Im seriously struggling here. I want batrium to be awesome but it just isnt. It will be ok for awhile, but cell monitoring randomly drops out, or has “noise”. I have installed a system with the cellmat k9 thst seems to be pretty good. This system is a watchmon 4 with longmons and honestly its garbage. Constant tweeking and fiddleffing around. The longmons see a bunch of noise or something when the cells are almost fully charged. Then today randomly a bunch of longmons dropped out of comms. Amount and location of longmons constantly different. Ive replaced the little wiring harnesses and longmons themselves with no luck. The system keeps shutting off the inverters. Seriously about to rip it out and throw on a jk bms. This is ridiculous for the amount of money spent. I guess this is one last plea for help, i really want the batrium system to be great but it just isnt. I take care of another system that has similar issues. Ok rant over for now.
I run a watchmon 4 (almost 8 yrs now) with 140 longmons. In the early year I had trouble because I didn’t use proper twisted pair wiring from unit to the 1st longmon and from last back to the unit. My powerwall is large enough that the distance from 1st/last longmons to Watchmon are about a 20ft runs. The longmons use the standard (unaltered) cables to connect from one to another.
For the 20ft runs, I switched to cat5 (or cat6) twisted pair wire stripped out of an internet cable and my issues ‘mostly’ went away.
I still have occasional network freezes if the weather (humidity/temperature) drastically changes as my battery is under the house in a non-HVAC area exposed to vents to the outside. They’re not open to direct weather but it seems rapid/extreme storm/humidity changes can case one of the connections at a random longmon to stop working. This is easily visible as the lights (on the longmons) are on/frozen up to the one where the network is blocked. A quick wiggle of the connector and network resumes.
Not sure if any of this is helpful but I know what you mean by the frustrations. I’ve come to accept once or twice a year ‘toggle’ to keep it working and otherwise it really gives me piece of mind to display the toolkit (blue bar) monitor on my daily driver desktop to keep tabs on things.
Hi Ripvansparky,
I’m very sorry to hear you are struggling so much.
Have you emailed us at info@batrium.com yet about this particular issue? Have you provisioned your device so we can see data over time and maybe spot something?
Our LongMons are over 10 years old as a product, and we have come a long way with the K9. If you send us the serial number of the WatchMon we can guess the age of the LongMons.
Are all your cells consistently over 2V according to the LongMons?
Have you tried isolating out a few LongMons at a time to try and see if there is one that causes more problems than others
What XXXX is saying about climate and connections is true, and is exactly why we moved to larger connectors on the K9.
I get this but… if I may say… I REALLY APPRECIATE the longevity/support of the longmon network system - even with the potential of a small wart. The compatibility year after year with all the older ones / Watchmon from years past is very nice. This has allowed me to expand, year by year, bit by bit, my powerwall - with minimal BMS effort! This year I’m moving up from 140 longmons to 164 as I expand. It’s been fantastic and wanted to give a shout-out of job well done in this area from my perspective 
The downside of K9 from my perspective would be hundreds of wires (some many feet) and mounting the growing chain of units near the core. Whereas with longmons, it’s a single core ‘unit’ and it’s pretty easy to expand by connecting over to the next set of longmons at the physical powerwall - and then unplug/move/plug the 1 x long wire back to the Core. Here’s a pic to give the idea…
In any case, I mainly wanted to offer appreciation for the longmon system/support as it works for me very well - no to mention that my Batrium system is in year 8 heading to year 9 - good Watchmon longevity as well.
I hope the OP can provide more detail and perhaps get things working.
Why don’t you plan to place CellMates in the same way as LongMons? One longer wire to connect the Core and all CellMates and short wires from CellMates to cells. There is no need to place CellMates right next to the Core.
This picture shows, how I build boxes for cells:
The CellMate is located inside the box along with the cells. And then, there will be two RJ45 connectors on the box for using standard RJ45 cables for the CMU connections of the CellMates.