I have a Cerbo GX MK2. I believe I need to use its digital inputs but I have difficulties wrapping my head around the concept. I have read the manuals and other resources but I’m still having difficulties to understand how to cobble everything together.
What I need to achieve: Read if my 2 external external AC circuits, A and B, have AC voltage on them. Switch according to their respective states. If B has AC voltage while A has no AC voltage, send a “1” signal. In all other situations, send a “0” signal. I don’t need to measure the actual value of the AC voltage on each circuit, just that it’s present or not.
What I understand so far: The Cerbo has 4 digital inputs, I only need 2. Each Cerbo input takes up to 12v DC, so I would need an appropriate power supply or optocoupler on each circuit, before I go into the Cerbo. But how do I then generate an output signal from the Cerbo and how do I read it? Do I need another device to read and interpret the signal or a Cerbo relay can read act on such a signal?
I plan then to use an external relay to switch my AC or DC load (a simple LED light) on or off.
Does this sound correct or I can even simplify it?
Will I need additional hardware? What do you recommend?
If you download the Large firmware in the Venue OS, you will be able to turn on NodeRED and can program the functionality you require. It should be fairly trivial to test the 2 inputs and feed that to the relay state. The hardest bit with be making the input circuit to covert the AC to DC.
@pau1phi11ips I fully agree that using Node Red can be an easier solution. I already use it for other stuff. For this particular project, I wanted to stay away from it, but I can look into it deeply if it’s the only practical route to go.
Thinking about Node Red as an alternative (I still prefer not to use it), I could use it to read AC Out 1 of the Quattro and AC-In 2 (grid) and switch a Cerbo relay accordingly.
I was thinking about this a little more. I think the same thing can be achieved more simply. Nothing tested yet, just an idea.
I could use a programmable assistant in the quattro to read AC in and also AC out to switch a Quattro relay accordingly. I could use a proxy of AC Out, such as battery voltage, if needed to determine if that output is live or not.
Youre trying to see if an AC circuit is powered, without the need to know if the voltage is in an acceptable range?
Simply use a regular relay with an AC coil. Power it from the circuit you want to surveil. If theres voltage, the relay will be on, if theres no voltage the relay will be off. No need to do complicated things with the cerbo.
If you also want to check if the voltage is within a certain range, use a voltage monitoring relay instead
True @chrigu . But I need to monitor two separate circuits, which may be on or off, not necessarily at the same time, and then process the states of both to act. Can this be achieved with your suggested approach?
Just use a relay each. If i understood correctly you want to switch an LED, i guess LED on if both voltages are present, and LED off if one or both voltages are absent. Thats a classic AND logic. You wire both relay NO contacts in series.
AND is shown with three inputs here, bit works the same if you leave one out
@chrigu There is a small but significant twist: I want to power on the LED when the grid circuit has voltage AND the inverter circuit has no voltage. Otherwise, power the LED off. I can power the LED with the grid circuit or yet a third circuit.