diy solar

diy solar

Rant on terminology...

I think think both positions of the AH VS WH discussion have their merits .... WH is definitely better for comparing systems with different voltages .... but, for me, it is what your mind has gotten used to recognizing.
For instance, if you grow up your whole life thinking in Deg F and then have to start thinking in terms of Deg C.

Once you get used to thinking one way, it is hard to think the other way.

It's not one or the other though. If you do capacity testing, by all means use Ah since you eliminate errors due to losses in wiring etc. However, if tomorrow someone comes to the forum and asks "How much power (sic) do you use every day?" - makes little sense to answer "5 Ah" without a lot of context. Instead, just saying "3kWh" makes the answer very clear. I use both terms, but context matters.
 
I'm a pretty simple minded guy. As such, I like my camper's 12-volt systems to work and I like my INverter to work when the camper isn't connected to shore power (hey, we were boaters for 30 years).
So, I was reading an article that referenced eddy currents;
" Differences in SOC between batteries means that even when the load is disconnected, there will be eddy current flowing between batteries as they equalise SOC. Eddy currents can be exceptionally high and cause batteries to go into an unpredictable protection mode."
Honestly, is this one of those " don't believe everything on the internet " things? Or is there some value in it?
 
" Differences in SOC between batteries means that even when the load is disconnected, there will be eddy current flowing between batteries as they equalise SOC. Eddy currents can be exceptionally high and cause batteries to go into an unpredictable protection mode."
Honestly, is this one of those " don't believe everything on the internet " things? Or is there some value in it?

There is a current between those batteries when there is a voltage difference (and this often, but not always, indicate a difference in SoC). However, calling these currents ''eddy currents" is wrong.
 
There is a current between those batteries when there is a voltage difference (and this often, but not always, indicate a difference in SoC). However, calling these currents ''eddy currents" is wrong.
Thanks.
The person went on to talk about "branch currents" after that. I have no idea what a branch current might be.
 
" Differences in SOC between batteries means that even when the load is disconnected, there will be eddy current flowing between batteries as they equalise SOC. Eddy currents can be exceptionally high and cause batteries to go into an unpredictable protection mode."
Honestly, is this one of those " don't believe everything on the internet " things? Or is there some value in it?
The phenomenon of current flowing between two batteries of differing SOC/voltage connected in parallel is real but the term used to describe this phenomenon isn't correct.

It's a misappropriation of a specific scientific and electrical engineering term "eddy current", which has quite a different and specific meaning unrelated to the batteries in parallel scenario.

I'm not sure whether the current which flows between batteries connected in parallel has an actual electrical engineering term. I mean it's just one example of a DC circuit and is just, well, current.
 
Extending the theme on bad terminology, some others spring to mind considering we have a bit of a parallel car theme going:

Shock absorbers don't absorb shock. Suspension coils (and tyres) do that job. "Shocks" are really just system dampers.

Radiators are heat exchangers and while they get hotter than their immediate surrounds and obviously radiate some energy, radiation is not the primary means by which they dissipate heat energy. Convection is their primary means of heat transfer.

Coolant is another funny one. Coolant is not as effective at absorbing/transferring heat as water alone. That's because coolant reduces the specific heat capacity of the cooling fluid (water). Its job is to change the freezing and/or boiling points of the fluid used for system protection.
 
Hey, the Detroit Lions just one one. I mean won one. That makes one win.
 
Extending the theme on bad terminology, some others spring to mind considering we have a bit of a parallel car theme going:

Shock absorbers don't absorb shock. Suspension coils (and tyres) do that job. "Shocks" are really just system dampers.

Don’t dampers absorb or dissipate shock?

What about sway bars? My beef is calling them anti-sway bar.
 
And it makes you wonder just why foreign language speakers find english soo difficult....even the brits cant understand our english? and why can we call it english....its not its amerislang
 
To halfway get back on topic, the ones that get me are the incorrect terms thrown around regarding generator and inverter: Solar Generator, Inverter, Inverter Generator, etc:

Inverter - A device that electrconically converts DC to AC, and can be a part of a combination unit that also includes a charger and a transfer switch.

Inverter Generator, a typically gasoline though there are some diesel models generator that uses an alternator to generate power that is then rectified to higher voltage DC, and then converted to AC using electronics similar to an inverter mentioned above.

Solar Generator - A marketing term typically used to describe an undersized solar panel mated to a small battery bank with an inverter.
Please don’t add this topic to this thread.

Far too much controversy from people thinking they know the only definition of the term…
 
Don’t dampers absorb or dissipate shock?

What about sway bars? My beef is calling them anti-sway bar.
“Sway bars” are designed to keep a vehicle as level as possible in a turn… anti squat? Anti sway? Meh.
 
Absorbing shock and dissipating energy are different things.
How so?

Doesn't a resistor absorb power (I^2 * R) and then dissipates this power (or energy) through heat?

Absorbing a shock (where shock = a mechanical acceleration) means the damper is actively deaccelerating the mass. Though the term damper is more exact, I have no problem calling them shock absorbers.
 
“Sway bars” are designed to keep a vehicle as level as possible in a turn… anti squat? Anti sway? Meh.
Vernacular. Colloquialisms.
The contemporary vernacular for the behavior the sway bar was created to reduce at the time was ‘sway’ - although doing so is more accurately transferring acute suspension compression to the opposing side of the vehicle.
 
Vernacular. Colloquialisms.
The contemporary vernacular for the behavior the sway bar was created to reduce at the time was ‘sway’ - although doing so is more accurately transferring acute suspension compression to the opposing side of the vehicle.
That’s correct. A better name for sway bar is torsion bar. But anti sway bar is just stupid.
 
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