100w single panel setup advice for shed

dm6156

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I measured my dawn to dusk security light in daylight, it measured 0.5 Watt (spec doesn't list off, only on and that is 30watt). The shop light on measured 53.5 watt (spec says 60).

The issue I'm running into is the inverter. the specs says no load is 0.6 watt. This doesn't seem to be the case. I haven't measured it, as i don't have a clamp meter. Even with the lights unplugged with the inverter on, i can watch the battery voltage drop on my multimeter - in a few minutes (maybe 5) it does 0.2V.

I found a few websites andv you tube videos the show other inverters being around 5amp no load when specs listed .<0.6.

Even with no sun, the pwm controller with 100W panel was able to recover the used voltage in a few minutes (little more than the inverter was on).

I'll try to see if i can find a lower Amp no load inverter. And I'll have a clamp meter tomorrow to test the inverter with no load and with the security light at 0.5watt.

If anyone has a suggestion for inverter, I'd appreciate it.

Thanks
Dan
 

dm6156

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Adding a panel or two makes more sense
I am going to add a 200W panel to my existing 100W panel as well as add another 100aH battery to my current 100aH. Also I'm going to switch from 30A PWM to 40A MPPT. The 40A controller isn't much of a cost difference so why not go with extra 10A.

In addition, I'm going to see if i can find a lower no load inverter. First mine is over 10 years old, probably older. Second I've seen real world numbers (specs were proven with a meter) of inverters with about 0.6A no load. Third, my system is mostly a no load system - it's is a shop light that is rarely used and a dawn to dusk motion light that's rarely used as well. It will mostly be activated by wildlife.

After the upgrades are done, i can see real world numbers and start planning and researching the 12v landscape lighting i want for the area.

Thanks

Dan
 

GLC

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I have a 5000 watt inverter that uses 45 watts at idle and I have a 4000 watt inverter that uses 4 watts or less at idle. They are all over the spectrum.
 

dm6156

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There’s a thread here with results from a bunch of inverters. I’m like 30W idle on a pure sine 1200W
Thanks. I'll see If I can find that.

I don't need anything that big. My current inverter is 400W - I'm only powering low(er) voltage lights (90W total (60+30) per specs).
I haven't tested the dawn to dusk motion light when on, but at idle it's .5W (per watt meter) and specs say 30W.
The shop light is 53.5W (per watt meter)

I've got a clamp meter that can measure AC and DC, I'll measure the inverter today. I've found some on amazon that have stated of 0.2A and 0.3A (specs vs real is another story as the specs on my current one say 0.6A)

Thanks

Dan
 

dm6156

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Thanks. I'll see If I can find that.

I don't need anything that big. My current inverter is 400W - I'm only powering low(er) voltage lights (90W total (60+30) per specs).
I haven't tested the dawn to dusk motion light when on, but at idle it's .5W (per watt meter) and specs say 30W.
The shop light is 53.5W (per watt meter)

I've got a clamp meter that can measure AC and DC, I'll measure the inverter today. I've found some on amazon that have stated of 0.2A and 0.3A (specs vs real is another story as the specs on my current one say 0.6A)

Thanks

Dan
The inverter is running about 2A, 2.5 with the security light on. Way more than the 0.6.

While I was testing the inverter, I was took a couple peeks at the stats and saw 58W at 3.64A and 59W at 4.38A charging and battery was fully charged (boost mode). I'll check again later this evening and see what happens.

Thanks

Dan
 

12VoltInstalls

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While I was testing the inverter, I was took a couple peeks at the stats and saw 58W at 3.64A and 59W at 4.38A charging and battery was fully charged (boost mode). I'll check again later this evening and see what happens.
If I read this right that is not an indication of inverter consumption. That is skewed by BOTH the load and the float output of the inverter (which is a given low-amp overvolt charge that would occur without a load) plus maybe 15% inverter inefficiency.

You have to measure the actual inverter no-load amps at the cables to see actual consumption. However, from what you describe I would guess (with a good chance of being wrong) that your inverter consumption is minimal. But that’s mostly a guess with assumptions.
You have to measure it.
 

dm6156

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If I read this right that is not an indication of inverter consumption. That is skewed by BOTH the load and the float output of the inverter (which is a given low-amp overvolt charge that would occur without a load) plus maybe 15% inverter inefficiency.

You have to measure the actual inverter no-load amps at the cables to see actual consumption. However, from what you describe I would guess (with a good chance of being wrong) that your inverter consumption is minimal. But that’s mostly a guess with assumptions.
You have to measure it.
I did check the positive cable from the battery to the inverter with clamp meter with no load (inverter on, both lights off). I also checked the wire to both lights and the numbers i got on the clamp meter matched what I got on the watt meter for each light indivdually.

With the security light on, the clamp multimeter showed 2.5A (2A inverter + .5 security light). The 0.5A matched the watt meter
With the security light off, the clamp multimeter showed 2.A (inverter only)

Thanks

Dan
 

MrNatural22

🌞SW sunshine =⚡️⚡️lit up thru the darkness✌️
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Just my .02.....:unsure:
I might have missed this as I didn't read all threads but,
I would run all dc interior and exterior lighting and simply eliminate the inverter and any losses.
I run two exterior LED floodlights dusk to dawn all year long and one LED interior light in the garage when needed using one 100w renogy panel and a 12v 40ah LiFepo battery
with plenty of power to go.
I use My Victron smart solar MPPT load output to control the dusk to dawn operation.
So much simpler
 

dm6156

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Just my .02.....:unsure:
I might have missed this as I didn't read all threads but,
I would run all dc interior and exterior lighting and simply eliminate the inverter and any losses.
I run two exterior LED floodlights dusk to dawn all year long and one LED interior light in the garage when needed using one 100w renogy panel and a 12v 40ah LiFepo battery
with plenty of power to go.
I use My Victron smart solar MPPT load output to control the dusk to dawn operation.
So much simpler

What security light do you have that is 12v?
Thanks

Dan
 

MrNatural22

🌞SW sunshine =⚡️⚡️lit up thru the darkness✌️
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What security light do you have that is 12v?
Thanks

Dan
Here are the two types that I have Had great luck with and are almost three years old. The rectangle type only use 18w ea and use very little power very bright.
The round ones use 27w but cover a bigger area.
I use them also on my RV for switched outside lighting.

These are also commonly used on the rear of my 11yd cement mixer for illuminating concrete pours at night. ☀️

There are many different styles of these off road automotive lighting that function very well for 12v solar security lighting. ✌️

C01278A6-E8D0-4858-A448-602C6438EB9C.png855AB9F2-4718-437A-BBAF-5B3CB58BA825.png
 
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dm6156

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Ah, I see. I am more interested in a light that has sensor for dawn to dusk and not have lights on all night long. I've used similar light on past vehicles.

The 12v landscape lighting i mentioned would be for around my patio/firepit that isn't too far from the storage shed and currently uses individual solar lights which I'd like to replace.

thanks

Dan
 

12VoltInstalls

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interested in a light that has sensor for dawn to dusk
I think I mentioned in this thread or another that there are 12V photocells and IR motion sensors out there.
Not only that, but many (most?) charge controllers have either a trigger or actual load output that turns off at sunup and back on at dusk. A lo/hi relay can even switch 120V circuits.
 

MrNatural22

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Ah, I see. I am more interested in a light that has sensor for dawn to dusk and not have lights on all night long. I've used similar light on past vehicles.

The 12v landscape lighting i mentioned would be for around my patio/firepit that isn't too far from the storage shed and currently uses individual solar lights which I'd like to replace.

thanks

Dan
The dusk to dawn operation is built in to most charge controllers load connections, even the cheap pwm controllers by sensing thru your solar panel if it’s night or day and powering lights on and off.
Most controllers even have a timer option you can set for other
Light control.
Or you could spend money on a 12v photo eye but why? Your charge controller is all you need😉
 

Rednecktek

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The dusk to dawn operation is built in to most charge controllers load connections, even the cheap pwm controllers by sensing thru your solar panel if it’s night or day and powering lights on and off.
Most controllers even have a timer option you can set for other
Light control.
Or you could spend money on a 12v photo eye but why? Your charge controller is all you need😉
Unless you live in the PNW and then you need the 12v photo eye because your SCC thinks it's night for 4 months straight. :)
 

dm6156

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Unless you live in the PNW and then you need the 12v photo eye because your SCC thinks it's night for 4 months straight. :)
:eek:

The PWM controller I currently have, does not have that feature. However, the MPPT controller I ordered does.
That maybe the way to go with landscape lighting I plan on adding.

Now I wait until everything is delivered.

Thanks

Dan
 
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