Alaskan Camper Wiring Check

[Cgswimmer24]

I just got back to Alaska after picking up a new Alaskan Camper from Washington and had issues with my battery monitor on the trip home.

I have two 162AH Expion 360 lithium batteries with two solar panels, DC to DC charger and a Redarc charger. My Expion 360 battery monitor would decrease from 100% to zero without ever coming back up. The solar controller would show 100% and I know the unit has power but the battery monitor never increases. For example, we'll start the day off with the monitor reading 89%. After driving 15 hours with the DC to DC connected in full sunlight we park for the night and it's reading 72%. It will eventually decrease and stay at 0%. I reset it back to 100% a few times and it still only shows draw, no charge.

The only change I've noticed is when I got home and plugged it into the house on shore power. It brought it up from 0% to 80% overnight.

I talked to the E360 tech rep and their first take was that the system isn’t wired correctly but they’re sending out a new monitor to test first. Alaskan hasn’t been any help at all, telling me it’s wired right. But the E360 tech rep did tell me they’ve had to reach out to Alaskan in the past about other wiring issues Alaskan has not done properly.I’ve attached a few photos if anyone could provide some input. Much appreciated

Steve

 

[ripperj]

I see a negative that connects straight to the battery. The shunt should be the first thing that connects to the battery and everything else should connect to the other end of the shunt .
If the white wire connected directly to the battery is the charger or the solar controller , the shunt can’t measure the current.
Battery monitors typically have to be setup with the proper battery capacity and then initialized. You can usually do this manually. Once the battery is fully charged you go into the setup menu and tell the monitor that the charge is 100%. Many monitors have an automatic way of doing this also.

I’d find out what that white wire is and see if makes sense that it bypasses the shunt.
If you are not familiar with, the shunt is a precision resistor and the monitor measures the voltage across it and converts to amps or watts (current and power)


Sent from my iPhone using Tapatalk Pro

 

[jonyjoe101]

The expion 360 monitor is the same I use (but mine is named the tk15 coulombcounter). More than likely you have voltage drop from the controller to your battery.
All solar controllers read high, I never had one that read what the actual battery voltage was. That means your battery isnt getting fully charged. I can tell because the controller is reading full but your expion is only reading 13.65 volts. If the battery was really full it would be reading at least 14.4 volts (maybe 14.6 volts if you want max charge on the lifepo4).
The expion 360 monitor wont reset to full until it actually sees 14.4 volts (or what ever the max voltage you program into it). If the battery is never reaching full charge 14.4 volts, eventually the expion 360 wont know what the actual SOC of the battery is and you get what is on the screen.
The only way to fix the problem is to calibrate the solar controller so it reads the same voltage as the battery terminals. Example if the solar control reads 14.4 volts the battery terminals (expion 360) should also read 14.4 volts. Some controllers can be calibrated. If you have a controller that cannot be calibrated, you have to set the controller bulk setting to "user input" instead of lifepo4 or lead acid. Then if you have .5 voltage drop you have to raise the bulk voltage from 14.4 volts to 14.9 volts to compensate. The voltage on the controller needs to match what the expion 360 reads.
On my ecoworthy 20 amp mppt, I had a 1 volt voltage drop, I had to raise the bulk voltage to 15.5 volts to fully charge my lifepo4 to 14.6 volts. The only mppt controller that I tested that has voltage calibration is the makeskyblue 60 amp. I bought it just for that feature and it works excellent.

Here is a picture that shows voltage drop on my TK15. A properly calibrated solar controller will ensure you get maximum amps into your battery.

tk15 directions to set the full voltage. This will apply to your monitor, they are same.

 

[jonyjoe101]

As ripperj mentioned on the monitor sensor, the 2 white wires can be removed. On the P- there should only be 1 wire the negative for power out and also power in to charge the battery.
But also check for voltage drop once you fix that.

 

[Cgswimmer24]

I see a negative that connects straight to the battery. The shunt should be the first thing that connects to the battery and everything else should connect to the other end of the shunt .
If the white wire connected directly to the battery is the charger or the solar controller , the shunt can’t measure the current.
Battery monitors typically have to be setup with the proper battery capacity and then initialized. You can usually do this manually. Once the battery is fully charged you go into the setup menu and tell the monitor that the charge is 100%. Many monitors have an automatic way of doing this also.

I’d find out what that white wire is and see if makes sense that it bypasses the shunt.
If you are not familiar with, the shunt is a precision resistor and the monitor measures the voltage across it and converts to amps or watts (current and power)


Sent from my iPhone using Tapatalk Pro

It looks like that grey/white wire connected to the negative terminal of the battery goes to the negative terminal of the other battery.

I have manually adjusted the monitor back to 100% a few times with the same issue. It just slowly draws down each day until it eventually reads 0% and stays there.

 

[Cgswimmer24]

The expion 360 monitor is the same I use (but mine is named the tk15 coulombcounter). More than likely you have voltage drop from the controller to your battery.
All solar controllers read high, I never had one that read what the actual battery voltage was. That means your battery isnt getting fully charged. I can tell because the controller is reading full but your expion is only reading 13.65 volts. If the battery was really full it would be reading at least 14.4 volts (maybe 14.6 volts if you want max charge on the lifepo4).
The expion 360 monitor wont reset to full until it actually sees 14.4 volts (or what ever the max voltage you program into it). If the battery is never reaching full charge 14.4 volts, eventually the expion 360 wont know what the actual SOC of the battery is and you get what is on the screen.
The only way to fix the problem is to calibrate the solar controller so it reads the same voltage as the battery terminals. Example if the solar control reads 14.4 volts the battery terminals (expion 360) should also read 14.4 volts. Some controllers can be calibrated. If you have a controller that cannot be calibrated, you have to set the controller bulk setting to "user input" instead of lifepo4 or lead acid. Then if you have .5 voltage drop you have to raise the bulk voltage from 14.4 volts to 14.9 volts to compensate. The voltage on the controller needs to match what the expion 360 reads.
On my ecoworthy 20 amp mppt, I had a 1 volt voltage drop, I had to raise the bulk voltage to 15.5 volts to fully charge my lifepo4 to 14.6 volts. The only mppt controller that I tested that has voltage calibration is the makeskyblue 60 amp. I bought it just for that feature and it works excellent.

Here is a picture that shows voltage drop on my TK15. A properly calibrated solar controller will ensure you get maximum amps into your battery.
View attachment 847698
tk15 directions to set the full voltage. This will apply to your monitor, they are same.
View attachment 847699

I’m pretty ignorant to all things electrical so to be honest, I only understand part of what you’re saying. Here’s a photo of what everything is reading now, including what the Expion360 app is saying based on being connected via Bluetooth to the batteries. Everything is saying full at 13.7V, so I understand something is wrong there because full should be 14.4v on these batteries. So, in your opinion, this is something that can be corrected by recalibration? Or the wiring was done incorrectly and I need to take it into a shop to have it done correctly?

 

[Cgswimmer24]

As ripperj mentioned on the monitor sensor, the 2 white wires can be removed. On the P- there should only be 1 wire the negative for power out and also power in to charge the battery.
But also check for voltage drop once you fix that.
View attachment 847703

I’ll give it a try moving these around. Thanks!

 

[ripperj]

I missed the fact that you had two batteries. It makes sense that the wire from the second battery connects to the battery terminal on the first. I wouldn’t change anything unless you are sure what the result will be.


Sent from my iPhone using Tapatalk Pro

 

[jonyjoe101]

the white wire going to the second battery should be on the battery terminal directly. Right now as the picture shows its connected to the P- of the sensor. Remove the small white wire completely, and disconnect the second battery wire from the P- and connect it where the small wire was on the battery - terminal. I think that should fix your problems.

 

[Cgswimmer24]

the white wire going to the second battery should be on the battery terminal directly. Right now as the picture shows its connected to the P- of the sensor. Remove the small white wire completely, and disconnect the second battery wire from the P- and connect it where the small wire was on the battery - terminal. I think that should fix your problems.

It’s hard to tell from the first photo I posted, but the white wire is going directly to the terminal. Here’s a better photo

 

[jonyjoe101]

On the sensor P- there is a black wire and also a white wire, where do those wire go? on mine there is only one wire which is input and output.
If the black and white wire connect to a common busbar then it should be ok. Thats the only way the sensor will be able to record accurately charging and discharging.

 

[Cgswimmer24]

On the sensor P- there is a black wire and also a white wire, where do those wire go? on mine there is only one wire which is input and output.
If the black and white wire connect to a common busbar then it should be ok. Thats the only way the sensor will be able to record accurately charging and discharging.

The white one goes to a bus bar, and it’s hard to track where the black one goes. I can track it up to where my solar and IOTA charger controller is but lose it in that mess of wires.

 

[jonyjoe101]

Everything seems to be connected correctly. It probably just needs a good charge to 14.4 or 14.6 volts to get the battery monitor to reset to 100 percent.
On my 220ah lifepo4 when I discharged it to 0 percent, it took me almost 2 weeks to fully charge back to 100 percent (14.6 volts on my battery) with a 240 watt solar panel.
The voltage on the battery monitor since it reads directly from the battery terminals will be more accurate than the mppt solar controller, if you don't see it reaching 14.4 volts during charging, than you definitely have a voltage drop problem.
If your not getting max amps from your solar panels, its definitely a voltage drop problem. From a 240 watt panel I was averaging about 12 amps, from my 365 watt panel I can get up to about 18 amps.
If your mppt controller is reading full too early (or going into float) thats also another sign that you have a voltage drop problem.

 

[Cgswimmer24]

Everything seems to be connected correctly. It probably just needs a good charge to 14.4 or 14.6 volts to get the battery monitor to reset to 100 percent.
On my 220ah lifepo4 when I discharged it to 0 percent, it took me almost 2 weeks to fully charge back to 100 percent (14.6 volts on my battery) with a 240 watt solar panel.
The voltage on the battery monitor since it reads directly from the battery terminals will be more accurate than the mppt solar controller, if you don't see it reaching 14.4 volts during charging, than you definitely have a voltage drop problem.
If your not getting max amps from your solar panels, its definitely a voltage drop problem. From a 240 watt panel I was averaging about 12 amps, from my 365 watt panel I can get up to about 18 amps.
If your mppt controller is reading full too early (or going into float) thats also another sign that you have a voltage drop problem.

What would be some of the more common issues that cause voltage drop?

 

[jonyjoe101]

What causes voltage drop with solar is that controllers arent properly calibrated at the factory, they all read high. Every controller I used (pwm or mppt) was reading high, anywhere from .5 to 1 volt high. If the solar controller was reading 14.4 volts the actual voltage on the battery terminals would be 13.4 volts. In this situation the controller thinks the battery is full and reduces amps to 1 amp or less.
I have tried using 10 guage wire (largest gauge that fits on the controller) from controller to battery to reduce the voltage drop, but that doesnt help much.
Very few controllers can be calibrated, the only thing that works is raising the bulk voltage on the controller to compensate for the voltage drop.
I discovered the voltage drop problem when I switched from lead acid to lithium batteries. With lead acid its guess work if the battery is full. With lithium the battery has to reach a certain voltage to be full.
The controllers I was using showed that my lithium battery was full and switched to float, but my lithium battery voltage was nowhere near full.