Hello,
Situation: I’ve got an Inverter/Charger.
In the work truck sector, it’s very common to want an Inverter to turn on by sending a 12V signal to a terminal on the inverter that is ready and waiting for that signal. The source of this 12V signal is commonly one of the switches in a bank of “Upfitter Switches”.
I can do this with the Victron Inverting Remote On/Off cable (ASS030550120).
However, I want to be able to engage the Multiplus (or Quattro or MPII) charger when AC Input is provided WITHOUT needing this 12V signal. That’s where I’m stuck.
It seems like I should be able to use the built-in Multiplus or Quattro Programmable Relay with Logic based on “Do I have AC Input Voltage” (or any of the other built-in relays).
However I am finding that the Programmable Relay won’t kick in Unless/Until the inverter turns on. And that’s not how the operators will use the system. They get back to base, turn the Inverter Upfitter Switch off, go walk to the Shore Power pedestal and plug it into the truck.
The closest I have gotten is having the Inverter On with the Upfitter Switch (Inverting Remote On/Off cable) then I plug into shore power and the charger kicks in, and then I can Turn my Upfitter Switch off… The unit stays on and charging while AC is present and as soon as I unplug from Shore Power the Inverter does turn off and that is what I want.
Anyone know how to basically make the Inverter Accept the Shore Power whenever it is presented? With the inverter on or off, I want it to accept shore power.
Has to be easier than this. I hope I’m missing something simple.
It’s pretty easy with a cerbo GX and node-red. I can’t figure out how to use the relay assistant the logic is not there from what I can see and you have already found that out.
There is a node to check for AC in. If there is AC in it send a 0 no AC sends a 1. I have a function to look for a 0 and send a 3 or input is a 1 send a 4.
Other values for the switches are below. You will need to use the Upfitter Switch to disable this flow but will be easy enough to check the state of the digital input on the GX and disable it. If this is something you think will work I can help you.
Dont need any programming I already did it. Took 2 mins. I took me more time to look at the link to figure out how it wont it work. Still dont dont know how it will work.
I appreciate both of your “input” (pun intended, lol). I’ll remain in a holding pattern for now… the best solution (business-wise) would be completely under the Victron umbrella and many of my customers will not opt for the Cerbo price tag, and the installers we distribute to will not want to mess with Node Red (maybe someday… but not yet). ’
I wonder if @guystewart or @M_Lange would know if it’s doable at present?
Another idea I had was for Victron to add some functionality to the VE.Config software with a Check box in the Charger tab that we could select that forces the Inverter/Chargers to accept shore power whenever present, regardless of On/Off/Charge Only switch position or Inverter On/Off state. Not sure it’s possible, but the potential for Victron to infiltrate and grow dramatically into the North American Work Truck Sector is huge, yet this drawback is going to be a big hurdle even if it seems like a small one.
@M_Lange
We’re dealing with the 120V Multi plus 12/3000 UL and the Quattro 12/5000. I’ve been doing the testing with a Multiplus II 12/3000 UL. All 120V.
I don’t need it to work on the MPII. Mainly focused on the original MP and the Quattro.
And no, @Ludo, I can’t have the customers leaving the inverter on even in a power save mode. The vehicles sometimes don’t get touched for days or even weeks.
A normal relay should be small enough to fit into the MultPlus/Quattro and only one wire needs to be switched externally.
The system need a common ground.
If the switch is open the relay is off → the right and middle terminal of the remote are shorted → the device is in “charger-only”
If the switch is closed the relay turns on → left and middle terminal of the remote are shorted → the device switches to ON.
In “charger-only” the device is off until you connect AC IN, with AC IN connected the device will switch on and start charging the battery.
Thanks to both of you for your time on this. Good info. @M_Lange , I decided to use the relay built into the BMV-712 that will be in all these systems. I sent the 12V signal from the “upfitter switch” to the B2 terminal of the Shunt. I wired it the way you advised (NO on BMV to the left terminal of “H” & NC on BMV to right terminal of “H”, and COM of BMV to middle terminal of “H”).
In the BMV settings I setup B2 as a “starter battery” and used the Low Starter Voltage Relay with a “Set value” of 10.0V and a Clear of 10.1V… finally, I “Inverted” the relay.
It works… It’s in Charger only mode with no 12V signal being sent to B2 as intended and the inverter turns on instantly when I send the 12V nominal signal to the B2 port of the Shunt and the inverter turns off about 10 seconds after removing it (I don’t know why it takes 10 seconds… I have the Min closed time and relay-off delay set to 0 minutes but I’m ok with it. And actually it’ll help not drop the signal if the starting battery is weak and trying to be used to start the vehicle… if voltage drops below 10V during starting it’ll rise inside of 10 seconds once the vehicle does turn over and start running).
BUT,
I’m draining about 0.23 Amps with a MP continuously when in charger only mode (maybe more on a Quattro?). I know that doesn’t seem like much. But I’m trying to coddle these municipalities and Electric & Gas Utility customers and trying to help them avoid ever running a battery bank dry. I do provide them with a Battery Disconnect switch for the 300Ah or 600Ah Lithium battery bank and instruct them to switch it off if the vehicle will go unused for 2 weeks in a row or more.
For a 300Ah 12V battery bank, 0.23A constant draw = about 25% discharge over 2 weeks.
While not horrible, it’s more than I was hoping to see.
Again, I appreciate your input. I just have to decide if that amount of constant draw is acceptable.
We’re at the early stages of Lithium battery system adoption with these types of customers and they will screw it up (let a battery drain completely dead) if I let them… then they’ll complain that their old Sealed Lead Acid systems never drained like that (even if they did).
It would just be great if I could make the inverter turn On with a 12V signal with no extra relay at all and have it charge from shore power whenever shore power is presented, even if I have to move the 3-position switch to charger only when I wanted to charge.
With the relay concept, or the Inverting Remote On/Off cable, I can’t even setup it up to turn the inverter on with the 12V signal and charge when I move the 3-position switch to Charger Only and present shore power.
It’s kind of annoying that none of the input terminals in the MP & Quattro can be re-appropriated to receive this 12V signal to turn the inverter on without adding another separate relay. All of the Ultimate Power brand Inverters can do this and a Dimensions NP (Inverter/Charger) charges whenever shore power is presented, without having to flip any switches (and it turns the inverter on by sending this 12V signal to the Remote Switch male faston terminal).
