We build solar lighting systems using Victron SmartSolar MPPT 75/15 and want to make sure our current controller setup process is correct before we scale it to more systems and ship out of state.
Our current setup process is: hook up the SmartSolar controller to a 12V battery, import a standard settings configuration (locking it into 12V), then unplug the controller from the battery. From there, we’ll connect PV & load (in either order) to the controller to prepare it for shipment. Finally, when on-site, the customer will connect the controller to the battery which will power the system on.
The manual states that the order for wiring is battery, then load, then PV. However, if the voltage is manually set (to 12V for example) prior to hooking up PV & load, then wire order doesn’t matter.
Does anyone have any experience with this? We are hoping to have PV & load pre-wired prior to arriving to customers, with them only being responsible for connecting the controller to the battery.
Not true.
The rationale for the power order is to allow the inverter side to power up and stabilise before a load is added. However, it may be ok though not recommended to start the inverter with a load connected.
If the PV is connected before the battery, then the input voltage to the inverter is not properly stabilised, and may cause damage to the inverter.
There is no reason not to pre-wire load and PV as long as you include switches that allow disconnection - these should be part of a good design anyway.
I don’t think Josh has an inverter anywhere in the system, sounds like only DC to me.
In my experience: If you power up the controller from solar, the battery terminals will go to the float voltage almost immediately, the yellow float light will illuminate, and if you have preset the battery type and voltage, the battery terminals will be at the correct float voltage.
When you connect a battery, the voltage delta will be small (float voltage, vs Vbat) so the spark will be small.
I see no problem with this method, I’ve used it many times.
ok with just the small MPPT units there should not be a problem - The 75/10 I know will survive this - it is intended to be able to ‘start’ a lithium battery BMS which has gone into battery protect mode, so no output voltage.