Victron Cerbo GX (RPi) HELP...

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Have just installed my Cerbo (Raspberry Pi) in the M/H...

First thing I did was connect the Smart Shunt via a Victron USB cable. It immediately displayed on my touch monitor and through VRM.

But... Now VRM is showing a constant discharge and circa 3 days remaining (and falling), despite the Victron Blue Smart IP22 being hooked up to mains and the battery voltage holding steady at 13.6V.

Previously, via Victron connect, when all was wirelessly networked, when on EHU it would display an infinite time remaining once a full charge was achieved.

Am I missing some VRM settings somewhere?

Appreciate the Blue Power IP22 doesn't have VE direct, but surely the smart shunt can see a current flow in both directions?

The voltage is holding steady at 13.6V and the Blue Smart IP22 drops in and out of float/storage mode as normal, but the shunt is constantly showing a discharge, which isn't true.

Any thoughts anyone?
 
Have just installed my Cerbo (Raspberry Pi) in the M/H...

First thing I did was connect the Smart Shunt via a Victron USB cable. It immediately displayed on my touch monitor and through VRM.

But... Now VRM is showing a constant discharge and circa 3 days remaining (and falling), despite the Victron Blue Smart IP22 being hooked up to mains and the battery voltage holding steady at 13.6V.

Previously, via Victron connect, when all was wirelessly networked, when on EHU it would display an infinite time remaining once a full charge was achieved.

Am I missing some VRM settings somewhere?

Appreciate the Blue Power IP22 doesn't have VE direct, but surely the smart shunt can see a current flow in both directions?

The voltage is holding steady at 13.6V and the Blue Smart IP22 drops in and out of float/storage mode as normal, but the shunt is constantly showing a discharge, which isn't true.

Any thoughts anyone?

Post a photo of your touch screen and Victron Connect that might help us see what's going on.
 
Post a photo of your touch screen and Victron Connect that might help us see what's going on.
Screenshot_20250521_184551.webp


20250521_184754.webp
 
Enable in GX settings " has DC" so we can see if that is positive or negative

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Does the battery charger negative cable got to the shunt, or directly to the battery?

Do you have any 12v loads switched on because the shunt does seem to think 4.5amps (or 5.2) is going out?

The start battery voltage is 13.1v so I guess the engine or some other charger was recently charging the start battery, since rested it should be around 12.7/8v? Unless your van has a trickle charger for the start battery?

Given the low amperage of the charger output I'm not sure why the charger reports 13.9v output, but the battery seems to be at 13.6v.

Not much help I'm afraid.....
 
First question is, do you have all your van 12v circuits, that being your circuits that discharge and all that charge at 12v going through your shunt. ?
Yes, everything goes through the shunt, directly after the battery, then into x2 bus bars. x1 negative & x1 positive. Everything 12V is then connected to the bus bars accordingly.
 
Does the battery charger negative cable got to the shunt, or directly to the battery?

Do you have any 12v loads switched on because the shunt does seem to think 4.5amps (or 5.2) is going out?

The start battery voltage is 13.1v so I guess the engine or some other charger was recently charging the start battery, since rested it should be around 12.7/8v? Unless your van has a trickle charger for the start battery?

Given the low amperage of the charger output I'm not sure why the charger reports 13.9v output, but the battery seems to be at 13.6v.

Not much help I'm afraid.....
Battery Charger negative cable goes to the negative bus bar.

No 12v loads switched on other than the Rpi and the M/H WiFi router, which should have a draw less than 0.5A max.

Starter battery is on a Van Bitz Battery master, so always sits 0.5v less than the fully charged leisure battery. Shut AUX connection is reporting this as you can see.
 
Yes, everything goes through the shunt, directly after the battery, then into x2 bus bars. x1 negative & x1 positive. Everything 12V is then connected to the bus bars accordingly.

Okay, Check what Raul said and that you have "Has DC System" on.

Edit ; Just seen that you posted at the same time as me. (y)

1747854948779.webp

1747854961596.webp
 
Ok, has DC system now on... now I get this... (this is the VRM overview). Apparently I am now at 95% and discharging, despite the battery voltage holding at 13.6V and the Victron charger being in float mode.

Untitled.webp
 
On the VRM if you select "Remote consol" from the drop down menu you can then click on the icons an see what's happening, like you can when viewing local.
 
Last edited:
On the VRM if you select "Remote consol" from the drop down menu you can then click on the icons an see what's happening, like you can when viewing local.

That's what remote consol is showing...

Untitled.webp
 
You can click on the shunt or charger to get more info like on the local screen.

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You can click on the shunt or charger to get more info like on the local screen.
If I click on the battery, bottom left of the local screen, there is no response. Only when I go into "devices" and then select the shunt does it give me more info, which isn't much more than I can see in the overview.

I don't have a charger linked to the GX, as it is an IP22 Victron Blue Smart, which doesn't have VE direct.

I would expect the shunt to see an incoming current from any type of charger, though it doesn't, it appears to see a constant discharge, even though the battery voltage remains constant (as it is being maintained).
 
If I click on the battery, bottom left of the local screen, there is no response. Only when I go into "devices" and then select the shunt does it give me more info, which isn't much more than I can see in the overview.

I don't have a charger linked to the GX, as it is an IP22 Victron Blue Smart, which doesn't have VE direct.

I would expect the shunt to see an incoming current from any type of charger, though it doesn't, it appears to see a constant discharge, even though the battery voltage remains constant (as it is being maintained).

To me, it points to the negative of the IP22 going to the battery negative rather than the shunt. ?
 
The IP22 negative goes through the bus bar negative, which in turn runs through to the shunt negative, then directly to the battery negative...

The only possible issue I have just seen here, is that I have run a large negative from the bus bar directly to the chassis, rather than from the battery negative directly to the chassis... (which is the cable you can see running along the rubber lining around the ply shelf in this image) Would that have an impact? Thinking logically I think it might...

20241129_131316.webp
 
Er... So checking my logic, by connecting the chassis directly to the negative bus bar, technically bypassing the shunt from metering everything, that could cause all sorts of odd readings...

Where is the massive slap in the face emoji when you need it :LOL:.

Will take that chassis cable out of the negative bus bar and connect it to the negative terminal on the leisure battery where it should be first thing in the morning.
 
There should only be one connection on the negative terminal of the battery and that is the shunt.

Any other connection to the battery will bypass the shunt.

Double check your shunt as it sounds like it's connected the wrong way round.

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There should only be one connection on the negative terminal of the battery and that is the shunt.

Any other connection to the battery will bypass the shunt.

Double check your shunt as it sounds like it's connected the wrong way round.

There is only one connection "currently" from the negative of the leisure battery going to the shunt, then out of the shunt to the negative bus bar.

But there is then a connection from the negative on the bus bar going directly to the chassis, where lots of cab battery connections are obviously negatively connected as per any vehicle (inc the Battery master).

Should the leisure battery negative not be directly connected to the chassis then? As, for example, the Battery Master shares a common negative with the starter battery & leisure battery.
 
Er... So checking my logic, by connecting the chassis directly to the negative bus bar, technically bypassing the shunt
No you didn't, the bus bar goes to shunt to the battery. It does not bypass it, it goes trough it to get to the battery
 
Will take that chassis cable out of the negative bus bar and connect it to the negative terminal on the leisure battery
No no no, that WILL bypass the shunt. Leave it be.
Check shunt direction and the correct end is at the battery not the other way.
 
What I would do, is make sure the shunt is the right way round: then, I would disconnect all the negatives load side. Confirm shunt current is 0, and add one at the time, starting with mains charger, and watching for changes to amps reading to the shunt. If all good move on to the next negatives. Add the chassis ground last and see if any draw is at the front, battery master etc.

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Should the leisure battery negative not be directly connected to the chassis then? As, for example, the Battery Master shares a common negative with the starter battery & leisure battery.
The negative to the chassis is already correctly connected if it goes to the negative bus bar, as you say. Then the bus bar should be connected to the load side of the shunt. The battery side of the shunt should be connected to the leisure battery negative terminal. There should be no other connections to the leisure battery negative terminal.

The only exception is if you have more than one leisure battery, and are wiring them in parallel. If you do that, the link wires between the batteries go to the battery terminals directly, not to the busbar or chassis.
 
The negative to the chassis is already correctly connected if it goes to the negative bus bar, as you say. Then the bus bar should be connected to the load side of the shunt. The battery side of the shunt should be connected to the leisure battery negative terminal. There should be no other connections to the leisure battery negative terminal.
So it's wired correctly then, thats good.

So here's where I am, the system has been installed for 3 months and has been working perfectly, I have been monitoring it (locally via victron connect bluetooth) when we have been away, both on EHU and Off-Grid.

The lowest SOC I have seen was 85% after a long night off-grid with everything lit up like an Xmas tree, the telly going and the inverter charging my E-bike (highest draw was around 14Amps). Battrry was back to 100% within a few hours of the sun coming up the next day (via 435w panel & Victron MPPT).

When on sites with EHU, the battery never fell below 100%, as the IP22 was covering the load.

When parked up on our drive it is always on EHU and the IP22 eventually drops into "storage mode" where the battery sits at 13.6v, with the battery master happily keeping the starter battery circa 0.5v below the leisure battery.

I then decided I wanted to have a play with RPi GX and Venus, all went well. Put the RPi in M/H and connected it to VRM via the M/H wifi router. Left it sitting disconnected from any VE hardware while I waited for the VE Direct to USB cables to arrive. The draw shown on the shunt locally via Connect was less than 0.5A with the Pi and router being the only things running and the IP22/MPPT were both in storage mode, just maintaining the battery at 100%.

VE Direct Cables arrived yesterday so I thought I would start with the shunt. Connected that to the RPi, was pleased that it showed up on the touch screen & via VRM, but suddenly I was now seeing a 5amp draw and the SOC dropping (even with the IP22 running).

Left it overnight last night, I now have an SOC of 79% and the 5Amp draw is still there (still on EHU).

It is as if connecting the GX has knocked out the IP22 and MPPT and created a 5amp draw from somewhere (which is very odd).

Am going to disconnect the Rpi GX this AM and revert to monitoring Connect locally to see if that then gets me back to where I was previously (inc the IP22 and MPPT charging the battery again).
 
Just put of interest I'd disconnect the battery master and see how the current changes.

It dropping as far as 79% is odd though.
 
Double check your shunt as it sounds like it's connected the wrong way round.
Have just triple checked against VE instructions and it's the right way round. Which would make sense as its been fine the last 3 months, happily reporting via Connect app & Bluetooth.

This only started when I plugged the shunt into GX via VE Direct cable.
 
There you go. :doh:
Have just triple checked against VE instructions and it's the right way round. Which would make sense as its been fine the last 3 months, happily reporting via Connect app & Bluetooth.

This only started when I plugged the shunt into GX via VE Direct cable.

When you made your VE.Direct cable up, did you only connect the rx, tx and ground wires and not connecting the red positive to the JST connector and crossed over the rx to the tx and the tx to the rx ?

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