Help with victron cerbo/mppt load output

[EvanC]

So I have a victron 100/50 wired to 4x200w panels on the roof of a trailer, and also a 100/20 controller installed to use for a separate ground panel or two. These are both connected to a cerbo s gx/starlink for remote control and monitoring.

I have roof mounted floodlights that I would like to control in what victron refers to as "Streetlight function", lights come on after dark utilizing PV voltage as the clock. Total lighting circuit power consumption will be a little less than 10 amps @ 12v.

The 100/20 has a physical load output connection, whereas the 100/50 load output is via the Tx port I think (part of the VE direct port?). My roof panels are wired 2s2p and come through the roof into one double pole breaker, then onto the 100/50. Currently, the lighting circuit is wired to the 100/20 load output connection and working well, but in order to sense night time (pv voltage from roof panels), I have to tap into the output of my roof panel breaker and wire into the 100/20 PV input terminals. This obviously negates the intended use of the 100/20, and currently the charging function of the controller is disabled, so I need a non 100/20 load output solution for powering my lighting circuit.

I have searched this forum as well as victron community with no luck, which is very surprising to me honestly. Also have combed through the cerbo gx s manual and 100/50 manual.

Is there a way to have my 100/50 load output control my lighting circuit via the same streetlight function via a cerbo relay?

If not, what physical hardware am I looking for for a non-smart solution? Some type of relay + contactor that will sense voltage from my roof panel breaker and then send power to the lighting circuit? I know this can be done, but I don't know what specifically I need.

Any help would be appreciated, thanks.

 

[sunshine_eggo]

This might help you:

 

[sunshine_eggo]

This might work too:

https://www.amazon.com/Proshopping-Photoelectric-Photocell-Photoswitch-Hard-Wired/dp/B082FBFD8Y

 

[EvanC]

This might help you:

Thanks for the link.

Unfortunately that won’t work for my application as both 100/50 and 100/20 VE direct ports are occupied with communication cables to the cerbo.

 

[EvanC]

This might work too:

https://www.amazon.com/Proshopping-Photoelectric-Photocell-Photoswitch-Hard-Wired/dp/B082FBFD8Y

Right right I was just looking at these. I think some type of hardware solution like this will be the direction I’m headed in. The only thing I don’t like is that I would have to run yet another wire to outside of the trailer for this. Would be great to tap into my pv shut off breaker as the voltage source, and utilize the roof panels as my “photocell”, ya know?

 

[Q-Dog]

How about mount a small panel connected to the 100/20 with a selector switch to change from the small panel to the portable panels when you deploy them?

 

[sunshine_eggo]

Right right I was just looking at these. I think some type of hardware solution like this will be the direction I’m headed in. The only thing I don’t like is that I would have to run yet another wire to outside of the trailer for this. Would be great to tap into my pv shut off breaker as the voltage source, and utilize the roof panels as my “photocell”, ya know?

Given the wiring diagram, it looks like you could just put it in series at some point in the circuit. Splice device (-) to the battery side (-), cut the (+), connect cut (+) from battery side to device red, connect device white to the other cut (+).

 

[EvanC]

Thanks for the suggestions.

Well I gave up on a non mppt solution and just ordered a used smartsolar 75/10 controller. Going to build a small enclosure for it plus a couple other electrical things that need a better home.

I'll just use the other two controllers for their specific purposes, and tap off my roof panel breaker into the 75/10 input, and then disable the charger. That way I can still control the circuit from VRM/my phone too.