I have 3 * 24/3000/70 Multiplus , 3 * 250/100 MPPT controllers and 6 * 220ah gel batteries in a 4 sq meter room.
The room currently is at 25 degrees on a cool day and up to 40 degrees on a Hot day. Here is South Africa we have alot of hot days,
Hi 12VMan (and Victron staff please). I found your thread on Lithium battery protect settings while searching, but decided my comment should be a new question.
Thanks for your answer in that thread, mentioning that Victron lithium batteries issue a temperature alert at 5C. This gets my attention. My research to date was indicating that lithium batteries are OK for charging down to around 1C (and for discharging well below 0C, as an aside). I need to pursue this, as I'm planning to use Victron LiFePO4 batteries in Arctic conditions, in an expedition yacht that will be static for days to a week or two. Water temps will be down to around 2-3C, sometimes lower depending on icing. I'm looking into the need for heating for the battery box, which will be under the insulated floorboards and so outside of the primary heated spaces. If 5C is the real deal, I need to get serious with calculations on battery energy that might be consumed in making the batteries warm enough to be chargeable. Or other heating.
So, where is this 5C figure coming from? OK, I see +5C mentioned in the 12.8V LiFePO4 battery data sheet.
This prompts a few specific and important questions, about the Victron 12.8V 300Ah variants:
1. What is the lower internal battery temperature at which the battery signals to a connected BMS that charging is not permitted?
2. If the answer to Q1 is different than +5C, what is the consequence in terms of battery health (and charging efficiency?) of charging occurring between the two temperatures?
3. Does the answer to Q2 depend on the rate of charging?
4. If the internal battery temperature is just high enough for the battery to allow itself to be charged, and in this case at a low rate of 20A per battery (80A from a normal alternator, shared between 4 batteries), will this charging slowly warm the batteries up such that a higher rate of charging can be initiated in due course?
5. At what battery temperature (measured by a sensor on the positive terminal, or is there a way to get the internal temperature?) can high rate charging at ~150A per battery be initiated, such that no appreciable damage to battery health occurs? Would it be prudent to step the charging rate up slowly as the batteries warm up?
Clearly, it will be helpful if I rig a temperature sensor for the battery box, to guide appropriate action before each charging session.
The boat will use an Integrel On-Engine Charger (basically a big and very efficient second alternator) which can charge at up to a very high rate. Or it can be turned off so that charging is via the engine's standard alternator only. I might need to raise the battery box temperature before starting to charge each week or so. Heat from the main engine during these charging events will then help.
Thank you for your help with these questions. :-)
My Orion Tr Smart 12/12-30 Charger runs hot, and the output current folds back considerably. Anyone else with this problem? When cold, it will output 33A. When hot, it will fold back to 26A or less. Parts of the case may exceed 134dg F, in a cool (60dg F) environment. By adding a 80CFM fan above the fins, the case temperature is lowered by 20 degrees F, and the unit will continuosly output 30A. It would appear that the heat sink is undersized. Comments?
The first time I started this Quattro 48/8000 it showed a temperature alarm and wouldn't start inverting. After a few minutes the alarm cleared spontaneously and I assumed that it was just a fluke. Now it is re-occurring randomly, usually when Quattro is in passthru mode and not at all hot. Another post mentioned that sometimes the cable to the temperature sensor could become detached in shipping. I have located those connectors and they are attached. Disconnecting them will produce the fault when everything is functioning. The fault seems to last anywhere from 20 seconds to hours. I cannot use the Quattro, even in passthru, during that time. It's part of a three phase system, no issues with the other phases. Not overloaded or really hot, running about 34C now but has gone up to 46C with no problems. Battery temperature sense is not connected. Fans are running at high speed on the affected inverter. Temperature light blinks on startup and then goes solid.
Can anyone give details about the internal temperature sensors on the Quattro? How to test? A new inverter is several weeks away if we have to go that route. The dealer is involved but hasn't seen this error before. Would prefer to be able to replace parts as I have a way to get small parts in the next week or so if I know what to order.
I used to be able to see the battery temperature on the main Dashboard. I recently made a few changes to my setup and now the temperature has disappeared. The changes made were:
1) Removed BMV-702 and installed SmartShunt
2) Installed a BMS and connected to the VenusGX via CanBus
3) Updated MultiPlus firmware to latest and enabled ESS
The MultiPlus, SmartShunt, and BMS each have a sensor and are reporting temperature. I can see it in the Remote Console and on VRM if I configure an Advanced Widget, but I can't seem to make it show on the Dashboard. Appreciate any advice, thank you!
Does anyone know the minimum temperature of the GlobalLink 520?
I recently changed out my CerboGX (temperature limit -20 C) with the GlobalLink 520. Using device with SmartSolar 100/30 MPPT (temperature limit -30 C) and SmartShunt (temperature limit -40 C). I will find out this winter whether or not this unit will work all winter in my unheated Alaska location.
The extremely low power consumption (measured at 10 mA) of this setup should survive the winter with flooded lead-acid batteries. With the CerboGX, I had to shut down the loads including CerboGX during -30 C temperature conditions.
Global warming has helped since it has been over 10 years since I have seen -40 C at my location.
Old setup for previous years used industrial rated (-40 C) components for all parts of the system; however, power consumption required me to limit operation to sunny days only.
We have a 24V DC Quattro 110-120V AC Inverter/Charger and want to be able to shut off charging from the Quattro to the non-Victron lithium batteries when the temperature drops below a certain point. The system also has a CerboGX and BMV-712 wired in. The Quattro temperature sensor is connected to the 24V battery pack and we have a second temperate sensor we can connect from the BMV-712 smart shunt to the batteries if needed.
Currently the Quattro only measures high battery temperatures as we under stand it. Is there a way to get the relay in the Quattro to disconnect Quattro battery charging if the temperature drops below a certain point?
Thank you for your help with this.
I have a 250/100 SmartSolar MPPT.
This is operated at max. 216V and max. 27A. The PV modules have 5kWp.
Ambient temperature is about 23°C
How hot is it allowed to become, at 5000W continuous power?
Connected is a 48V system.
With a temperature sensor enclosed with the Cebro, I measured approx. 51°C at 4000W.
This has been corrected in advance to 23°C room temperature (offset in software = -6°C).
Measurement of the temperature: Centered on the front of the case
Temperature sensor is mounted with 3M 8926 heat conductive adhesive tape.
Cooling of the MPPT = Passive, no forced convection by fan.
Thanks a lot!
I just added on a couple temp senders to the Cerbo unit and have it reporting on VRM. I have other data from the Cerbo reporting on my NMEA 2000 network such as inverter power, battery voltages and such. I have not been able to see the temp sensors on my N2k network. In the cerbo device menu the temp sensor shows it has an instance number assigned of 25 but from my maretron screen there is no temp data available other than known other devices. Any one else been able to get this to work?
Does anyone know where is the best (read: hottest) place on the outside of this thing to place a temperature probe? My mounting situation is not ideal and I'm providing some external fans for airflow, that will be controlled by said probe. Do not want them cranked at 100% all the time, especially since it seems the Multiplus itself doesn't even want/need to run it's own fan at all most of the time (when I'm using 2, 300W or so). Silence is golden. I suspect there's a spot that gets hottest when charging the battery and another spot that gets hottest when inverting heavily... I'm on a 15A shore hookup right now (Just installed it a couple days ago) though so I can't run the charger full-tilt to see where the charger heat is, and I don't really have any _full_ loads to put on the inverter (I guess I could turn on the A/C and plug in a space heater and let them battle for a little while... but hoping somebody's got a good answer first)
I'm currently building an RV off-grid system based around a Lithium Tesla Battery and MultiPlus. In the system is also a BMV 702, BatteryProtect 220 and Color Control.
As the Lithium Battery really doesn't like to be charged below freezing temperature I'm planning to have an automated heating pad that keeps the battery warm, but I would like to have a fail safe which disables the MultiPlus Charger whenever the temperature of the Battery reaches 5°C
My current setup is to connect the BMV-702 Temperature Control Sensor to the Battery and then connected the BMV-702 Relay to the MultiPlus AUX1 which controls the Charger via the Charge Assistant. This works nicely, but I was wondering:
1. The MultiPlus already has a Temperature Sense Connector plus the Temperature Sensor shipped, when I measure the voltage of the Temperature sensor I get a reading of 2.6V at 25°C. Is there any datasheet of the Temperature Sensor that I could use to configure the MultiPlus Assistant for temperature? I would really like to not depend on the BMV for the temperature measuring and best have the MultiPlus measure the temperature directly.
2. I found the new Shared Temperature Sense feature of the Venus/ColorControl: https://www.victronenergy.com/blog/2018/10/17/venus-os-v2-20-scheduled-charging-equalize-and-more/ which mentions:
the Venus-device will send the battery temperature to the connected Solar Chargers and Inverter/chargers.
But I don't see anything in the MultiPlus Configuration Screen to do anything with that Temperature or any other way that it actually receives the temperature form the Venus/ColorControl.
Plus just two other small questions:
1. Is there any way to see the current voltage reading on the MultiPlus AUX inputs? I'm having a bit a hard time to find the correct voltages to use in the Assistant
2. When I disable the Charger in the VEConfig all together, but then enable the Charger again via the Assistant based on the AUX1. The charger is actually running! That's a bit scary ;) Also which charge settings are used? I assume just the last settings of the charger before it was disabled all together?
@mvader (Victron Energy) said the following about the temperature derating of the 100/30 MPPT:
"Its a linear derating from full power at 40 degr C to zero at 70 degr C"
Is it really as simple as that, or is there some dependency on the operating point?.
I have tested two different systems, one of them shows very clear derating with temperature and the other shows no observed derating at all.
System #1 960W, Vmp:33.6V, Imp:28.9A, MPPT:150/35
System #2 720W, Vmp:43.6V, Imp:16.5A, MPPT:100/30
When operating in good sun with the controllers kept under 40 degreesC by forced cooling then System #1 delivers in excess of 900W and System #2 delivers around 650W.
When the MPPT temperatures (at the heatsink) are allowed to rise to 50 degC, System #1 output derates by almost 300W whereas System #2 does not derate at all. There is no change in the temp of the panels, only the MPPT, and in both cases the LiFeSO4 batteries are accepting ALL of the power that can be delivered to them.
Why do these two systems behave so differently if the MPPT derating is a simple linear 3.3% per deg above 40 degrees?
I see from the 250/100 datasheet:
Operating temperature -30 to +60 °C (full rated output up to 40 °C)
In our summer conditions, almost all MPPTs we have installed are too hot to touch.
We are collecting thermal imaging to provide examples, but in some cases, we have installed forced cooling in order to satisfy customer concerns.
We are concerned that this may result in a higher failure rate than Victron intends and we note that there is no warning between Venus OS and MPPTs about temperature. We have never observed an MPPT derating on over-temperature, which we would expect to see at temperatures over 40 degrees C per the datasheet entry above.
I'm sure places like Australia and the Southern US where Victron is also popular will also be experiencing the same sort of operating temperatures.
We have designed and are testing a robust, temperature driven forced cooling solution for our installations going forward but it comes at a cost and we need to determine whether this is actually necessary from Victron's perspective.
Any input or advice on this would be appreciated.
Persistent high temp alarm although all seems within limits. would appreciate suggestions of investigation/cause.
Hi all. My Multiplus-II (24/3000/70-32, fw v.487) is acting strangely today. Been fine-tuning my setup since august last year and everything have been working perfectly. I am using Venus OS large with node-red to control most functions of the setup, which includes two shunts (one to measure battery current and one to measure PV current), several off-brand MPPT's, and a big battery bank of 32 x 75Ah AGM batteries.
Today i received a warning e-mail from my node-red system about a temp warning. I went to the unit and checked, it was warm, very sunny day which means several dump loads have been running very long with a total of 2 kW, not surprising that it got hot, but after removing the lower grill to ease air flow the warning went away. My idea was next to help it a bit by enabling the grid and power assist on 3.5 A to take some of the load off the inverter for a while. I have used power assist very much and it has always kept the limit, but to my surprise, even though I double checked the setting in the console, when I stopped ignoring AC in, it went up to 8 A power assisting, then switched to passthru not inverting at all, then back to power assisting 7-8 A and to passthru and flipping between the two constantly. Wut?!, I ignored AC in which had it inverting the whole load perfectly fine.
In the evening when one dump load had turned off and the load became lower (around 1500W), I tested the power assist function again. It is set at 3.5A still and it started assisting with 8A, then after a few seconds started going down and finally settled at the level I am used to seeing. Now it goes to the "right" limit straight away when stopping ignoring AC in, working as it has always been before.
Anybody have an idea what caused this? I merely want to understand it, I believe it is a good idea to install an extra fan to cope with these cloud-free sunny days, but why the power assist function would become non-functional because of a bit of extra heat is beyond me. Note that it never went into temp alarm, only temp warning...