Tell us the alarm name or code, how many batteries you have, and whether they were all installed at the same time. With your permission we review your Fox Cloud alarm history, battery data and firmware version.
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Excellent support. He is extremely knowledgeable and his experience is second to none. I have GivEnergy equipment and he sorted out my solar problems remotely. He was understanding and patient and excellent to deal with. Would highly recommend. Thank you
I received a prompt response and excellent technical support for the remote diagnosis (Oxfordshire) and resolution of my GivEnergy EMS configuration. My GivEnergy issue involved a single inverter and battery that had a loss of calibration, a critical low voltage drop. It needed a recovery and re-calibration, and was supported via email into yesterday evening being resolved within 24 hours. Ron demonstrated a very high level of knowledge and experience in the intricacies of a GivEnergy EMS configuration, even surpassing the understanding of GivEnergy itself when it was still operational. I have already recommended their services to a neighbour as I’d be happy to use their services again based on the fair pricing and the quality of their support.
Had a problem with my GivEnergy battery which seemed to be a calibration issue. My installer was unable to help so contacted Ron at Solar Tech Support who was immensely helpful. He diagnosed, confirmed and fixed the problem remotely and very speedily. Would thoroughly recommend this company for their knowledge and ability.
Very speedy response. Handled by a real human who took my system through a logical process with the desired outcome within minutes of them accessing my inverter settings. Ron passed me on to Ash, they are both ex-Givenergy people who clearly know their stuff and can give the reassurance of proper technical support now that the Givenergy support desk has closed. A worthwhile investment in ensuring my expensive kit is kept fully functioning.
My GivEnergy Solar/Inverter/Batteries system went down and the GivEnergy Administrators are totally non- existent/useless. Luckily, I found Ron, who used to be a GivEnergy Installer, and beyond my wildest dreams, he sorted everything out remotely from 200 miles away. His approach to everything is very professional and I cannot recommend him more highly. Thanks very much Ron!!
Absolutely wonderful support. I have a GivEnergy system that was installed in 2022, and a firmware update was flagged in the app, so I proceeded to update the software .... and immediately regretted it, as my inverter came up with an error, and was not working at all! With no GivEnergy support available, and my installer saying there was nothing he could do, I googled help, and found Ron. What a stroke of good luck! Submitted an on line enquiry late morning, and received phone call just after 5 pm, and later that evening Ron was able to supply me with old firmware no longer available on the GivEnergy web site. I was then able to update the firmware using a GivEnergy youtube video as reference, and hey presto the system was back up and running. One further slight adjustment by Ron and we are back normal. What a relief. I have no hesitation in recommending Solar Tech Support if you have a problem. Great service! And if you are a GivEnergy system owner, whatever you do, DO NOT UPDATE FIRMWARE!
Open Fox Cloud and check the alarm history for BMS Lost (code 14), Bms Ext Fault or Bms Int Fault. Note what the app and the inverter's screen show for the battery, and whether the battery is charging or discharging. Also count the battery modules in your system and tell your installer or us. Do not open the inverter or disconnect any DC cabling yourself.
The inverter still reports in Fox Cloud, but the battery shows as offline, has no charge reading or has a BMS alarm. You are on the right page: start at step 1 below.
Fox Cloud has stopped updating for the inverter as well. That points to the monitoring link, not the battery. Check the inverter's own screen, then see Fox Cloud offline.
Work through these steps in order. Step 1 confirms the alarm. Steps 2 and 3 cover the DIP switch and the cable, which are a job for your installer or an engineer. Steps 4 and 5 cover battery versions and firmware. Step 6 is a full restart.
Open Fox Cloud and check the alarm history. The alarms to look for are BMS Lost (code 14) and Bms Ext Fault, which both mean communication between the battery and the inverter is interrupted. Bms Int Fault means communication between battery packs is interrupted, or a DIP switch is in the wrong position. Bms ChgReq NoAck (code 222) means there was no response to a charging request. Fox ESS's manuals list these alarms by name, and Fox Cloud also shows a number, in its own wording. Those manuals have no alarm called "BMS warning". Next, check whether the battery has stopped charging and discharging; the app may show it as offline or without a charge reading. On the H1-G2, the red light means a fault and the blue light means the inverter is normally connected to the battery. Note whether the alarm is constant or keeps coming and going, and tell your installer or us.
A DIP switch in the wrong position is one of the causes Fox ESS's manual lists for the Bms Int Fault alarm. On the HV2600, the DIP switches sit on the BMS BOX and show how many HV2600 modules are in the system. Fox ESS's ECS manual describes no DIP switch. Setting it is a job for your installer or an engineer: do not open the battery or the BMS BOX yourself.
The inverter's BMS port connects to the battery with the BMS lead supplied with it, or with a standard network cable crimped with an RJ45 plug to the pin-out in Fox ESS's manual. On an ECS battery it goes to the CAN port on the master module (the CM). On an HV2600 it goes to the CAN port on the BMS BOX. Fox ESS's action for BMS Lost is to check this cable is correctly and securely connected. If the ECS battery's lights look normal but the inverter's screen shows no charge reading, Fox's ECS manual says to check the link, then replace the cable. Your installer or an engineer does this: do not unplug or re-seat the cable yourself.
Some Fox ESS batteries (the HV2600, ECS2900 and ECS4100) come in version 1 and version 2, which you tell apart by the serial number. Fox ESS says supply changes between versions have caused compatibility problems. Mismatched battery software raises its own alarms, such as Bms Ver Unmatch and Bms M&S Unmatch, and Fox's action for those is to contact the battery supplier. Your installer is Fox ESS's first contact for owners. Fox ESS UK service (service.uk@fox-ess.com) can supply inverter firmware on request if you give the inverter serial number, and STS can also look at it with you. After a battery change, a firmware mismatch can also show as code 240 (CT or meter not detected): see this worked example.
On the H1-G2 display, go to About and choose Inv Ver for the inverter's Master, Slave and Comm versions, or Bat Ver for the battery. Fox ESS's public release notes list Master V1.51 (13 Jan 2026) as the latest for the H1-G2, and they do not say it fixes communication faults. The one fix in those notes that names battery communication is for the H3 Pro (Manager V1.44). Owners can't update the inverter's firmware from their own Fox Cloud login: it needs an installer-level account, or a request to Fox ESS UK service with the inverter's serial number. Fox advises updating only when the system is stable. USB updates are a job for your installer or an engineer, and battery firmware goes through Fox ESS UK service.
If the alarm is still showing and you want to try a restart, restart the whole system once, not one device. Our order for a Fox ESS system is the battery's power button first, then the AC isolator, then the inverter's DC isolator, and the battery's DC MCB last if it has one, so the MCB is never switched under load. To turn it back on, go in reverse: battery DC MCB, DC isolator, AC isolator, then the battery's power button. Read the full shutdown guide. Check in Fox Cloud whether the alarm has cleared. Fox ESS's action for BMS Lost is the cable check in step 3, not a restart, so if the alarm comes back, stop there. Contact STS for a remote diagnostic and with your permission we can review your Fox Cloud alarm history and battery data.
Fox ESS's manuals give Bat Volt Fault, Bms Volt High and Bms ChgCur High their own actions, separate from the BMS Lost cable check. Checking battery voltage is not an owner step: note the alarm and the time, then contact your installer or us. If the battery itself has failed, Fox ESS UK's policies say your installer makes the warranty claim. If your Fox ESS installer has gone bust, we can be the Local Installer you appoint to make the claim. How we make a Fox ESS claim.
Fox ESS calls this a battery voltage fault. Its action is to check the battery input voltage is within the normal range, or contact Fox ESS. An engineer makes that check, not you.
Fox ESS calls this battery over-voltage, and its action is to contact the battery supplier. Owners report that a battery firmware update ended repeats of this alarm.
Fox ESS calls this battery charge over-current, and its action is to contact the battery supplier. Fox Cloud's alarm table lists 195 as charging over-current, though one owner reported it as a battery voltage fault.
Owners report this code with battery faults, and Fox ESS publishes no meaning for it.
The Fox ESS H1 and H1-G2 inverters communicate with Fox's batteries over a communication cable plugged into the inverter's BMS port, using CAN. Fox ESS's manuals list the RJ45 pin-out for this link. On Fox ESS's ECS and EQ batteries the master module (the CM on the ECS, the EQ-M on the EQ) holds the battery's controller and talks to the inverter. The HV2600 has a separate BMS BOX instead of a master battery. The inverter uses this link to decide when to charge, when to discharge and when to shut down for protection. When the link breaks, the inverter cannot read the battery and the battery goes idle, with no charging or discharging, until communication returns. In the app this may look like the battery being offline.
For BMS Lost and Bms Ext Fault, Fox ESS's manual asks an installer to check the BMS cable is correctly and securely connected. A DIP switch in the wrong position, or a break between battery packs, comes under Bms Int Fault. Mismatched battery software raises its own alarms, and Fox ESS does not rank any of these causes. With your permission we review your Fox Cloud alarm history, battery data and firmware version. We get access when you share your login, or through an account transfer (£95).
Tell us the alarm name or code and what the app and the inverter's screen show. With your permission we review your Fox Cloud alarm history, battery data and firmware version. We then tell you the next step and who needs to do it. Independent from Fox ESS and your installer.
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