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Looking for a Victron Energy Guru. I have questions 🤔

I have several of those from the Schneider XW pro so I am good. I just didn't know if the Cerbo would keep track of SOC without the 7xx monitor

The Cerbo will not keep track of SoC by itself.

You indicated you have a smartshunt, right?



BMV-700 - basic battery monitor with display and control relay.
BMV-702 - 700 + temp sensor or aux monitoring like starter battery monitoring or midpoint voltage monitoring
BMV-712 - 702 + bluetooth and can act as a DC energy meter
Smartshunt - 712 minus display/control relay.
 
I dont know what im talkibg about and you want accuracy?🤦‍♂️ 🤷‍♂️🤣 Someone mentioned dongle and I said i have one. I don't, and I just figured that out as I didn't know about the other.

All I have in victron in the old system is the inverter, mk3 to configure it and the smart shunt. None of the other things we've talked about, is installed yet, some I have not purchased yet, like the GX.

Okay. You currently have no temperature sensor. Did you say you ordered one for the MP?
 
The Cerbo will not keep track of SoC by itself.

You indicated you have a smartshunt, right?



BMV-700 - basic battery monitor with display and control relay.
BMV-702 - 700 + temp sensor or aux monitoring like starter battery monitoring or midpoint voltage monitoring
BMV-712 - 702 + bluetooth and can act as a DC energy meter
Smartshunt - 712 minus display/control relay.

Yup, 3 of them actually... One per series pair of 12v to get 24v, and one between the battery bus bar and the inverter. The series ones are set to monitor midpoint voltage and the big one is using a temp sensor on the bus bar just for fun. Two of the 300a and one 500amp.
 
@Craig Castleberry

Is this correct?

Current Equipment:

Multiplus II 12v 3k 50 120x2
Temp sensor for MP
Smart Shunt 500
4 Litime 230AH (920 AH) 12v configuration.
MK3-USB adapter

Planned additions:

Cerbo GX/touch
3,350 watts of solar, running 2 separate strings
Two Smart Solar MPPT 250/100 chargers.


If that's the case, the MP temp sensor connected to the T-sense terminal will supply the MP-II the appropriate temperature reading to use the MP-II's low temp charge protection feature. It can also be used as the system temperature for when you get a cerbo to feed temperature data to the MPPT.
 
@Craig Castleberry

Is this correct?

Current Equipment:

Multiplus II 12v 3k 50 120x2
Temp sensor for MP
Smart Shunt 500
4 Litime 230AH (920 AH) 12v configuration.
MK3-USB adapter

Planned additions:

Cerbo GX/touch
3,350 watts of solar, running 2 separate strings
Two Smart Solar MPPT 250/100 chargers.


If that's the case, the MP temp sensor connected to the T-sense terminal will supply the MP-II the appropriate temperature reading to use the MP-II's low temp charge protection feature. It can also be used as the system temperature for when you get a cerbo to feed temperature data to the MPPT.
No touch, going to use a tablet or the phone. Other than that, it's correct. 👍

I have the solar panels in the garage. Litime sent me a battery with a bad BMS so I just got the batteries and inverter back up today, but have a few things to finish up.
 
Personally I’d go Bluetooth dongle and ditch the cerbo if you aren’t going to do a touch display. Not a fan of the cerbo tablet integration.
 
I have several of those from the Schneider XW pro so I am good. I just didn't know if the Cerbo would keep track of SOC without the 7xx monitor

As I recall on my old system, there was a cable between the Cerbo GX and the BMV-712. I think it was a VE.Direct cable and it plugged into the back of the display. It did not plug into the shunt.

I had the BMV-712 before I adding the Cerbo GX and Touch 50. When I installed those two, I tucked the BMV-712 display into some dead space in a cabinet and never saw it again.
 
As I recall on my old system, there was a cable between the Cerbo GX and the BMV-712. I think it was a VE.Direct cable and it plugged into the back of the display. It did not plug into the shunt.

I had the BMV-712 before I adding the Cerbo GX and Touch 50. When I installed those two, I tucked the BMV-712 display into some dead space in a cabinet and never saw it again.
I'm figuring out the temp sensor is for the display and not for the gx. I just wanted the temp sensor and not the display.

I'm trying to figure out how to stop the solar chargers from charging when it freezes.

@sunshine_eggo said the sensor from the MultiPlus-II will work. Hopefully we have it figured out.

Thanks!
 
I think if the solar charge controllers don't have access to an external temperature reading, they use an internal temperature reading.
 
I think if the solar charge controllers don't have access to an external temperature reading, they use an internal temperature reading.

No it works with the Bluetooth smart Battery sensor .
It works with the Bluetooth smart shunt with the bmv702/712 temperature sensor .

The moment you go for a gx unit .
The battery smart sensor you can not use .(Its in the Manuel)
Really the moment you go gx systeem you can not use the Bluetooth function to the mppt.
The gx unit thake normal the systeem over and need its own data input to work.
A gx systeem do not use bluetooth from sensor the shunt or battery sensor.

If you set gx unit only for read out than you can .
Its function only like a watch to tell the data.

For the rest no Victron mppt do not have beult in temperatuur sensor.
Only the pwm unit have one .
 
See the last line in the screenshot below. This is direct from the Victron datasheet.

To my knowledge, that MPPT internal temperature sensor has no interface to the outside world.
It manages the MPPT circuit only.

Have you ever seen an MPPT temperature on VRM or victron connect?
I really hope I can be proven wrong on this one, because it is disappointing.
 
See the last line in the screenshot below. This is direct from the Victron datasheet.

View attachment 259225
Again
No it have not .
It only have for protection the unit it self .
And you can adjust manuel the temp for lead battery .

You need the Bluetooth battery sensor for the real temperature or a smart shunt for it.

See attach files .
1e picture demo from the 100/20 48v model
2e picture demo the warning wat you need .
3e picture is my own 100/20 48v with a bluetooth battery sensor.
Only on the 3e picture you see the temperature.

The Manuel explain it.



the internal temperature sensor of the MPPT is only for temperature compensation (primarily used for lead acid batteries) and cannot be used to trigger the MPPT to shut off in case of low temperature.

To make the MPPT shut off in case of low temperature of your Lithium battery you can set up a VE.Smart Network, connect your MPPT and at least a Smart Battery Sense or a BMV with temperature sensor to the same network, so that the MPPT gets the temperature reading directly from the battery.

See also the manual for Low Temperature cut-off, Page 21
 

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To my knowledge, that MPPT internal temperature sensor has no interface to the outside world.
It manages the MPPT circuit only.

Have you ever seen an MPPT temperature on VRM or victron connect?
I really hope I can be proven wrong on this one, because it is disappointing.
Victron do not.
A lot of other brand the same way .

Only some mppt have cable connection for external temperature sensor.
Problem the cable is to short for use and you can only use it if the both battery and mppt are in the same place.
You can not make that cable longer.
So its useless if your battery is away in a other room

The Victron mppt is easy .
You can be max 10 meters away thanks to the Bluetooth function.
Or if you use a gx systeem that have a temp sensor by the shunt.
And the gx unit is in active mode to adjust the systeem .
The mppt is op that moment control by the Victron gx brain.
Thanks to the VE systeem , cable you can easy go up to 100 meter.
 
I corrected your incorrect statement that there is no internal temperature sensor. There is an internal temperature sensor. It may not be available easily, but Node Red can access that register.
Not direct out of the box .
Than it will not work.

Oke if you like to try and diy to try that sensor to work .
But i do not read it can be used for shutdown.

Than again you need a gx unit or PI unit to let it work.
With out it

The mppt will not use it and only works with shunt with temperature sensor or the battery smart sensor.
To shutdown the charge .

 
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I remember reading somewhere the internal temperature sensor only uses the temperature it reads at the start of the charging cycle so it can't make adjustments if the temperature changes. Plus, what good is a temp sensor on the charger if the batteries are in a different place?
 
I remember reading somewhere the internal temperature sensor only uses the temperature it reads at the start of the charging cycle so it can't make adjustments if the temperature changes. Plus, what good is a temp sensor on the charger if the batteries are in a different place?

It's definitely of limited use. I was simply pointing out the incorrect statement that there isn't an internal temperature sensor.

In my old system, the two 100/50 solar charge controllers were in a network that used the temperature reported by the BMV-712. Since I had a warming system on the LiFePO4 batteries the only time the solar charge controller needed to worry about the battery temperature is if the warming system had failed or the operator had failed to turn it on.
 
It's definitely of limited use. I was simply pointing out the incorrect statement that there isn't an internal temperature sensor.

In my old system, the two 100/50 solar charge controllers were in a network that used the temperature reported by the BMV-712. Since I had a warming system on the LiFePO4 batteries the only time the solar charge controller needed to worry about the battery temperature is if the warming system had failed or the operator had failed to turn it on.
I think a mis communication.

Thare is a temp sensor but not for use to shutdown charging .
Its for the mppt it self to use.

This is wat i have told.

(No it have not .
It only have for protection the unit it self .
And you can adjust manuel the temp for lead battery .)

Sorry about that .
 
For anybody that missed it:

If that's the case, the MP temp sensor connected to the T-sense terminal will supply the MP-II the appropriate temperature reading to use the MP-II's low temp charge protection feature. It can also be used as the system temperature for when you get a cerbo to feed temperature data to the MPPT.

And yes. MPPT in-built temp sensor is mostly worthless. It uses a "snapshot" temp at startup before its own internal heating can influence the temperature sensor, and it behaves as though it's that temperature all day.
 
I'm figuring out the temp sensor is for the display and not for the gx. I just wanted the temp sensor and not the display.

I'm trying to figure out how to stop the solar chargers from charging when it freezes.

@sunshine_eggo said the sensor from the MultiPlus-II will work. Hopefully we have it figured out.

Thanks!

The same temperature sensor is used on:

BMV-702
BMV-712
Smartshunt
 

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