VDC to 120VAC for 1000W, the AC current will be 1000W/120VAC = 8.33A, that means the DC current draw from battery will be 1000W/12VDC = 83.33A.
Also, the Inverter is the DC Load as far as what the battery is seeing, the AC loads are what ever AC devices plugged into the AC outlet or AC output terminals of the inverter, so to monitor the AC current you will need AC current meter.

 

[Eucle]

I read that same thing this afternoon and it makes good sense to me. The position of the shunt is in the DC circuit, so it makes sense it would measure DC current. And the high current readings compared to the AC current readings I got with a hand held clamp ammeter are what were bothering me. I measured separately and cataloged the AC current of each appliance I use, refrig, microwave, electric heater etc. using an AC clamp ammeter on a segment of the output line from the inverter, while they ran off the inverter. I also divided the 3000 Watt inverter output by 120 volts and got 25 amps, 50 amps when the inverter covers the surges ( 6000 Watts ). I think what I am going to do is just be aware of what appliances I am using at the same time, keep the total amps well under the 25, and if I have any concerns, I can re-check with the AC clamp ammeter. I keep it in the truck camper. I think that is a realistic approach. I noted the air conditioner spiked 39-41 AC amps for a short time when the compressor kicked in so I will probably only use it when on shore power or on generator ( 4000 Watt ) I will continue to use the battery monitor to measure the battery voltage, it matches the voltage on the charge controller within .1 Volt. And I keep a chart taped up in one of the cabinets that show the % of charge for each decrease in voltage, 12.9, 12.8, 12.7 etc. Thank you for helping me see this more clearly,

 

[mikefitz]

The battery monitor is for DC volts, amps and power.
The term 'all negative connec tions' refers to DC connections, not AC power cables, hot or neutral.
If you have any chassis grounds to the battery remove them.
There should only be a chassis ground from the shunt P-, so the shunt measures all current in the negative path.
The appliances in the diagram are DC appliances.

Having the battery monitor accurately connected would give far more useful information than volts and help battery management.

 

[Tomthumb62]

This monitor looks like a knock off of the renogy one. Are they similar or any comparison reviews?