SBMS0 connection to Victron Battery Protect

[Dustin Dudley]

Off the top of your head, does anyone happpen to know which port on a Victron Battery Protect should be connected to EXT I03 set as type 2?

[Dacian Todea (electrodacus)]

You just remove that short black wire link from the 2 pin connector and connect the two EXT IO3 pins there.

[Dustin Dudley]

Thank you. One more novice question for you. I have 2 shunts (for PV and Battery Current). They are Riedon RSA 125Amp / 50mV shunts. I am using it on a 12v battery consisting of 4 280Ah Lifepo4 cells in series. I am using an SBMS0 BMS. I am trying to calculate the appropriate value for configuring the SBMS0 but I am second guessing myself. Would I set the PV shunt and Battery shunt values to 0.4?

[Dacian Todea (electrodacus)]

Yes you are correct 50mV / 125A = 0.4mOhms so you will set 0.4000mOhm in SBMS0 for both the battery and PV shunt.

But it is strange that you have a 125A version. I do not see that option in their catalog https://riedon.com/media/pdf/RS.pdf Maybe you have the 150A then it will be 0.3333mOhm

[Dustin Dudley]

I am less certain now. Here is a picture of the order. It says "RSA - 10 to 150 Amp DC Ammeter Shunt", but then below that in grey it says "125 Amp / 50 mV" and I don't know if that means it is 125A or 150A.

[Dacian Todea (electrodacus)]

It is likely not from Riedon but should be just as good (maybe even made in the same factory). You will need to see what the marking in it say and set the shunt resistance value based on that.
When I make a search for 125A 50mV RSA shunt I find this https://www.alibaba.com/product-detail/CG-FL-15-USA-Shunt-Resistor_62218507966.html  so it is possibly this witch will be fine.

[sailingharry]

Dacian has given you the "book answer."  My configuration is a bit more complex, so I know far more than I have any desire to know....LOL

There are two terminals in that 2-pin connector.  You can short them together (as Dacian has said, and as the jumper wire says).  Or, you can short the "L" to ground or short the "positive" to power.  These are both approved in the manual.  This means that you only need to send one wire to the BP,  the other can go to power/ground (depending on your configuration) at the SBMS0.

Also, if you wish to concurrently control a MultiPlus inverter/charger, it gets very complex (you can do an inverter AND a BP using two IOx, but that uses up IOx pretty fast...).  The inverter, in "2-signal BMS" mode, can use the temp and aux 1 for discharge (temp) and charge (aux 1) (note, I could have them backwards...).  These are active by taking the "+" terminal to ground (you can't take the positive terminal high, it doesn't do anything, and the "-" terminal is a direct connection to ground so it is useless).   So, you can control a BP and a MP with a single IOx -- you connect the MP "+" and the BP "L" terminal together and take both to one IOx.  The other half of the IOx goes to ground.  Note that the "default" MP configuration for charge and discharge (I forget which is which) won't work, but if you reverse them (temp and aux1), then it works perfectly.

Another small detail.  I have a switch in my ATC (allow to charge) wire, which allows me to force-disable all charge sources to let the battery run down.  For indication, I have an LED, one side to DC+, the other (through a 1k resistor) to the switch on the BP/MP side.  I also have a switch that enables/disables the inverter, wired similarly (on a boat, the inverter is used under an hour a day).  When the switch is closed (and the SBMS0 is allowing charge), the LED glows.  A small detail I had to figure out -- the LED would send power through the MP "+" terminal (which is really at 5V, not 12V) and glow.  So I had to add a diode that allows the MP "+" to go to ground, but didn't allow the diode to backfeed.

One last detail on the BP. If you have a bluetooth voltage source (I have a Smart Dongle) in the system, it MUST be on the solar panel side of the BP.  If you put it direct on the battery, the solar panels will put out 16-17V and the BP will erroneously report "E1 -- Short Circuit."

Far more than you asked for.  But maybe helpful at some point.

Oh crap... you are talking about Type 2, not Type 1.  Much of my commentary works for that use, too.   But it really was targeting using a BP for Type 1 control.

[Dustin Dudley]

Dacian has been very generous with his time and I appreciate it. Thank you also to sailingharry. Another newbie question for the group. I live in a very windy climate. Does anyone have any experience with something like this: https://a.co/d/d9oBTXU and, if so, can anyone tell me if (and if so, how) this can be wired into the 12v battery system described at the beginning of this thread?

[Dustin Dudley]

I am building a 12v battery using 4 Eve Lifepo4 3.2v, 280 ah cells connected in series. (This is a stand alone system for my gate controller and wifi repeater at the entrance to my land). I have an SBMS0 and a DSSR20 and a Victron 12v inverter. I "think" I have learned that the only way to use the DSSR20 instead of a solar charge controller is if the panel voltage matches the battery voltage. Is this correct? I also have a Victron BattreryProtect 100amp to wire in, as well as some thermisters to try to incorporate to prevent sub-freezing charging.

[sailingharry]

You will need to dig into the manual to get information.  I looked online, and couldn't find a copy of the manual, so I can't help there.  However, I have some thoughts.

First, prepare yourself to be very disappointed.  On our boat, we had a D400, a high end marine unit with similar specs (and a VERY different price...LOL).  Rarely did it put out 50W, let alone 400W.  In winds less than 15kts (mph), it doesn't do much.  On a sailboat, the "damage" done to solar production (space is very limited, and shade is a challenge) wasn't worth the limited output of the wind generator.  But land is a different story, indeed.

As far as connecting it.  On the D400, there was a "brake" that would switch in a big resistor across the output, which would stop the spinning.  This could be implemented with fairly robust relay driven by the Type 1 IOx.  You may well need to have a relay driving a relay, to get the IOx current low enough.

The listing says it has "open circuit protection."  I'm not sure what that means, but if (repeat, IF) it means the output of the controller (the two wire, 12V, 30A wires) can be randomly disconnected and reconnected, then you could send the output to a Battery Protect 220A device, and the Type 1 IOx could open/close the output.  But rotating machinery tends to not like that behavior at all (huge voltage spikes, etc) and I have no idea how this unit would react to that.  It would not be a complete surprise if the first time you opened it you fried the controller and the Battery Protect as well.

If you can get a copy of the manual, and send me the manual or a link, I can maybe help some more.

Harry

[Dacian Todea (electrodacus)]

Dustin,

I have installed a very similar wind turbine about 10 years ago and it was running for maybe a year before I disconnect the wires and used them for extra solar panels. And this is also a windy place is just not windy when you will really need it.

https://www.youtube.com/watch?v=kR7hS58U17E  It was maybe a bit more advanced as it had extra mechanical protection to strong winds (the tail will rotate out of the wind in very strong winds).

It was also correctly rated 300W and that is at a rated wind speed of 12.5m/s (45km/h) (28mph) and this will need to be clean non turbulent and constant wind speed witch is very unlikely just a few meters out of the ground. The wind tower costs way more than the wind turbine and so are the cables that need to be short and thick way more than what you will use for solar PV panels of same rating. I reused those cables from that single wind turbine for 9x 260W solar modules.

At low wind speeds you produce nothing (not like solar panels in a cloudy day but absolutely nothing).

The equation for wind power is P = 0.5 * air density * swept area * wind speed^3 * efficiency

According to spec your wind turbine is slightly larger diameter than mine 1.3m vs 1.14m  so mine had a swept area of 1.02m^2 and the one you linked to should be 1.32m^2

For mine P = 0.5 * 1.2 * 1.02 * 12.5^3 * 0.25 = 299W (I assumed 25% efficiency)

The one you linked to P = 0.5 * 1.2 * 1.3 * 12.5^3 * 0.25 = 381W (same assumed 25% efficiency).

Now see what happens if wind speed decreases to half so from 12.5m/s to 6.25m/s

P = 0.5 * 1.2 * 1.3 * 6.25^3 * 0.25 = 47.6W  (for half the wind speed you get 8x lower output power is not like with the sun where half the solar illumination means half the power). And 6.25m/s is 14mph

So my advice is do not bother with solar just add extra few PV panels for the cost and they will produce way more and also last much longer. 

Also the electromagnetic brake is complicated as you can not just short the wind turbine output while it spins as that will damage the blades (they will brake off and fly as projectiles) In my wind controller that was done by applying a PWM with increased duty cycle until the blades stopped (so a gradual electromagnetic brake ). Not sure what that included controller is doing but it can not just relay on a dump resistor as in case of strong winds the wind turbine will be damaged.

The reason that there are prolonged numbers of days without sun is that there is no wind to move the clouds. So when you will need wind the most there is none. At least panels still produce some energy even in worse cloudy day assuming there is no snow on the panels.

[Dave McCampbell]

Hi Dacian,

Wow!  I just watched your video on your wind turbine.  You really live out in the Canadian tundra boonies with lots of snow in the winter.  No wonder you have the time to produce all those great Electrodacus products.  Also, interesting to see the power calculations which I have never seen before.

I had a similar experience with a large Windbugger wind generator 20 years ago, but in the tropics on a cruising sailboat.  It did not produce much power, mostly because we tried to stay out of winds in the 20-25 mph range when sailing, and also because we were always anchored in sheltered spots mostly with winds less than 15 mph.  The other problem is that the best place for a wind generator is on a pole near the stern of the boat which is also the best place for solar panels.  So it sometimes shaded the solar panels which really reduced their output.

We figured the wind generator produced less than 25% of what we got from it and solar.  And at that time we only had about 400 watts of solar.  As we were always short of what we needed (around 170 ahrs a day) to keep up with our daily energy needs, we had to run the engine alternator every couple of days. 

After a 4 year circumnavigation of the Caribbean we sold the Windbugger and bought more solar.  In 2012 we went to 800 watts of solar which kept up about 98% of the time.  Now we have just added more, because we can, on our catamaran and have 1560 watts which I think will keep up even in the Mediterranean so we never have to plug into shore power.

So I agree with Dacian and Harry that a wind generator is very inefficient compared to solar, and its best to go all solar even if you live in the snowy Canadian outback.

Dave SV Soggy Paws

In Malaysia