Quelle/Ursache eines Temperaturalarms? RemoteKonsole

Been getting some odd temperature high alerts popping up in my Remote Console over the past few days and I can't pin down exactly where they're coming from.

Running a Multiplus-II 5000 with a 24kWh Fogstar Drift lithium bank — four packs connected via CAN using JK BMS units (v19 firmware). Everything's been rock solid for months, but since the warm spell last weekend the alerts have started appearing intermittently. Not every day, not at any predictable time.

Few things I'm unsure about:

• Is the alarm being triggered by the BMS reporting a cell temp to the Victron, or is it the Multiplus itself getting warm?
• How do I tell which device is actually the source in VRM or the Remote Console? The alarm just says "temperature high" with no obvious pointer to which pack or which unit
• Could it be one rogue BMS pack running warmer than the others and pulling the whole system into alarm?

The battery shed isn't insulated brilliantly and we've had a few days pushing mid-20s inside — not extreme by any means, but warmer than usual for up here in the Pennines.

I've checked VRM history and the alarms clear themselves after an hour or so, no charge interruption that I can see. Victron firmware is current on the MP2.

Anyone had similar with JK BMS packs over CAN? Is there a reliable way to identify which device is throwing the temperature flag, rather than just seeing the generic alarm in the console?

Good shout checking the Remote Console logs rather than just dismissing the alerts. On my Multiplus-II setup I found the temperature alarms were actually originating from the BMS temperature sensors rather than the inverter itself — easy to confuse because they all bubble up into the same alarm feed.

In VictronConnect (or Remote Console), go to:
Device List → [Your Battery] → Parameters → Alarms

This'll show you which specific sensor is triggering — cell temp, FET temp, ambient, etc.

Also worth checking your Venus OS device logs under Remote Console → Diagnostics. The alarm history timestamps can help you correlate it with high load events or overnight charging cycles.

What BMS are you running with that 24k? If it's a Seplos or JK, there are known quirks with how temp thresholds get reported over CAN.

Good timing to investigate this before summer properly hits. @PennineSolar, one thing worth checking is whether the alerts correlate with times of heavy inverter load - my Multiplus-II 5000 runs noticeably warmer when I'm pulling close to its limits for extended periods. Also have a look at the physical ventilation around the unit itself; even a bit of dust buildup on the cooling fins can cause temperature spikes. In the Remote Console, go into the device list and check if the alert is flagged against the Multiplus specifically or coming from somewhere else in the system - that'll help narrow it down considerably before you start chasing your tail. What's your ambient temperature like where the unit's installed?

@PennineSolar the alert source is usually identifiable in the Remote Console under Device List — each device shows its own alarm status separately, so you can see whether it's originating from the Multiplus-II itself, the MPPT, or the BMS if you're running a managed battery.

On my setup (Multiplus-II 3000, Victron SmartSolar, Fogstar Drift 24V battery) I had similar alerts that turned out to be the inverter's internal temperature sensor rather than the battery. Worth checking the VEBus device entry specifically.

Also worth ruling out: is your Multiplus-II in an enclosed space? Ventilation is often overlooked. Victron's recommended minimum clearances are larger than people expect — 10cm either side minimum, ideally more above.

If you can share a screenshot of the Device List during an alert, that'll narrow it down considerably.

@PennineSolar worth checking whether the alert is tied to the Multiplus-II internal temp sensor or your battery BMS. On my narrowboat setup I had similar ghost alerts that turned out to be the Cerbo GX logging ambient temps from a poorly positioned sensor near the engine bay — nothing actually overheating.

In Remote Console go to Device List → your Multiplus → Parameters and look at the actual temperature value being reported. If it's spiking momentarily then settling, could be a loose connection on the temp sensor rather than genuine heat buildup.

Also worth checking the VE.Bus System entry separately — sometimes the alert source displays there rather than directly under the inverter. What's the ambient like where your 24k battery bank is sitting? Fogstar or similar LFP cells can throw BMS temp alerts if airflow is restricted.