Volt Drops?

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One for the electrical gurus I think.
I have twin agm hab batteries connected to Victron regulator.
Having checked the whole system I have the following.
From regulator output to batteries I have a volt drop of about 1.3v.
A bit for each section of wiring plus about .7v across the Sargent control box.
This results in a slightly low absorption voltage at the batteries.
Rewiring would improve it, but not inormously.
My question is:

As I can adjust the absorption and float voltages, would it be OK to 'adjust ' the Victron settings that would achieve the desired voltages at the batteries? Thereby negating the volt drops.

Geoff
 
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What exactly do you mean by a Victron regulator? Does it regulate the charge from the solar, alternator or mains charger?

A mains charger probably has 'voltage sense' wires that can be fitted, which automatically tell the charger to increase the voltage to maintain the correct battery voltage.

A Victron solar controller (if it has Bluetooth) can get battery voltage information from a 'BatterySense' module that sticks on the battery. It transmits by Bluetooth, and allows the solar controller to adjust the output voltage to the correct value.
 
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Thanks Autorouter, that's the tool.
I had not come across it, but having now looked at spec, it will do what I want.
I guess there is not a simpler way of connecting a battery voltage sensing wire to the controller?
By the way it is a Bluesmart 100-15

Geoff
 
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I don't think it has any direct battery measurement sensing wires, like the mains chargers have. However if you get a BatterySense module and stick it on the side of the battery, it will also sense the battery temperature and adjust the voltage for that as well.

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Thanks again. I see there are two versions: short and long range = 3m or 10m range. I have gone for the 10m range to future proof the system.
My main concern is undercharging the AGMs for long periods, apparently not good for them.

Geoff
 
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Thanks again. I see there are two versions: short and long range = 3m or 10m range. I have gone for the 10m range to future proof the system.
My main concern is undercharging the AGMs for long periods, apparently not good for them.

Geoff
That’s why I try to tell ppl to size the wire from controller to batts properly to reduce the voltage drop to almost 0, or reasonably practical. You can have a bit of drop from panels to controller, but not from controller to batt. Not allowed, as it will mess the settings. I have a 100/50 controller with 16mm2 cable run 0,6m max to batt. I still get some voltage drop, and use a batt sense networked with the charger to compensate for the drop. I could run a 25mm but space is tight.
 
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That’s why I try to tell ppl to size the wire from controller to batts properly to reduce the voltage drop to almost 0, or reasonably practical. You can have a bit of drop from panels to controller, but not from controller to batt. Not allowed, as it will mess the settings. I have a 100/50 controller with 16mm2 cable run 0,6m max to batt. I still get some voltage drop, and use a batt sense networked with the charger to compensate for the drop. I could run a 25mm but space is tight.
Hi
My biggest volt drop is across the Sargent control box, with no obvious cause, more an accumulation of various components. I could bypass the Sargent but it does have some useful features.
Looking at the battery sense I think it will correct this charge at the batteries.

Geoff
 
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