Salvo
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Re: Suspension upgrade
j-d wrote: Our sway bar experience has been opposite of Salvo's observation. That's not an observation but fact! The suspension consists of springs and dampers. Do not confuse the two. They have completely different rolls in a suspension system. Rocking is due to inadequate damping. A sway bar is a torsion spring. It's not a damper. If you enter a driveway or a speed bump at an angle the sway bar will become energized. The bigger the bar the more energy the bar attains and the more rocking you'll get.433Views0likes0CommentsRe: Not a TriMetric, but for $20 might be worth trying out...
According to the spec, that meter can't measure both ways. It states 0 to 20A. If it can measure current in both directions it would state -20 to 20A. brulaz wrote: I do want the meter to measure net Ah, from both loads and charge sources.531Views0likes0CommentsRe: solar panel connectors
Yep, that's what I've been saying. A big series string resulting in a big voltage differential between a 12V battery and the operating Vmp is not a good design. You get poor efficiency. The charge controller will get hot. Better to go with a series-parallel string (if using 4 panels) or just parallel when using 3 panels. JiminDenver wrote: I've been testing the 3 250w's in series and two things. The controller gets hot bucking down those voltages and I'm losing amps in the process. Each panel peaks at 18.5a alone but peak in series is 45-50a.304Views0likes0CommentsRe: question,, which is better when looking at solar panels.??
Where is that stated. That link says exceeding 150V may damage controller. smkettner wrote: Morningstar does actually protect itself from high panel voltage. The issue is that you get no power while in protection mode. http://www.morningstarcorp.com/wp-content/uploads/2014/02/TSMPPTdsEng.pdf464Views0likes0CommentsRe: question,, which is better when looking at solar panels.??
If you put the 3 panels in series you may not outperform pwm during low sun angles. Look at the efficiency curves in the manual. At low solar output the controller efficiency is not very good. Efficiency is better when panels are in parallel. I don't understand why you want to pursue a series configuration. The 150V max rating is not to be taken lightly. 150V is the switching FET breakdown voltage. You never even want to get close to that limit. At 25C the panel has an open circuit voltage of 45.5V. Voc temperature coefficient is -0.159V/C. At 19F, or -7.2C the open circuit voltage is: Voc = 45.5V + (0.159 * (25C + 7.2C)) = 50.62V 3 panels will bring you 1.86V over the 150V absolute max limit. Do what you want, but no respectable engineer will sign off on that. 19F isn't even that cold. You don't have to be camping. The trailer could be parked somewhere. carl2591 wrote: My main purpose of this post was not to find the cheapest way to do this install. I want to do the best with a budget in mind and using the most cost effective products of quality, like morningstar products. I know there are other good lower cost products but when you read post of folks that do a lot of solar like my friend handy bob solar, you learn what is a good quality product at a good price and will do the best job for your batteries. In reading the morningstar white paper on the difference between MPPT PWM on lower watts and voltage system the PWM is the best choice. On higher voltage systems the MPPT will out perform more often with lower sun angles.464Views0likes0CommentsRe: question,, which is better when looking at solar panels.??
Instead of guessing, let's look at what's needed. The panel under discussion is 195W, Imp = 5.38A, Vmp = 36.2V. Three panels in parallel will bring cable current to 16.1A. We'll design the cable for a 1% voltage drop. Assume cable length of 30 ft (round trip). Total cable resistance is: R_cable = 36.2V * .01 / 16.1A = 22 mohm Cable resistance per foot is: R_cable per foot = 22 mohm / 30 ft = 0.75 mohm/ft 8 awg cable (0.63 mohm/ft) looks like a good fit. It costs about a quarter per foot. 30 ft costs a whopping $7.50. Are you serious the $7.50 cost is a factor to get an efficient design? Do you really think 8 awg cable is difficult to work with? I don't know Almost, you got some fuzzy logic. The OP wants to buy the cheapest panels on earth, yet you want him to purchase a $60 combiner box??? When a substitute box can be gotten for under $5? Almot wrote: Salvo wrote: One of the myths around here is that series is better than parallel because you can use smaller cable. Going to higher voltage Vmp comes at a cost. In this case, efficiency drops by 5%. Charging current will forever be 5% lower. The OP can use the same hardware and connect panels in parallel. The panel cable will be a little larger, but so what? It's not a myth :). 24V in series do use a smaller cable - much smaller, like #10 vs #4. Cable cost - higher with parallel - is only one of variables.230Views0likes0Comments
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Bucketlist destinations you just can't miss. Which spots stick with you?Jan 18, 202513,487 Posts
