MemberMarch 16, 2019 at 1:25 am
Your absolutely right about the V=IR equation, a lot can be done with it. But there are numerous factors that have to be taken into account when applying it or the result is completely wrong. For example, the resistance of an incandescent light bulb differs when the bulb is energized or not. The bulb’ s resistance changes as it gets heats up so the initial current is not the ‘steady state’ ON current.. Another example relates to my current interests: current drawn by a stairlift motor is not the current calculated by I= V/R using the resistance of a motor when not energized, it is much less. As a motor begins rotating a ‘back EMF’ builds up and causes the running current to be much less. In this case the R used in the I=V/ R would have to the the ‘virtual’ R ( a result of the back EMF) of the motor when running.
I suspect from the Genesis NP7 battery manual’s Fig.3 the stairlift’s electrical designers make use of the batteries capability to provide 21 amps for up to 3 minutes before the battery terminals drop to 11 volts. I believe the Acorn Superglide 120 batteries I’m working on draw more that 1.5 to 2 amps. How much however is the question I’m trying to get and answer to.
I appreciate your concerns about how the batteries are being charged, the fumes during charging ( hydrogen gas .very explosive ), the sulfuric acid, and disposal..Thankyou for bringing up your comments on safety concerns.. I am aware of these issues and have taken them into account. in what I am doing. I certainly would not recommend anyone trying what I’m doing without a solid electrical and mechanical background, or under the supervision of a qualifid technical person.
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