My wife and I have Lectric ebikes, and we want to charge the bikes while boondocking. With out batteries being 48V & 9.6A, we think we need an inverter that is at least 500W. Can we safely plug a 500W inverter into a 12V outlet without causing a fuse to blow or starting a fire?
Thank you,
Eric
My wife and I have Lectric ebikes, and we want to charge the bikes while boondocking. With out batteries being 48V & 9.6A, we think we need an inverter that is at least 500W. Can we safely plug a 500W inverter into a 12V outlet without causing a fuse to blow or starting a fire?
Thank you,
Eric
I am pretty sure that is way too much load for a 12v socket. Does your generator work? You may want to purchase a small generator to bring along if not
Yes, our generator works, but we only need it for about 15 minutes per day while boondocking. To charge the ebike batteries, it takes about 5 hours (for each ebike).
A 500-watt inverter can pull over 40-amps, way too much for a 12-volt outlet's 10-amp capability.
It will need a fused, hardwired connection to the battery.
What is the wattage rating of the chargers? It should be listed on the device.
Will you charge one or both batteries at the same time?
Larry
Hmm...Maybe I don't need as big of an inverter as I thought. Here's the sticker on the ebike charger.
I already tried charging using a 120W charger, but it didn't work.
Any further thoughts on how I can most easily use this charger?
We'd like to charge both bikes simultaneously, but if we can't, we'll do one at a time.
With out batteries being 48V & 9.6A, we think we need an inverter that is at least 500W
Yes, our generator works, but we only need it for about 15 minutes per day while boondocking. To charge the ebike batteries, it takes about 5 hours (for each ebike).
Your battery figures indicate a storage capacity of about 461 Watt-hrs. Over 5 hrs, that is about 93 W-hrs each hour, a rate of about 8 Amps at 12V. A good 150W inverter should handle this from a cigarette lighter plug, doing only one battery at a time. For 2 batteries, this is over 920 W-hrs, or almost 80 Ahr of charge from your 12V coach batteries, so you will have to have solar or generator to replace that.
Steve
The sticker you showed says the charger draws about two amps at 100-240 VAC. Assuming 120 V, that's 240 watts. (That's for charging one battery at a time.) So you'll need an inverter with at least that much capacity--300 watts should suffice, and it will need to be hardwired to the house batteries, with an appropriate fuse at the battery end.
Steve is right in pointing out that taking 80 amp-hours out of your house batteries is a hefty chunk of power, since the standard pair of 6V batteries holds 225 amp-hours, and the rule of thumb is that it's wise not to use more than half of that (110 Ah) if you want those batteries to last. If you don't already have several hundred watts of solar panels, you may want to consider a major upgrade on the roof, unless you want to run your generator for hours each time you need to replace the power you took out of your batteries to charge up the bikes.
Understand, you wouldn't have to run it all the time you were charging the bikes; just long enough to replace the power that operation took. So if you go that route, the question is: how long does it take your converter (which is the limiting factor in charging your house batteries from the generator) to put 80 amp-hours into the house batteries? If you have one of the older converters that can only put out 30 amps or so, it may be worth considering a replacement--one of the Progressive Dynamics or similar converters that can put out 60+ amps. That could shorten your generator run time quite a bit.
If it were me, though, I'd cover the roof with solar panels (assuming you haven't already)--at least 400 watts, 600 if you can fit them.
Thanks Everyone. FYI: My coach batteries are two LifeLine 6V batteries with 220 AH each, and I have 200W of solar panels installed by Lazy Daze during manufacture.
With all of the information generously provided, here's what I'm looking to do: Hardwire a 600W inverter (so I can use two AC outlets on the inverter to charge both ebike batteries simultaneously. I would like to install the inverter behind the driver seat in my 2007 MB; however, it appears that the provided wires that run from the batteries to the inverter are only 2 feet. I'm guessing that I'll need to replace these wires with longer ones that are lower guage (thicker) wires, but how thick??? This is the inverter I'm considering (unless someone provides another recommendation): Amazon.com: VOLTWORKS 600 Watts Pure Sine Wave Power Inverter 600w DC 12V to... (https://www.amazon.com/dp/B08XXQXPWM?ref_=cm_sw_r_apan_dp_01PWKTNX13VSWHS6R7PQ&th=1)
A 600-watt inverter can draw in excess of 50-amps. I would recommend either 6 or 8-gauge wiring, along with a 60-amp inline fuse. Wiring size is determined by the potential amperage draw and the length of the round trip wiring run.
http://4.bp.blogspot.com/-_VRM_ZGUKdc/ViOeH4m70tI/AAAAAAABdd8/tp6hj68cVTg/s1600/DC%2Bwire%2Bselection%2Bchart.jpgies have more range than we do
Our experience with e-bike is that they do not need to be charged often, and our batteries have more range than we do. This might mean you do not need to charge both at the same time, allowing a smaller inverter to be used.
Larry
Hi Eric. I used a Novopal TSW inverter 2 kw(4kw surge). I liked it a lot, so I'll recommend a 1kw (2kw surge) one. A bit more expensive. The one you picked looks OK but I have no experience with Voltworks.
Welding cable is more flexible and easier to work with. The EPDM insulation is tougher than vinyl. You want to make sure it is real solid copper strands, not CCA! Copper clad aluminum wiring. Windy Nation says it is made in the USA. 4 Gauge 4 AWG 5 Feet Red + 5 Feet Black (10 Feet Total) Welding Battery Pure... (https://www.amazon.com/Welding-Battery-Flexible-Inverter-WindyNation/dp/B013DJKAKY/ref=sr_1_56?crid=1A845KNQ2T6V2&keywords=%234+welding+cable&qid=1691616564&sprefix=+4+welding+cable%2Caps%2C170&sr=8-56). If you are near the battery box I'd recommend #4 gauge. I used #2 gauge for everything. #4 should be OK for your needs.
These terminals are tinned, and have a slight funnel at the end so all of the fine strands go in easily. I found that my #2 welding cable fit in #4 terminals fine. You might test some #6 terminals to see if they fit that #4 flexible cable. TKDMR 10pcs 4 AWG - 5/16" Tinned Copper Wire Lugs Ring Terminals, Marine... (https://www.amazon.com/TKDMR-10pcs-AWG-Terminals-Adhesive/dp/B094FSTH5V/ref=sr_1_7?crid=793JUQ6U5LIA&keywords=Lion%2Bcopper%2Bterminals%234%2Bwelding%2Bcable&qid=1691617347&sprefix=lion%2Bcopper%2Bterminals%2B4%2Bwelding%2Bcable%2Caps%2C201&sr=8-7&th=1) The stud number 5/16" is to fit the posts on the inverter, your over current protection and battery terminals.
Use a good crimper. I used this one. HKS Battery Cable Crimping Tool for AWG 10-1 Copper Ring Terminals, Heavy... (https://www.amazon.com/HKS-Battery-Crimping-Terminals-Crimper/dp/B0B7S2FR93/ref=sr_1_3?crid=IM7CRKDTJL1U&keywords=copper%2Bring%2Bterminal%2BcrimperLion%2Bcopper%2Bterminals%234%2Bwelding%2Bcable&qid=1691618501&sprefix=copper%2Bring%2Bterminal%2Bcrimperlion%2Bcopper%2Bterminals%2B4%2Bwelding%2Bcable%2Caps%2C178&sr=8-3&th=1) Borrow one if you can, for as few crimps as you need. Avoid the hammer one. Harder than it looks. Not very good crimps.
Over current protection: Amazon.com: 60 Amp 12V-48V DC Inline Waterproof Circuit Breaker Manual Reset... (https://www.amazon.com/12V-48V-Inline-Waterproof-Circuit-Breaker/dp/B0BVY7NTNK/ref=sr_1_22_sspa?crid=8S2YGB9UPQVU&keywords=12v%2Bcircuit%2Bbreaker&qid=1691618810&sprefix=12v%2Bcircuit%2Bbreaker%2Caps%2C150&sr=8-22-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9idGY&th=1) No exposed metal conducting parts. Set/reset, so you can hit a button to turn it off or back on. No ring terminals. Up to #4, spacer rings for smaller wire. RonB
Eric to give you our experience using a smaller inverter…
We use starlink which uses anywhere from 4-8+ amps 12v (more at startup) including the amps used by our 300w inverter.
Specs say it pulls up to 50w on 120v.
Many people use a 300w inverter plugged into a 12v outlet for starlink.
Many devices that run on 12v have a shut off low voltage level - and the inverters seem to have this also.
If you have a load on lead acid batteries it pulls the voltage down. Distance from the battery pulls voltage down more. Other things using electricity on the same circuit pull the voltage down. If it gets too low the device turns itself off.
Our LD dc12 circuits are 20 amp, Larry said 15 amp, so check your fuses.
Our plug in inverter (standard one many starlink users use), would not work on lead acid batteries at all (shortest wire length at that time was about 30’, nothing else on it).
We switched to lithium because we were ready for this change anyway.
On lithium, even with a drop on long wires, our starlink worked most of the time plugged into any of our 12v outlets, even ones closer to 50’ long with other things running on the circuit (charging devices). But occasionally the inverter would alarm and turn off even without other things working. We put in an additional 12v outlet close to the battery (about 10’ long wire) that only has a few led lights on it and have had no problems since then.
I met someone at a caravan that bought a solar generator just to charge their e-bikes.
Jane
Guessing at wire gauges is like guessing at tire pressures. Rather than guess, you can make certain by using a voltage drop calculator (https://www.nooutage.com//vdrop.htm).
That one has a number of choices, and may look confusing at first, but here's how to use it. Start with these basic settings, which will be the same for most 12V RV wiring (other than in the engine compartment):
Voltage: 14V
System type: DC
Conductor type: copper conductor
Conductor temperature: 60C (for indoor wiring)
Conduit type: no conduit
Parallel runs: single set of conductors
Now just fill in the cable size, load current, and length of cable in feet (one way), and click the Calculate button to see the voltage drop in percent.
Bear in mind that what seems like a small percentage can be a substantial voltage drop. For example, a 3% voltage drop doesn't sound like much, but it will take you from 12 V to 11.6 V, which can be marginal for some appliances.
This is even more important if you're wiring up a battery charger or solar power system. Let's say your batteries need to be charged up to 14.3 V, and that's what your solar charge controller is putting out. But if you have a 3% voltage drop between the controller and your batteries, they will only see 13.9 V. At that rate, they may never be fully charged! So while a few percent of voltage drop may be tolerated by appliances, when it comes to charging batteries, it's best to keep voltage drop under 1%.
You should consider calling Voltworks and ask if they will honor the warranty if the battery cables are extended. Also they may be able to confirm size of new extended cables.
I like the portable solar charger idea. It always for flexibility to find the sun for charging and doesn’t expose your energy operating system to potential issues.
RonS
Lets see. The 12v outlets are fused at 10amps. That would mean 135 watts is the max the circuit could handle - no matter how many watts the inverter is rated for. And that ignores the drop as the distance to the batteries increase.
Direct connect to the batteries would be a way to go. Of course, your batteries may get drained to a level I would not be comfortable with.
E-bikes and dry camping don't seem to be all that feasible.
"I like the portable solar charger idea. It always for flexibility to find the sun for charging..."
Yes, depending upon the wattage of portable solar panels you have attached to the charger/powerpack. But a less expensive way to accomplish the same thing is to simply add portable solar panels to your rig's built-in 12V system.
A 1,000 watt-hour powerpack with 200 watts of portable solar panels (https://www.amazon.com/Jackery-Generator-Explorer-SolarSaga-Emergency/dp/B08P2Q83BY?crid=1FAX39190FLHJ&keywords=solar%2Bgenerator&qid=1691851780&sprefix=solar%2Bgenset%2Caps%2C466&sr=8-19&th=1) will run you around $1,500 to $2,000. On the other hand, you could buy a 200 watt "solar suitcase" (https://www.amazon.com/Renogy-200-Watt-Monocrystalline-Controller/dp/B07RFQVB9M?crid=82QB3KZ2H3Y3&keywords=solar+suitcase+200+w&qid=1691851956&sprefix=solar+suitcase+200+w%2Caps%2C303&sr=8-3) for $300 to $400, or build your own for less than $200 by hinging two 100 watt panels together, as I did. I use a 25 foot 6 gauge cable to connect it to my rig, which gives me plenty of flexibility in placing the panels where they'll get sunshine.
I'm using that suitcase right now, as a matter of fact. I'm in a campground where my rig is shaded by large trees (for which I'm grateful), so the 400 watts of solar panels on my roof are only providing about 300 watt-hours a day--a small fraction of their capacity in full sun. But my 200 watt solar suitcase, even though it's a little bit shaded, is putting out 350 watt-hours a day, so adding it all up, I'm doing fine.
"I like the portable solar charger idea. It always for flexibility to find the sun for charging..."
Yes, depending upon the wattage of portable solar panels you have attached to the charger/powerpack. But a less expensive way to accomplish the same thing is to simply add portable solar panels to your rig's built-in 12V system.
A 1,000 watt-hour powerpack with 200 watts of portable solar panels (https://www.amazon.com/Jackery-Generator-Explorer-SolarSaga-Emergency/dp/B08P2Q83BY?crid=1FAX39190FLHJ&keywords=solar%2Bgenerator&qid=1691851780&sprefix=solar%2Bgenset%2Caps%2C466&sr=8-19&th=1) will run you around $1,500 to $2,000. On the other hand, you could buy a 200 watt "solar suitcase" (https://www.amazon.com/Renogy-200-Watt-Monocrystalline-Controller/dp/B07RFQVB9M?crid=82QB3KZ2H3Y3&keywords=solar+suitcase+200+w&qid=1691851956&sprefix=solar+suitcase+200+w%2Caps%2C303&sr=8-3) for $300 to $400, or build your own for less than $200 by hinging two 100 watt panels together, as I did. I use a 25 foot 6 gauge cable to connect it to my rig, which gives me plenty of flexibility in placing the panels where they'll get sunshine.
I'm using that suitcase right now, as a matter of fact. I'm in a campground where my rig is shaded by large trees (for which I'm grateful), so the 400 watts of solar panels on my roof are only providing about 300 watt-hours a day--a small fraction of their capacity in full sun. But my 200 watt solar suitcase, even though it's a little bit shaded, is putting out 350 watt-hours a day, so adding it all up, I'm doing fine.
Option A is most flexible standalone option as it can be placed and moved to sunny areas but is the expensive option. Option B is less expensive and flexible but requires one to build it. Once again great suggestions and options that allow the owner to choice what is best for them. With either the inverter still must be installed to battery.
RonS
Guessing at wire gauges is like guessing at tire pressures. Rather than guess, you can make certain by using a voltage drop calculator (https://www.nooutage.com//vdrop.htm).
That one has a number of choices, and may look confusing at first, but here's how to us
This is even more important if you're wiring up a battery charger or solar power system. Let's say your batteries need to be bulk charged at 14.3 V, and that's what your solar charge controller is putting out. But if you have a 3% voltage drop between the controller and your batteries, they will only see 13.9 V. At that rate, they may never be fully charged! So while a few percent of voltage drop may be tolerated by appliances, when it comes to charging batteries, it's best to keep voltage drop under 1%.
The voltage drop calculator is easy to use and gives an exact number, I like it.
Voltage drop is tough for many to understand and why knowing the size and length of the wire runs is so important when setting up charging systems and adding high-power usage devices such as large inverters. Keeping the voltage drop low is a prime design concern, thanks for the explanation.
Larry
"Option B is twice as heavy as option A at over 70 lbs (trying moving that several times an day)and still needs the inverter installed to battery."
If by "option B" you mean a solar suitcase, I'm not sure where you got that weight. My homemade solar suitcase used two of these $75 100 watt panels (https://www.amazon.com/gp/product/B09D7BMBWP?ie=UTF8&th=1) (plus two small hinges and two drawer handles). The panels weigh 14.67 pounds apiece and the hardware weighs only a few ounces, so that's 30 pounds total. They're not hard to move around. A typical 200 watt commercial solar suitcase (https://www.amazon.com/Renogy-200-Watt-Monocrystalline-Controller/dp/B07RFQVB9M?keywords=solar%2Bsuitcase&qid=1691928864&sr=8-3&th=1) that includes its own solar controller weighs 36 pounds, but if you go for lightweight plastic panels (not as durable), a pair of 100 watt Jackery SolarSaga panels (https://www.amazon.com/Jackery-SolarSaga-Portable-Explorer-Foldable/dp/B07Q71LX84?crid=2ER73YLCTIB6C&keywords=SolarSaga+100W+Solar+Panels&qid=1691929358&sprefix=solarsaga+100w+solar+panels%2Caps%2C245&sr=8-3) would weigh 11 pounds.
"... and still needs the inverter installed to battery."
Yes, this discussion started with a question about using an inverter to power e-bike chargers. That's going to be the case regardless of how Eric replenishes the power taken from his house batteries.
"Option B is twice as heavy as option A at over 70 lbs (trying moving that several times an day)and still needs the inverter installed to battery."
If by "option B" you mean a solar suitcase, I'm not sure where you got that weight. My homemade solar suitcase used two of these $75 100 watt panels (https://www.amazon.com/gp/product/B09D7BMBWP?ie=UTF8&th=1) (plus two small hinges and two drawer handles). The panels weigh 14.67 pounds apiece and the hardware weighs only a few ounces, so that's 30 pounds total. They're not hard to move around. A typical 200 watt commercial solar suitcase (https://www.amazon.com/Renogy-200-Watt-Monocrystalline-Controller/dp/B07RFQVB9M?keywords=solar%2Bsuitcase&qid=1691928864&sr=8-3&th=1) that includes its own solar controller weighs 36 pounds, but if you go for lightweight plastic panels (not as durable), a pair of 100 watt Jackery SolarSaga panels (https://www.amazon.com/Jackery-SolarSaga-Portable-Explorer-Foldable/dp/B07Q71LX84?crid=2ER73YLCTIB6C&keywords=SolarSaga+100W+Solar+Panels&qid=1691929358&sprefix=solarsaga+100w+solar+panels%2Caps%2C245&sr=8-3) would weigh 11 pounds.
"... and still needs the inverter installed to battery."
Yes, this discussion started with a question about using an inverter to power e-bike chargers. That's going to be the case regardless of how Eric replenishes the power taken from his house batteries.
My bad I was wrong with the weight. I edited my entry. Thanks for giving your options. They give clear choices.
RonS
Let's say your batteries need to be bulk charged at 14.3 V, and that's what your solar charge controller is putting out. But if you have a 3% voltage drop between the controller and your batteries, they will only see 13.9 V. At that rate, they may never be fully charged!
It's not quite so grim: The batteries will "bulk charge" up to 13.9 volts, then taper charge all the way up to 14.3 volts (at 14.3 volts, the charging current has dropped to zero). It takes longer, but if you are using lead acid batteries, the time difference might be unnoticeable, as lead acid batteries begin taper charging (all by themselves - it's the way they operate) more slowly above 13.9 volts anyway.
"The batteries will 'bulk charge' up to 13.9 volts, then taper charge all the way up to 14.3 volts"
But in the example I gave (3% voltage drop in the wiring, resulting in 13.9 V at the batteries), the batteries will never see 14.3 V--so they will never get a full charge.
"It takes longer, but if you are using lead acid batteries, the time difference might be unnoticeable"
It's not a question of time difference; it's whether the batteries can get the voltage they need to be fully charged. In the example I gave, the solar charging controller thinks it's doing its job by putting out 14.3 V, but the batteries never see that voltage, so they cannot reach full charge.
Bottom line: if there's significant voltage drop in the wires leading to your batteries, they will never fully charge. That's why it pays to use a voltage drop calculator to determine what size wire you need.
We have Juiced eBikes which have a 52V 19.2 AH Battery. The battery charger that came with it is 52V - 2 amps. We bought a 300W 12V to 110V pure sine wave inverter which works in our car or in our 98~MB. We have a direct wired connection to our house batteries maybe 12-GA wire and we have not had any problems. Typically we use the batteries to halfway and then they take overnight to charge. There are higher amperage charging fast chargers for these bikes but then you need more inverter for them?
Karen~Liam
98 ~ MB
NinA
Amazon.com: BESTEK 300Watt Pure Sine Wave Power Inverter Car Adapter DC 12V... (http://www.amazon.com/gp/product/B07KQ4Q2L5/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1)
Bottom line: if there's significant voltage drop in the wires leading to your batteries, they will never fully charge. That's why it pays to use a voltage drop calculator to determine what size wire you need.
The key here is "if", but that requires the charging current to remain at the same amps "forever". But it won't, because the battery will continue to charge in "taper mode", and the more it charges, the lower it's charge rate. That lower amperage means the voltage drop on the wires is lower, so it's now charging (more slowly) at 14.0 volts. And so on: more charging, lower current, higher voltage, and after a few hours, it's fully charged, drawing very little current. No current, no voltage drop, and you have 14.3 volts on a fully charged battery. It's not an ideal situation, but it does allow for a full charge.
I'm using and recommend something like a Bluetti AC200 Max solar generator. It has a 30 amp receptacle so you can plug-in like using shore power when boondocking and you can charge your e-bikes without disturbing/using your house or engine batteries. With roof and or portable solar panels this gives you some redundancy that is important when RV'ing. You can get them cheaper on Ebay vs the company website.
BLUETTI AC200MAX Expandable Power Station | 2,200W AC Pure Sine Wave... (http://www.bluettipower.com/products/ac200max-power-station)
It seems much simpler to run your generator for a couple of hours while they charge up or charge up one e-bike at a time with a 150w converter.
"No current, no voltage drop, and you have 14.3 volts on a fully charged battery."
I see your point, Eric. Still, I think we can agree that it's much better to minimize voltage drop, so that the batteries get the voltage they need throughout the charging cycle.
"No current, no voltage drop, and you have 14.3 volts on a fully charged battery."
I see your point, Eric. Still, I think we can agree that it's much better to minimize voltage drop, so that the batteries gets the voltage it needs throughout the charging cycle.
A low voltage drop decreases charging time, and let's the inverter supply power more easily, so "bigger is better" has some validity. It just adds some dollars to the cable cost and makes the installation harder, working with the heavier cable. These factors will sometimes make it worth accepting slightly lower performance.
I'm using and recommend something like a Bluetti AC200 Max solar generator. It has a 30 amp receptacle so you can plug-in like using shore power when boondocking and you can charge your e-bikes without disturbing/using your house or engine batteries. With roof and or portable solar panels this gives you some redundancy that is important when RV'ing. You can get them cheaper on Ebay vs the company website.
Very interesting. I am trying to figure this out. Theoretically with a 200W solar panel it would take about 10+ hours to recharge this 2200 W unit. I looked at the 200W solar panel for this unit and it says “ Monocrystalline Solar Cells With Up to 23.4% Efficiency”. What does that mean? Will it take longer than the theoretical 10 hours?
RonS
Very interesting. I am trying to figure this out. Theoretically, with a 200W solar panel, it would take about 10+ hours to recharge this 2200 W unit. I looked at the 200W solar panel for this unit and it says “ Monocrystalline Solar Cells With Up to 23.4% Efficiency”. What does that mean? Will it take longer than the theoretical 10 hours?
It will take longer.
Solar panels rarely produce their full-rated output and the output varies according to the sun's movement, the time of the year. and the orientation of the panel. A 200-watt panel will be lucky to produce 100 watts per hour over a day's time in the summer and much less in the winter.
When mounted flat on the roof, only at the peak of summer, at noon, will they be perfectly pointed toward the sun. The rest of the year, the sun will hit at a less efficient angle.
Panels on tracking devices have higher outputs but are not usable for RVs. Tilting the panels only works well when the rig is parked in a precise east-west direction. There are a lot of variables to this.
23.4% efficiency makes it a high-efficiency panel. Most panels have a lower percentage.
Larry
"I looked at the 200W solar panel for this unit and it says 'Monocrystalline Solar Cells With Up to 23.4% Efficiency.' What does that mean? Will it take longer than the theoretical 10 hours?"
Yes, but not because of the solar cells' efficiency. In practice, that only affects the size of the panel: a 200 watt panel made with 23% efficient cells will be smaller than a 200 watt panel made with, say, 18% efficient cells. But both panels will put out the same 200 watts.
Ideally.
Standard test conditions for solar panels are roughly equivalent to "noon on June 21st under clear skies in Arizona"--in other words, as good as it gets. This isn't necessarily because manufacturers were trying to fool you; they had to pick some conditions, and it wasn't unreasonable to pick the best conditions. Anyway, that's how the power ratings are determined.
But it does mean that you'll rarely see the full rated output from any solar panel. Atmospheric haze, the sun angle and other factors affect what you get. Somewhere around 75% is a good rule of thumb.
It is possible to get full rated output, but it's very rare. I have two 100 W Renogy Eclipse panels and two 90 W Zamp panels (because that was the most wattage I could fit on my 19' Airstream's roof), and a few times I have seen as much as 410 watts from that array (at noon in May under clear Arizona skies). The panels are connected in series-parallel pairs, feeding a Victron MPPT charging controller via wiring with minimal voltage drop, so I'm taking best advantage of them... but still, it surprised me to get 410 watts from 380 rated watts of panels. I have heard that Zamp under-specs their panels, so maybe that's the reason. I'm not complaining!
But in any case, I'll say again that this kind of performance is rare, and even with my setup I have only seen it a couple of times. Most of the time I get much less. So to answer your question "Will it take longer than the theoretical 10 hours?"--yes, because even if your panels were putting out their full rated power at noon, which is unlikely, it isn't noon all day.
If you're willing to go to the trouble, tilting and aiming your panels to face the sun will help. This is much easier with portable panels, although it's a nuisance to have to reorient them several times a day. But even if your panels are aimed and angled exactly right, at eight in the morning or four in the afternoon the sun is passing through a lot more of Earth's atmosphere than at noon, so you won't get as much power.
Bottom line: Enjoy what you get from your panels, keeping in mind that after your initial investment, your cost per kWh is zero cents. 🙂
Standard test conditions for solar panels are roughly equivalent to "noon on June 21st under clear skies in Arizona"--in other words, as good as it gets. This isn't necessarily because manufacturers were trying to fool you; they had to pick some conditions, and it wasn't unreasonable to pick the best conditions. Anyway, that's how the power ratings are determined.
To be specific, panels are lab-tested under the following conditions for uniformity in ratings:
1 sun illumination, defined as 1000 Watts per square meter
Lab temperature, about 72 F - and
held there - i.e. actively cooled, since a 20% efficient panel with an anti-reflection coating will convert 80% of the incident energy to heat.
Under unusual conditions, you can see slightly more output in the performance , either due to conservative ratings or some test parameters exceeded in nature, such as a clear cold snap in June. It is rare, though, to exceed the 1 sun condition at these latitudes, and with most panels considerably off orthogonal to the direction of the sun.
Steve
[quote author=Andy Baird link=msg=251996 date=1692197821
Yes, but not because of the solar cells' efficiency. In practice, that only affects the size of the panel: a 200 watt panel made with 23% efficient cells will be smaller than a 200 watt panel made with, say, 18% efficient cells. But both panels will put out the same 200 watts.
[/quote]
The size and weight of today's panels are much lower than the one used 20 years ago. The 100-watt Renogy panel that recently replaced our LD's 85-watt Factory panel was half the weight and much smaller overall. The best part is how inexpensive the panels are today, I paid around $300 each for 80-watt panels twenty years ago.
It's a great time to cover a RV's roof in solar panels.
Larry
"The size and weight of today's panels are much lower than the one used 20 years ago."
Tell me about it! When I bought Skylark in 2006, the best 100 W panels on the market were AM Solar's 21.5V AM100 panels, specially made for them to take advantage of the then-new MPPT charging controllers. Those things were monstrous! I still have two in storage, and they're nearly twice the size of Renogy's 100 W Eclipse panels, my current favorites for minimum size per watt.
I installed a 600W inverter directly to the house batteries using 4 foot long 4 guage wires, and it's working just fine.
I'm pretty much sure of the answer, but I'm wondering if my thick wires have enough capacity that I don't need to intall the 60A circuit breaker I already bought.
Yes...it's my laziness driving this question. If needed, I'll buy something to cut the wire and install the breaker. Just thought I'd ask others first.
You always need overcurrent protection at the power source, in case of a short circuit down the line. The thing to keep in mind is that you need to protect the wire, not the load at the end of the run. The question here is "how large a breaker?"
Your AWG 4 cable can safely carry between 125 and 160 amps, depending upon its temperature rating. (See ABYC ampacity table (http://assets.bluesea.com/files/resources/reference/21731.pdf) and match against your cable's temperature rating: 75°, 90°, or 105° C.) Your inverter will draw about 55 to 60 amps, so your AWG 4 cable is more than adequate.
But a 60 A breaker would leave you no margin for startup surge (and most inverters take a considerable surge when turned on). An 80 amp (https://www.amazon.com/Blue-Sea-Systems-Circuit-Breakers/dp/B005BI5466?th=1) or 100 amp (https://www.amazon.com/Blue-Sea-Systems-Circuit-Breakers/dp/B0051P01BW?th=1) breaker would be a better choice.
Thank you very much, Andy. I will install the 100A version, because the manual of the 600W inverter says the peak power is 1200W.
You always need overcurrent protection at the power source, in case of a short circuit down the line. The thing to keep in mind is that you need to protect the wire, not the load at the end of the run. The question here is "how large a breaker?"
Andy is absolutely correct that a fuse/breaker is needed to protect the wire and not the load. But in this case, the wire size is so large and the power source (battery) for all practical purposes is unlimited, sets up a potential hazard. If a short were to occur and there was no fuse/breaker in the line, the wire may survive but the battery certainly would not and may even explode. So yes, it’s mandatory to install a fuse or breaker.
- John
I purchased the AC 200 Max bundle. FYI-the items ship separately. We charge my wife’s eBike battery overnight without issue. Both the battery and bike are chained to the rig.
Hi Chris; Don't put too much trust in a regular chain. The Bike will disappear overnight. Chain cutters are pretty quiet. I purchased this to wrap around my catalytic converter: VULCAN Security Chain - Premium Case-Hardened - 5/16 Inch x 9 Foot (+/- 1.5... (https://www.amazon.com/Vulcan-Case-Hardened-Security-Chain/dp/B07GK7JLGC?pd_rd_w=DV02z&content-id=amzn1.sym.528bfdfa-ea96-478b-a7d9-043e650836af&pf_rd_p=528bfdfa-ea96-478b-a7d9-043e650836af&pf_rd_r=98JPCVCT9B83VWDT72XZ&pd_rd_wg=uXXU2&pd_rd_r=90e880c6-3d29-448e-987c-3be04679b646&pd_rd_i=B07GK7JLGC&psc=1&ref_=pd_basp_d_rpt_ba_s_2_cp_t) This doesn't include a lock. I would check out consumer reports or bicycle club news for well rated locks.
Small electric battery powered grinders are noisy but fast also, and easy to conceal. The battery should be inside your rig while charging, although these bicycle batteries are designed to be compact and light weight. Not the LiFePO4 RV batteries that are designed to be less flammable than electric car (bike) batteries. RonB
Security of bikes is essential. E-Bikes are expensive and need to be locked up with as much heft as possible.
I realize this thread is not necessarily about bike security, but as such I would be remiss not to mention it since the topic has been brought up.
We have several non-e-bikes that travel with us. Trek bikes are highly regarded and pricey. I use ABUS products to secure them all. When on the bike rack I first secure the inner most bike with the ABUS U-Lock. All other bikes are secured with an ABUS heavy gauge chain (no cables since any bolt cutter will slice right through them) and secure through all body and wheel parts running through the U Lock and finally locked with a long shanked ABUS lock.
Here are links to the ABUS products I purchased on Amazon.
ABUS 37/55MB50 KA Granit Alloy Steel Padlock Keyed Alike (Code 5544653) with... (https://a.co/d/7AIwVS5)
Amazon.com : ABUS Granit X-Plus 540 + USH Brkt 300mm LS Shackle U-Locks :... (https://a.co/d/8MKbgvj)
Amazon.com: ABUS Hardened Steel 8KS 6 Foot x 5/16" Thick Square Security... (https://a.co/d/412wOCr)
https://a.co/d/iLvPtCc
Five years later and thousands of miles later the bikes are still with us. I am not sure but I would guess that the amount of security sends would be thieves elsewhere.
Keep them safe.
Kent