When using the VE.Smart voltage sense and a Phoenix Smart IP43 Charger, the output voltage will reliably rise to 2V above the set point when the following is true:
VE.Smart voltage sense is enabled and connected
The IP43 is in Power Supply mode
The set IP43 output voltage is EQUAL or GREATER than the sensed battery voltage
Under these circumstances the IP43 output voltage increases slowly until stopping at 2V over the set point (15.2V in this case). However, the battery sensed voltage shouldn’t matter in Power Supply mode. If any of the above 3 points are changed, the voltage quickly drops back down to the set point, as normal.
It seems like with VE.Smart connected the IP43 is entering some code section intended for Charging mode despite being in Power Supply mode, then getting confused about why the battery voltage isn’t increasing, and increasing its own output until stopping at the 2V cap.
Disconnecting the VE.Smart or lowering the IP43 voltage set point below the sensed battery voltage quickly fixes it (until the battery voltage drops…)
@mpvader Feel free to remote login to my install to test/verify this.
In this scenario, the chargers output was disconnected from the battery?
Or how was it possible for the voltage to rise to 15.2V while the battery stayed at 13.17V
If thats the case, then this behaviour is to be expected. The same thing will happen in charger mode, and with MPPTs and Orions for example. The cable compensation will saturate at Vbat+2V
You are feeding the device an external voltage through the VE.smart network, then thats the new point of reference (13.17V in your case).
The device then tries to raise that reference voltage to whatever is set as the target, in your example 13.2V, by raising its output voltage, but if theres no, or a bad connection, between the output of the charger and the battery, then the output voltage will rise to (reference voltage +2V) so in your example 15.17V
Yes, the battery is disconnected and the IP43 is placed into Power Supply mode. At that point it is supposed to output a constant voltage regardless of whatever the battery is doing. Including if it’s fully disconnected (this is straight from the manual).
The key here is it’s in Power Supply mode, which per the manual will output a constant voltage. It shouldn’t matter what the battery voltage is in this mode.
I think what you describe is likely correct, that is what’s happening internally. But I would argue that it is contrary to the manual and frankly does not make logical sense from a user perspective (in Power Supply mode).
The key is the missing physical connection between the charger output and the voltage reference. If the charger is part in a VE.smart network, then the voltage reference comes from that VE.smart network
I would like to note that a product should always(!!) only be configured for a VE.Smart network when its output is actually connected to the same battery as the product reporting the voltage sense in the VE.Smart network. An example that is a house battery bank and a starter battery bank where a charger connected to the starter battery should not be on the same VE.Smart network as a SmartShunt connected to the house battery bank. The starter battery bank and the house battery bank each need their own VE.Smart network for voltage sense to work properly on both batteries.
I will report the idea of disabling voltage compensation in power supply mode to the developers, but it can very well be that the fact that it is not a bug but a feature that it does compensate. The reason being that it allows voltage drop compensation, even in power supply mode in case the output wires are on the long side and a more current independent voltage level is necessary at the point down the wire. A SmartBatterySense could be used at that point to measure the actual voltage and when this is in the same network as the IP43 power supply, the IP43 will compensate for voltage drop over the wire.
