Tigelowe Registered Users Posts: 9 ✭✭
Is anyone using a hydrogen detection device to turn on a vent fan in their battery room? My batteries and electronics are in an 8'x12' well house. The well house is close to air tight. I will usually open the door during the absorption stage but I am not always home to do so. I have 16 Trojan 370AH batteries charged by 3KW of solar.
The cost of a hydrogen detector is steep at around $1000. I'm looking at the 'SBS-H2' and 'HGD-2000'.
Any other ideas to control hydrogen would be appreciated.
0 · Share on Twitter
You can use a simple voltage sensor to sense the absorb voltage and trigger a vent fan from that.
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
gen: http://tinyurl.com/LMR-Lister ,
Are your batteries exposed? If so, that is an improper installation... electronics should not be in the same room with exposed batteries. The batteries should be in a box. The box should be vented to the outside of the well house.
The conduit with the battery cables should enter the battery box below the tops of the batteries... hydrogen rises and will not enter the conduit.
By the way, keeping your electronics away from exposed batteries is not just about hydrogen... sulfuric acid mist emanates from your batteries and can be a corrosive influence on your electronics and wiring (and your nasal cavities).
What controller do you have? ... some controllers have a voltage controller aux output that can power a small fan.
I'd suggest you box the batteries and passive vent them, don't forget to install an inlet vent too.
Thanks Mike, VT, Ralph,
I will box the batteries and passive vent the box.
The CCs' and AGS' energize the two DC fans installed over the battery banks when voltages are in higher ranges. Air is exhausted from the solar mechanical room to the outside.
However batterys gas at fairly predictable times, and you ought to be able to just use something from your controllers AUX system, that triggers on voltage or charge stage.
I programed my charge controller to turn on a little relay I installed when the battery voltage is above 53.5v. My inverter has the same ability.
My vent fan runs on 48v and the signal the charge controller and inverter send is only 12v thus the relay.
Conext XW6848 with PDP, SCP, 80/600 controller, 60/150 controller and Conext battery monitor
21 SW280 panels on Schletter ground mount
48v Rolls 6CS 27P
To keep things in perspective, I looked at the flammability and explosion limits (4% and 18.3% respectively) for hydrogen. I computed that to attain a dangerous mixture of hydrogen in air in a 8' x 14' enclosed area (assumed 8' ceiling) you would need to decompose about 0.6 kg of water for a flammable atmosphere or 2.6 kg of water to get to an exploseve atmosphere. That is quite a quite a lot of water.
How much time would be needed to decompose all that water at the charging conditions? I don't know but you should also consider that as the hydrogen is being evolved, some is escaping the building at a rate that depends on its tightness.
So, look at the rate at which you add water to your batteries. That is the amount of water that turned to hydrogen (and oxygen). If you add less water to your batteries every time you go check on them (thereby opening the door and letting a lot of H2 escape...), I would not worry about it.
E-mail [email protected]