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Streetlight function on Smartsolar MPPT 250/100

I have a Smart solar 250/100 Charge controller for a 48V battery system . my loads are flood lights which are above 4kW .
since this controller does not have a dedicated load output terminals so I am using external relays . I want to use the relay port on the charger to drive the load external relay. recently I came to know about street light function inside victron app but I am not sure about its real used-case scenario.

Can anyone guide me whether I can use this function to drive the relay port on the charger which can then trigger the external relay that will turn the load circuit on . My aim is drive my 4KW load at night time only and also take care of battery capacity too .

MPPT ControllersMultiPlus Quattro Inverter ChargerStreetlight
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1 Answer
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wkirby answered ·

Yes, you can use the relay contacts of the MPPT relay to switch the coil current of a following relay.
The specifications for the relay contacts inside the MPPT are in the datasheet:

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thank you for the confirmation . Can you also tell whether streetlight function can be used to this programmable relay inorder to turn my loads to be on at specific sunset / sunrise times?

I do have quatro connected in my system along with these charge controllers . so in theory does that mean solar chargers with the help of streetlight fn and relay setting will allow the battery voltage be available at the Quatrro end inorder to run my loads?

You cannot define specific times for sunset / sunrise because there is no clock in the MPPT. Sunset / sunrise is estimated by the output from the solar panels.

Are you suggesting to switch the Quattro on and off by its DC cables? If so, do not do that. Much better to use an Aux input "Safety Switch" Assistant to switch the Quattro On or Off with a small signal relay.

Can you please provide any eg for a reference so that I can follow that and use the street light fn of these charge controllers?

I have AC loads (lhuge lamps) to be run so of course Quattro is the one going to invert that but I want these lamps to be turned on only during the night time and also take care of battery capacity too. so when to my understanding when its sunrise time , then inverter shouldnt allow to invert and supply power to loads since they are lights.

Am I thinking all this wrong that this virtual load output is offered by the mppt charger in the form of relay right ? so it will allow the load to be run based on streetlight logic and since loads are AC in mycase then there is no way they can be run without being inverted by the Quatrro.

Please correct anything that you find wrong here. I have got massive loads to run based on times of day / night and also taking care of battery life and I would really appreciate your help .

Yes, the streetlight logic can be used with this charge controller.

Sunset / sunrise detection is set up my the PV panel Voltage limits. When it gets dark enough then the relay can be activated. When the sun comes up again then the relay can be de-activated, set by PV panel Voltage detection.

Sunset and sunrise is by PV panel Voltage, not specific time of day. Sunset and sunrise is probably better anyway. Summer the floodlights will switch on later and switch off earlier than winter time when the night is longer.

You can use the MPPT relay contacts to drive the AUX input of the Quattro to enable and disable the Quattro. Use the Assistant in the Quattro for enable and disable.

Earlier on I was saying not to interrupt the Quattro's DC cabling. Use the AUX input to enable and disable the Quattro.

I think I have not fully understood the use of aux input on Quatro as there is no detail explanation in the tech manual. is it possible send you an email and get some help on this please ?

Yes I do want to use the aux input for some other reason but the issue is that ESS settings say that you have to disable VS (virtual switch) in VEConf sw which eventually eliminates the use of aux there.

The product manual does not cover the use of VE.Configure which has its own manual. There is also a link to the assistants manual in there:

You don't need VS, so you can leave it off. You just need to use an Assistant called "Safety Switch". When MPPT relay contact opens (sunrise) then the Quattro will be switched off.
If you are using Aux1 input already then you can use Aux2 input instead.


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thanks for sharing the link , so this aux port is this used to read digital input ? btw for switching off inverter based on mppt controller what should be wiring schematic between aux and charge controller here?

morever I was wondering to add an emergency stop button in my system so if someone presses it . I would like to have no inverter operation to happen as in an emergency state . Can I achievd this using aux?if yes , please guide a little

I am alreadty using mppt relay for triggering my load circuit relay so is there any other option to overcome this? so I can turn off inverter based on mppt signal?