Hello!
Do you have experience with the REC-BMS SI in a Victron-based setup? I believe it should work well with the Cerbo GX over Canbus, and that I could use the REC-BMS LCD in addition to the CerboGX to view individual cell voltages and such.
Do you know the difference between the Q and the SI? I have tried contacting REC directly but they referred me to the USA office, which referred me back to the Slovenia one and while I wait for them to figure it out the project is getting delayed...
Additionally, which temperature probe should I order for this BMS?
Thank you!
Hi, I moved this to our forum as it may be of interest to others.
The SI is basically a Q Series with custom CANBus integration code for a specific vendors charger and/or inverter such as Victron or Sunny. This will allow the REC BMS to \"soft\" disable your inverter and charger before initiating a hard relay trip. In addition it has some cool PV logarithms. See the manual snippet below.
For our systems, our Q Series actually includes an interface for both the Wakespeed WS500 Smart Alternator regulator and Victron as this is the most common configuration for marine applications, and this is the unit that is stocked in the US.
And for the LCD, yes both your CANBus and RS-485 networks are available so you can use both networks and a special crossover cable for the VE Bus/ CANBus network is available.
The battery temperature is a Dallas Semiconductor unit and here is the link for your reference
https://www.offgridsoftwaresolutions.com/product/rec-q-bms-temp-sensor/
I have also pulled together a parts list and pre-filled a cart for your review. Feel free to delete items you may already have.
A couple of notes to consider:
I have arbitrarily added 2 temperature sensors. Depending on your pack size you may want more or less (up to 3)
Depending on your system voltage you may want to select the 48V isolation contactor
The new WiFi adapter will be available in April, and will replace the functionality of the Windows Software
And if you re-enter your order online by adding components to your REC BMS as part of a kit, you will save 5% on those components (but I can\'t save that parameter in the cart link)
https://www.offgridsoftwaresolutions.com/cart/?fill_cart=8986,9009,9015,9055,9069,1761,2x9066
Hope this helps!
To follow up on this, for a mobile (Van/RV) installation that has a 16 cell LiFePo4 pack, Victron Multiplus 3000, SmartSolar MPPT 100/30 and CerboGX, would you recommend the Q or the SI?
Thank you!
For your installation we would suggest the Q Series, as it includes both communications for the Victron as well as the WS500, should you ever want to look at upgrading or adding a second alternator
Thank you. Unfortunately my battery pack is 24v and my alternators are 12v (the van comes with two alternators and I cannot replace them or add a third one) so I am not sure the WS500 would be possible. Other than the support for the WS500, are there any other differences?
Thats fine, its why I mentioned adding a second alternator, possibly in the future. Often you leave your factory alt. to maintain your cranking batteries but if you have a good sized LFP bank you want to charge fast, or to help run a large load, like AirCon, you find a bracket and pulleys and add a second alternator in whatever voltage your house bank is. By using the Q series, you leave that option open for future integration of your charging system
Good luck with your install.
Unfortunately that won\'t be possible for me since my van already comes with two alternators from the factory, and they are both 12v and interlinked together (it\'s a 2021 Ford Transit). So I am stuck with two 12v alternators while my battery pack is 24v.
But putting aside the support for WS500, what other differences are there between the Q and the SI?
Thank you for the quick replies!
Same unit, different firmware! And we stock the Q series, whereas we would need to send you the SI firmware to be installed using the PC software app, if you wanted the SI unit.
Does the Q series unit you have also have the \"\"soft\" disable your inverter and charger before initiating a hard relay trip. In addition it has some cool PV logarithms.\" that you mentioned above?
Would it be possible to update the firmware using the upcoming WiFi adapter? Or would I need to buy the PC software in addition to the WiFi adapter?
