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First timer 200 watt system ? about fuses, breakers OK to use?

Stangit60

New Member
Joined
Sep 27, 2022
Messages
7
Location
Arizona
Hello everyone, I've been lurking this forum and watching Will's videos. I like his basic 400 watt build but am testing the waters with a 200 watt system. I plan on using this to power some tools and as a backup (no grid for 4 days last year 3 this year) to intermittently power a few things like these -
1- 20' box fan
1- DC powered DIY a/c I made out of a 48qt cooler for summer
1-800 watt AC heater in winter?
1- 32" TV
1- OTA antenna
1- small ISP router
Charge 1 laptop battery
Charge 2 cell phones.

I purchased a Renogy 200 watt system
with 30 amp Wanderer Li SCC
BT-1 attachment to set battery parameters
Redodo 100ah Lifepo battery
Krieger 2000 Watt (4000 watts peak) PSW Inverter
I also have a
12V Panel W/Dual USB,Volt meter,12V cig, on/off switch
and a 12 Volt 100 Amp 6 circuit Fuse Box with Bus Bar

I plan on installing this on a 1/2" board then install that on a 2 wheel hand cart for portability. Everything will be wired close together like Wills 400 Watt setup with short cable runs no longer then 2ft one way (4ft roundtrip)
I did choose the same AWG wires that Will used in his 400 Watt tutorial. I think the fuses I have are too big for the amp capacity of the wires? If so, should I go with smaller fuses or larger wires? Here's what I got.

Battery cables - 2AWG length = 4ft total
Inverter cables- 4AWG length = 4ft total
250amp ANL bolton fuse at the Battery
250amp breaker from Battery to 2000 watt Inverter
40amp fuse for 30 amp scc
Battery master disconnect switch

I'm dizzy and confused with so many different on line calculators. I was planning on putting this all together this week. I sure would appreciate opinions and pointers from you guys if I can use these fuses, breaker and wires I have on hand. Thanks very much in advance - JC
 
Hello everyone, I've been lurking this forum and watching Will's videos. I like his basic 400 watt build but am testing the waters with a 200 watt system. I plan on using this to power some tools and as a backup (no grid for 4 days last year 3 this year) to intermittently power a few things like these -
1- 20' box fan
1- DC powered DIY a/c I made out of a 48qt cooler for summer
1-800 watt AC heater in winter?
1- 32" TV
1- OTA antenna
1- small ISP router
Charge 1 laptop battery
Charge 2 cell phones.


I purchased a Renogy 200 watt system
with 30 amp Wanderer Li SCC
BT-1 attachment to set battery parameters
Redodo 100ah Lifepo battery
Krieger 2000 Watt (4000 watts peak) PSW Inverter
I also have a
12V Panel W/Dual USB,Volt meter,12V cig, on/off switch
and a 12 Volt 100 Amp 6 circuit Fuse Box with Bus Bar

I plan on installing this on a 1/2" board then install that on a 2 wheel hand cart for portability. Everything will be wired close together like Wills 400 Watt setup with short cable runs no longer then 2ft one way (4ft roundtrip)
I did choose the same AWG wires that Will used in his 400 Watt tutorial. I think the fuses I have are too big for the amp capacity of the wires? If so, should I go with smaller fuses or larger wires? Here's what I got.

Battery cables - 2AWG length = 4ft total
Inverter cables- 4AWG length = 4ft total
250amp ANL bolton fuse at the Battery
250amp breaker from Battery to 2000 watt Inverter
40amp fuse for 30 amp scc
Battery master disconnect switch

I'm dizzy and confused with so many different on line calculators. I was planning on putting this all together this week. I sure would appreciate opinions and pointers from you guys if I can use these fuses, breaker and wires I have on hand. Thanks very much in advance - JC
1) Inverter (inverter has conversion loss) is 2000W 12V, so 2000W/0.85 = 2353W DC input power, 2353W/10V = 235A (214A if low Voltage is at 11V, 235A x 1.25 = 293A (267A @11V) breaker, so you will need 300A fuse/breaker, the wires will have to be able to handle the current too.

About the loads and run time calculation:
1)We need more details about the devices power consumption and how many hours a day they will be in used to determine how long you can run your loads using your because your battery 1280Wh battery.
2) The inverter will have power conversion loss, when converting the DC to AC, so for example you want to run 800W heater full on, to get 800W of power the DC power on the input side of the invertert = 800W /0.85 = 941W, that means you will get a little 1 hour of run time (depend on how much it cycle on and off to keep steady temperature) using your 1200Wh battery.
 
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Yes, the watt hog heater smh that's why I put that ? mark on that one. Perhaps when I get another battery. I have a watt meter that just arrived that I will measure the watt usage of things with today, but I have a some averages of watt usage of the appliances until I take accurate readings. Some things I will only use for short duration time like laptop, router etc but I just put down 3 hrs of use each for these things.

tv- 3hrs x 45 wtts = 120 hrs
antennae- 3 x 10 = 30
laptop- 3 x 55 = 165
router - 3 x 7 = 45
fan - 3 x 50 = 150
DIY AC 3 x 96 = 288
--------------------------------------------
3 x 263 = 789 W/hrs

Would this be total watts @ 3HRs * 263W = 789 Watt hrs.
Taking account of the inverter conversion loss of 0.85
789/0.85= would be 928 watts? Am I adding that right? If so, that would leave the battery little less then 1/3 capacity left? 1280 - 928 = 352
after 3 hr usage of those things.
Sorry for the trouble, thanks for the help.
 
Yes, that's more or less right. I don't see your solar panel wattage listed. You can expect anywhere from ~1h peak equivalent, maybe less on a miserable rainy day to 7hr+ on a good day. If you want to run those every day, you'd need panels to produce nearly on even the worst day. Still, for occasional shop use to get your feet wet, that's an intelligent beginning.

Oh, and you're probably better off taking the inverter efficiency off before comparing - 1280*.85=1088 AC watt hours. However, you also have to account for inverter idle. If you power it on for three hours to run those things for three hours, that's correct. If you want to leave it running, you've probably got 27W+ idle. In 24h thats 27W*24h=648 battery watthours.
 
Awesome - a "learner" bank. Don't expect to get it 100% right the first time out. But you're on the right track. Keep it fun and take a break when the head starts to spin. :)

I don't see any tools, but I suppose you have an LFP charger (not one designed for lead-acid that may contain desulfation pulses), maybe a little clamp-on ammeter, and a multimeter. No need to go bananas with the tools, just avoid the shirt-pocket cheapies, or something like that has been kicking around in the toolbox for 20 years.

Some like to pick up a plug-in "kill a watt" meter at the output of the inverter.

Fun times ahead!
 
Yes, that's more or less right. I don't see your solar panel wattage listed. You can expect anywhere from ~1h peak equivalent, maybe less on a miserable rainy day to 7hr+ on a good day. If you want to run those every day, you'd need panels to produce nearly on even the worst day. Still, for occasional shop use to get your feet wet, that's an intelligent beginning.

Oh, and you're probably better off taking the inverter efficiency off before comparing - 1280*.85=1088 AC watt hours. However, you also have to account for inverter idle. If you power it on for three hours to run those things for three hours, that's correct. If you want to leave it running, you've probably got 27W+ idle. In 24h thats 27W*24h=648 battery watthours.
That's alot of idle usage on the inverters part that can add up smh. Good to know, I'll remember that. Every bit counts when one has to depend on it. Haven't received the inverter yet it's due in a few days. Thanks for that info. The solar panels are the RNG-100D-SS wattage is listed at 100 W X 2 = 200 but was told to expect like 160-180 or so. We get ALOT of sunshine out here in AZ and am grateful for that in this situation, but I read the panels won't be as efficient in temps approaching the 110 degree temps. I plan to build panel angles to adjust them for the seasons and attach them to a cart of some sort to be able to move them around. I measured the appliances in my room before checking back here, like the TV, fan lamps, laptop, 5000 BTU window AC, TV antennae amplifier, etc to have a complete audit of those things. I'm running around the house checking everything putting my new meter to use. Some surprising numbers from the Poniie watt meter. So much idle draw of things that are supposedly "off". I have some power strips for those things, but can one install an on/off switch to shut down the inverter when not in use for AC things to avoid that?
 
Power ON/OFF switch of the inverter is OFF then it will barely draw current, if you have it ON but no AC loads then it draw what ever the spec of the inverter is with no load.
 
Awesome - a "learner" bank. Don't expect to get it 100% right the first time out. But you're on the right track. Keep it fun and take a break when the head starts to spin. :)

I don't see any tools, but I suppose you have an LFP charger (not one designed for lead-acid that may contain desulfation pulses), maybe a little clamp-on ammeter, and a multimeter. No need to go bananas with the tools, just avoid the shirt-pocket cheapies, or something like that has been kicking around in the toolbox for 20 years.

Some like to pick up a plug-in "kill a watt" meter at the output of the inverter.

Fun times ahead!
Yes I ordered a Lifepo charger that should arrive soon and I have a new meter and yep it's a cheapo smh, from HF. I got the battery delivered last week and it read the voltage at 13.14 which is like 50% SOC like the battery maker said it would be when it arrived. Since I didn't have the Lipo charger, I hooked it up to the SCC and then the panels and charged it yesterday. I'm waiting for Redodo to email me back the charge parameters. The definitions on the BT-1 app are different from what's in the Redodo battery manual and the Lifepo default settings on the Renogy Wanderer Li are said to be too aggressive. But yes, I'm having fun at this and enjoy learning new stuff. Thanks for the encouragement.
 
Power ON/OFF switch of the inverter is OFF then it will barely draw current, if you have it ON but no AC loads then it draw what ever the spec of the inverter is with no load.
Well that makes sense. I suppose I've become distrustful of stuff being "off" when it really totally isn't. Hey, Just to be sure, with the limited use of the things I listed in my OP, the 2 AWG for the battery the, 4AWG wiring for the inverter and the 250 ANL fuse and 250 amp breaker are ok for me to use? I want to jump on this project and put it together asap.
 
Bud is correct. You'll probably see somewhere in the low mA draw with the inverter nominally off, zero if there's a hard switch. First guess would be ≤20mA lost to input capacitor leakage and safety bleed resistor. That won't be in the spec, but it's something you can measure if you really want to. Do not connect through a multimeter to measure this without a precharge circuit, as you're pretty much guaranteed to blow its internal fuse. The number I gave is indeed inverting no-load, and something you should take from the inverter specs for detailed calculations of runtime.

For regular use of a hard switch a precharge resistor - can be as simple as an incandescent lightbulb - is nicer to your switch. For 12V you'll probably be OK without it.

Here is a resource for wire sizing: https://diysolarforum.com/resources/calculating-inverter-dc-wire-fuse-size.270/ You're a bit undersized for max inverter load, but if you've already got terminated wires there's no reason you can't hook it up and start playing with the loads you've described. A startup surge that overloads the wire a bit won't cause a fire, but could potentially cause a voltage sag enough to trip the inverter low voltage point. I've started larger 110V motors on a 2kW inverter just fine with a couple short #4-6 (I forget what they are) from batt to inverter. Been in place for a couple years.
 
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