Really wish I could find the u27-36xpd for £90 each at the moment.
Valence XP Super Thread
- Thread starter Travis
- Start date
Yeah , I’ve just bought 6 more from eBay , had to pay more for those , £800 so £133 each which is still cheap given what they are capable of . The 6 I’ve just purchased actually originated from the same place but passed through a few peoples hands after so I’m glad the batteries are the same age and I think they’ll perform the same as my original 10 .
martinwinlow
New Member
- Joined
- Feb 6, 2021
- Messages
- 34
A bit late but no, their safe cutoff discharge voltage is 10.0V - so oodles of room... I would not have thought they are even half discaharged at 12.9V...
martinwinlow
New Member
- Joined
- Feb 6, 2021
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- 34
Forgive me but I do not want to read through this entire (enormous) thread but would be interested in a *cheap* ('ish) solution to the issue of monitoring a bunch of U27-12XPs all at once rather than having to do them one at a time via the Valence diagnostic app...
Anyone got any links to something, please?
MW
Anyone got any links to something, please?
MW
Cloroxbottle
New Member
I have a bank of three U27-12XP batteries wired in parallel.
I'm trying to set up a Mastervolt Powercombi-12-1200-50 inverter charger's settings to work with this bank.
The variables I can control are bulk charge voltage, bulk charge time, absorption charge voltage, absorption charge times, float charge voltage and equalization voltage, undervoltage protection, and overvoltage protection.
The undervoltage I've turned up to 12, decreased overvoltage to 15, and set equalization at 12.0 since I apparently can't turn it off.
I increased bulk voltage to 14.4, set absorption at 14.2, and set float at 13.6
Finally, the "times" are throwing me for a loop as I thought that these modes were dependent on depth of discharge. The defaults are 4 hours for bulk, 2 for absorption. Leave those alone? Change them? Divide battery capacity by the voltage selected for the modes and calculate bulk time to be 90% of that and absorption to be 10%? Not sure what to do about those two settings.
I'm trying to set up a Mastervolt Powercombi-12-1200-50 inverter charger's settings to work with this bank.
The variables I can control are bulk charge voltage, bulk charge time, absorption charge voltage, absorption charge times, float charge voltage and equalization voltage, undervoltage protection, and overvoltage protection.
The undervoltage I've turned up to 12, decreased overvoltage to 15, and set equalization at 12.0 since I apparently can't turn it off.
I increased bulk voltage to 14.4, set absorption at 14.2, and set float at 13.6
Finally, the "times" are throwing me for a loop as I thought that these modes were dependent on depth of discharge. The defaults are 4 hours for bulk, 2 for absorption. Leave those alone? Change them? Divide battery capacity by the voltage selected for the modes and calculate bulk time to be 90% of that and absorption to be 10%? Not sure what to do about those two settings.
Last edited:
Total newbie here so apologies for my ignorance. I am wondering if a Valence U27-12XP can be used as a house battery in an RV and charged off the alternator or shore power? Can it be used in series or parallel with a Pb-acid battery? I cannot get any help from Valence/Lithion and am not an engineer (or even close). I do NOT have a solar hookup. Also I don't have a controller and am not sure how complete the ones on eBay are. Any help appreciated? Experts please have mercy on a newb! @Travis
martinwinlow
New Member
- Joined
- Feb 6, 2021
- Messages
- 34
Hi David, A bit late in the day but:
1/ Do *not* use your U27-12XP in anyway with a lead-acid battery. Doing so will make it very difficult to protect either battery adequately from over/under charging.
2/ Yes you can use the U27-12XP as a 'house' battery but I'd say one module is not enough for any realistic use unless you are *purely* powering LED lighting from it (mobile phone charging, too) and not very much at that.
Essentially you must simply (but very effectively) protect the U27-12XP from being discharged lower than 10V and from being charged to more than ~14V. There is a lot of talk about the need for balancing etc but, in my experience, as long as you avoid (like the plague) the extremes of SOC, these batteries are nigh-on bulletproof. The same cannot be said of any other Li battery chemistry than basic LiFePO4 - as these modules are.
Therefore, any run-of-the-mill 12V charger *can* work but just be sure that it does not take the module higher than 14V - and most designed for lead-acid almost certainly will on their own. You could combine one with an additional circuit to cut power to the charge when it gets to 14V - plenty of kit out there to do that. But I'd be inclined to add at least some level of redundancy to that as well as an alarm should that system fail and the charging voltage rise higher than 14V (or whatever V you choose).
Likewise from an over *dis*-charging POV something like the Victron 'Battery Protect' would be useful but again, I'd be looking for at least a second layer of protection and, again, an over-discharge alarm.
meganet
New Member
Hello,
I have a few U27-24XP and not able to read them with the 12.12 software. It is a different one? Wonder because the software only shows up to 6s and the 24v are 8s modules. The BMS on them are different than the 12v model pictures.
Thanks
I have a few U27-24XP and not able to read them with the 12.12 software. It is a different one? Wonder because the software only shows up to 6s and the 24v are 8s modules. The BMS on them are different than the 12v model pictures.
Thanks
Loanrangie
New Member
Hi all, are these valence batteries worth getting in 2025. Found some locally on Gumtree for $110 each but information is pretty scarce online apart from here and a few youtube videos.
I would like 2 to replace the 2x100ah AGM's in my caravan that i have fitted a 400w solar system to, watched a video on making the USB cable for software management which i'm more than cable of but wondering if its completely necessary ?
I would like 2 to replace the 2x100ah AGM's in my caravan that i have fitted a 400w solar system to, watched a video on making the USB cable for software management which i'm more than cable of but wondering if its completely necessary ?
My understanding is the software is needed to activate the onboard BMS for cell balancing. It is also a great way to get info on the batteries. I run a windows tablet to save space and power in my van.
Question has anyone been able to connect the software to a Bluetooth RS485 adapter? I am trying to connect using a
DSD TECH SH-B20 RS485 to Bluetooth SPP Adapter Support Android and Windows OS
When I pair to the device it creates 2 virtual comports but the software can not connect to either one. I get a error pop up.
alexandertgtalbot
New Member
Short answer: No.
Long answer: It may well be related to an issue I myself experienced recently. The UART controller, i.e. the hardware/device itself, could be disregarding frame setting of 8N2 and forcing 8N1. 8N2 is a hard requirement for communicating with the BMS. Think of it as requiring all written language sentences to have two full stops (periods) instead of just one.
rortiz1984
New Member
Hello meganet. Did you ever figure it out? Does it need a different software?
alexandertgtalbot
New Member
@rortiz1984 - Have you got the same problem?
Hi, I have the same problem with the U27-36XP. with the valence_diag12_12 I can only see the IDs and change them, but when reading it tells me "check the port or ID". by monitoring the COM-Port I see that there are STATUS_TIMEOUT during the information request function, but none during the ID change function
alexandertgtalbot
New Member
Happy to share an app I'm using to monitor my batteries if you'd like a quick test. If you're like me you just want to know that the batteries are working. It is a work in progress that I've only validated against my u27-12xp v2 units but in theory it should read the data all the same.
I managed to bring the U-BMS CAN Bus data into HomeAssistant via ESPHome using an ESP32 DEVKIT and a cheap CAN BUS Hat.
h/t to the folks who decoded the CANBUS for a U-BMS to Victron setup here: https://github.com/gimx/dbus_ubms -- I have a copy of the protocol laying around, so I expanded what they put into their setup to add more sensors/variables:
Can find the YAML for that on my github -- this is really just proof of concept currently, but I expect to clean it up in the days to come.
github.com
You'll need a working U-BMS for this to work.
Here's the CANBUS hat that I know works - I used a standard ESP32-DEVKIT1 with this:
I think I'm going to use this Waveshare unit as it's really nicely packaged for a DIN rail and has all sorts of isolation, etc. and it isn't that expensive:
I'm using this along with some z-wave switches to do some load shifting for my Homelab -- works really well and let's me shift my server load during 5-9PM from 45c/kwh to 9c/kwh. Savings isn't huge - but it was a fun project nonetheless :-D
I'm pretty swamped right now -- but if there is interest, I can try to get AI to write a how-to for me once I move this past proof of concept.
h/t to the folks who decoded the CANBUS for a U-BMS to Victron setup here: https://github.com/gimx/dbus_ubms -- I have a copy of the protocol laying around, so I expanded what they put into their setup to add more sensors/variables:
Can find the YAML for that on my github -- this is really just proof of concept currently, but I expect to clean it up in the days to come.
tasty_haos/esphome/valence-ubms-canbus at main · derekwolfson/tasty_haos
Stuff for my personal instance of HAOS that I'd like to share. - derekwolfson/tasty_haos
github.com
You'll need a working U-BMS for this to work.
Here's the CANBUS hat that I know works - I used a standard ESP32-DEVKIT1 with this:
Amazon.com: XICOOLEE CAN HAT SN65HVD230 can-Bus transceiver Module Stably Long-Distance Communication Functions Communication Module Single Channel : Electronics
Buy XICOOLEE CAN HAT SN65HVD230 can-Bus transceiver Module Stably Long-Distance Communication Functions Communication Module Single Channel: Network Transceivers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
amzn.to
I think I'm going to use this Waveshare unit as it's really nicely packaged for a DIN rail and has all sorts of isolation, etc. and it isn't that expensive:
Amazon.com: Industrial ESP32-S3 Control Board with RS485 and CAN Communication Interfaces, Supports Wi-Fi /Bluetooth, Better for RS485 Modbus Modules or CAN Devices, Built-in Protection Circuits, Safe & Stable : Electronics
Amazon.com: Industrial ESP32-S3 Control Board with RS485 and CAN Communication Interfaces, Supports Wi-Fi /Bluetooth, Better for RS485 Modbus Modules or CAN Devices, Built-in Protection Circuits, Safe & Stable : Electronics
amzn.to
I'm using this along with some z-wave switches to do some load shifting for my Homelab -- works really well and let's me shift my server load during 5-9PM from 45c/kwh to 9c/kwh. Savings isn't huge - but it was a fun project nonetheless :-D
I'm pretty swamped right now -- but if there is interest, I can try to get AI to write a how-to for me once I move this past proof of concept.
Great work, guys; I really appreciate the effort you put into this thread!
I need your help in two areas:
1) Battery safety
2) Battery management
1) Battery Safety
Currently, the eight batteries are set up in 2S4P, as I said, and all eight of them have a 300A MRBF installed on the positive terminal. My thinking was that an MRBF is so-so for 24V, but if all of them have a fuse, then basically it is a 12V system at the per battery level. (Please correct me if I am wrong here). All of the series strings have the same length of positive and negative cables and are connected to a common busbar. The cables are appropriately sized (50sq mm, 1/0 AWG), and all strings have a 300A T-Class fuse before the busbar.
Is this acceptable?
2) Battery Management
Now, this part is definitely not acceptable, but anyway, I am here for help. The batteries run without a BMS as I could not get the U-BMS running. Yes, I know. The system has only been up for two months, not fully "in production", only kind of, and I lowered the charging voltage for the bulk charge when it's on shore power, and I only charge it to 90% and monitor the batteries through the diagnostic software.
As this is the Valence thread, I don't need to explain how hard it is to get the U-BMS working. I have the config software, but I haven't got the CAN bus running. (** Help needed — is there any working alternative to Lawicel CANUSB? **) Even if I could get the CAN bus running, I am not sure that I could config my own 2S4P as there is a very slim chance that the BMS is configured that way. So, ideally, this would be the preferred path if it is achievable.
Alternatively, I am happy to crack them open, get the balance leads out, and have two external BMSs configured. (** Help needed — my understanding is that I can use one BMS for every two strings in series? **) It would be nice to use an ESP32 for the task so it could report to Home Assistant Operating System (HAOS) as some of our fellow member has already done, but then I need to balance the series string separately. But integrating with Home Assistant is definitely preferable, even with a third-party BMS like JK, if possible.
So, that's it. Send me to hell.
Back story for the ones interested
I originally bought six U27-X12 batteries back in 2020, and they sat for three years in a cupboard. Actually, I remember using the diagnostic software to select these six out of more than 30, based on the on-board statistics. They had no errors and charging cycles ranging from 6 to 17, so practically new old stock, given they were made in 2012 :D
Anyway, after three years of neglect (apart from the occasional check of their SoC), I finally got my Victron gear and hacked the system together for a test run at a friend's house. Big mistake, as when they were renovating the shed they left them outside in the rain and two were gone, meaning completely_full_of_water dead. Great. I bought another four last year at a third of the 2020 price, so I have eight now. Somewhere along the line, I also bought a U-BMS-LV.
Comes second part of 2025 and my would-be camper is ready for the install. All eight of them go at the back with the whole Victron gear. The system is running on 24V in a 2S4P configuration. I know, that's my first mistake. Actually, second, the first was spending £2k on the original six batteries in 2020. For that kind of money, I could now buy 24V batteries with a built-in BMS. Anyway, on the roof, there is 630W of solar, which confidently produces 300–600W per day here in the sunny UK during the winter. The system has an MPPT, two Orions for generator charging, a 3kVA MultiPlus II, a 500A shunt, and a Cerbo GX, and it's integrated into Home Assistant. Please see the layout, which is a screenshot of the SVG file I made back then.
Thanks!
Apologies for the Norsk batteries - at least I made the effort to find one with the same colour. The rest of the stuff is for running the van, server with proxmox (HAOS, traccar, mosquitto, etc), Minix for the tele, and a hacked OBIHAi for the landline. Yes, in the van.
I need your help in two areas:
1) Battery safety
2) Battery management
1) Battery Safety
Currently, the eight batteries are set up in 2S4P, as I said, and all eight of them have a 300A MRBF installed on the positive terminal. My thinking was that an MRBF is so-so for 24V, but if all of them have a fuse, then basically it is a 12V system at the per battery level. (Please correct me if I am wrong here). All of the series strings have the same length of positive and negative cables and are connected to a common busbar. The cables are appropriately sized (50sq mm, 1/0 AWG), and all strings have a 300A T-Class fuse before the busbar.
Is this acceptable?
2) Battery Management
Now, this part is definitely not acceptable, but anyway, I am here for help. The batteries run without a BMS as I could not get the U-BMS running. Yes, I know. The system has only been up for two months, not fully "in production", only kind of, and I lowered the charging voltage for the bulk charge when it's on shore power, and I only charge it to 90% and monitor the batteries through the diagnostic software.
As this is the Valence thread, I don't need to explain how hard it is to get the U-BMS working. I have the config software, but I haven't got the CAN bus running. (** Help needed — is there any working alternative to Lawicel CANUSB? **) Even if I could get the CAN bus running, I am not sure that I could config my own 2S4P as there is a very slim chance that the BMS is configured that way. So, ideally, this would be the preferred path if it is achievable.
Alternatively, I am happy to crack them open, get the balance leads out, and have two external BMSs configured. (** Help needed — my understanding is that I can use one BMS for every two strings in series? **) It would be nice to use an ESP32 for the task so it could report to Home Assistant Operating System (HAOS) as some of our fellow member has already done, but then I need to balance the series string separately. But integrating with Home Assistant is definitely preferable, even with a third-party BMS like JK, if possible.
So, that's it. Send me to hell.
Back story for the ones interested
I originally bought six U27-X12 batteries back in 2020, and they sat for three years in a cupboard. Actually, I remember using the diagnostic software to select these six out of more than 30, based on the on-board statistics. They had no errors and charging cycles ranging from 6 to 17, so practically new old stock, given they were made in 2012 :D
Anyway, after three years of neglect (apart from the occasional check of their SoC), I finally got my Victron gear and hacked the system together for a test run at a friend's house. Big mistake, as when they were renovating the shed they left them outside in the rain and two were gone, meaning completely_full_of_water dead. Great. I bought another four last year at a third of the 2020 price, so I have eight now. Somewhere along the line, I also bought a U-BMS-LV.
Comes second part of 2025 and my would-be camper is ready for the install. All eight of them go at the back with the whole Victron gear. The system is running on 24V in a 2S4P configuration. I know, that's my first mistake. Actually, second, the first was spending £2k on the original six batteries in 2020. For that kind of money, I could now buy 24V batteries with a built-in BMS. Anyway, on the roof, there is 630W of solar, which confidently produces 300–600W per day here in the sunny UK during the winter. The system has an MPPT, two Orions for generator charging, a 3kVA MultiPlus II, a 500A shunt, and a Cerbo GX, and it's integrated into Home Assistant. Please see the layout, which is a screenshot of the SVG file I made back then.
Thanks!
Apologies for the Norsk batteries - at least I made the effort to find one with the same colour. The rest of the stuff is for running the van, server with proxmox (HAOS, traccar, mosquitto, etc), Minix for the tele, and a hacked OBIHAi for the landline. Yes, in the van.
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