bbaker2001 wrote:
is there a monitor for the battery gases like a propane monitor.
You could probably buy one but I'd bet it's going to be expensive.
Unless you have a really abnormal charging scene, the amount of hydrogen produced is very small and is easy to vent because of it's weight differential with air. I did a bunch of searching and calculating when I built my 2-6V box. Mine is vented with a single 3/4" tube to the exterior. The chrome vent cap on the exterior has a diaphragm to prevent backflow of air. A couple of small holes toward the bottom of the box allows for air displacement.
Batteries in box:
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Full view of box:
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This box is lined with FRP plastic and has a gasket seal below the lid. It seems to be holding up well. Cables exit the bottom of the box into a 2" ABS pipe. The pipe is hung underneath the trailer and exits into the electrical distribution cabinet on the opposing side of the trailer. Total run to distribution bus with 1/0 cable is 6'.
Final picture with cowboy theme enhancement:
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