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Help with 2 setups please.

idahogal

idahogal

New Member
Joined
Oct 5, 2023
Messages
8
Location
Idaho, USA
I have two separate setups I'd like some help with. I'm fairly new, my dad connected my panels for me, but I'd like to better understand and make sure they're safely operated. I had a mishap with the mc4 connectors and melted them (my own ignorance) and now I'm more aware of potential risks.
System 1:
2 EcoWorthy 195w panels, in parallel. Currently have 2 mc4 connections on 12ga wire to an Anderson adapter that plugs into my power station (see below for link & specs)
1 IdeaPlay 2000 Power Station

questions:
Do I need a fuse/some sort of protector between the panel branch connectors and the wiring to my power box?
Can I use 10ga wire from the branch connectors to my power box? It's the only 20ft one I can find with Anderson adapter end. In case you are unfamiliar with this adapter, it looks like this
Will I get longer lasting power if I use the DC connections for things if I'm able?
Can I add any of these to my system Trina 245w panels

System 2 is incomplete
Portable 110w panel that came with a PWM controller
I would like to build a small system to power only a mini fridge. It runs about 65w when the compressor is going, and much less when it's not. Eventually I may increase demand on this, so I'd like to make sure it can have more solar input added. I am going to try to source used items from Marketplace vs buying all new stuff.

questions:
Do I need fuses/disconnects? I believe the answer is yes, just confirming.
Can I use a marine d29 battery?
I think a 1000w inverter will be sufficient? Would 2000w be too much?
Will I get longer lasting power if I use the DC connections for things if I'm able?
Can I add any of these to my system Trina 245w panels


 
You always need a safe way to disconnect the energy coming from your panels to your charge controllers or AIO inverters. Simply pulling the wires is not safe and you can have a rather large arch when trying to do so.

You would want to get some sort of disconnect switch/breaker, either 1 or 2 pole.

Here is an example of a two-pole. What would potentially work best if your situation is something like this.


For system # 2
questions:
Do I need fuses/disconnects? I believe the answer is yes, just confirming.
Can I use a marine d29 battery?
I think a 1000w inverter will be sufficient? Would 2000w be too much?
Will I get longer lasting power if I use the DC connections for things if I'm able?
Can I add any of these to my system Trina 245w panels
Click to expand...
Yes you always need fuses, preferably breakers/disconnects.
Yes you can use a marine battery so long as it's the correct voltage for your inverter.
1000W is sufficient for a mini fridge by far.
Longer lasting power? I mean you'll have a more reliable system if you use proper connectors, such as tinned copper, wire lugs, ring terminals etc with wire shrink that has a good glue for sealing your connections.

Can I add these panels, sure if you have a charge controller to hook up to them, they will work fine for connecting to a system.
 
MaikaiLifeDIY said:
You always need a safe way to disconnect the energy coming from your panels to your charge controllers or AIO inverters. Simply pulling the wires is not safe and you can have a rather large arch when trying to do so.

You would want to get some sort of disconnect switch/breaker, either 1 or 2 pole.

Here is an example of a two-pole. What would potentially work best if your situation is something like this.


For system # 2

Yes you always need fuses, preferably breakers/disconnects.
Yes you can use a marine battery so long as it's the correct voltage for your inverter.
1000W is sufficient for a mini fridge by far.
Longer lasting power? I mean you'll have a more reliable system if you use proper connectors, such as tinned copper, wire lugs, ring terminals etc with wire shrink that has a good glue for sealing your connections.

Can I add these panels, sure if you have a charge controller to hook up to them, they will work fine for connecting to a system.
Click to expand...
Thanks! I'll add disconnects to my list. This will go after the parallel Y-connectors, before my main wires, correct?
For the longer lasting power. Doesn't the conversion of DC to AC lose a lot? So if I have DC-DC connected devices (or 12v devices?), would I be able to run something longer than DC-AC plugs on the unit? For example: If I have a standard AC plug microwave, and a 12v plug microwave will they use the same amount of power or will the 12v run longer because it's not having to be converted? I hope this makes sense.
 
idahogal said:
Thanks! I'll add disconnects to my list. This will go after the parallel Y-connectors, before my main wires, correct?
For the longer lasting power. Doesn't the conversion of DC to AC lose a lot? So if I have DC-DC connected devices (or 12v devices?), would I be able to run something longer than DC-AC plugs on the unit? For example: If I have a standard AC plug microwave, and a 12v plug microwave will they use the same amount of power or will the 12v run longer because it's not having to be converted? I hope this makes sense.
Click to expand...
Yes, the breakers would go in the merged conductors that run to your inverter.

If you were to run DC only appliances yes you will get a little more run time since there is no energy lost to convert DC to AC energy. But DC is not the ideal power source for a home since you will have significant voltage drops over the distances that are needed to run wires throughout a typically sized home. You will also have a harder time finding 12v appliances versus standard AC appliances.

For example: If I have a standard AC plug microwave, and a 12v plug microwave will they use the same amount of power or will the 12v run longer because it's not having to be converted? I hope this makes sense.
Click to expand...
To answer this, if both appliances the AC and DC were the same wattage they would use the exact same amount of energy. In other words, a 1000w is a 1000w regardless of voltage or current type such as DC or AC. The only reduction in run time from your batteries would be consumed in the process of converting the DC energy to AC, however, most inverters have a very high efficiency at converting that stored energy.
 
MaikaiLifeDIY said:
Yes, the breakers would go in the merged conductors that run to your inverter.

If you were to run DC only appliances yes you will get a little more run time since there is no energy lost to convert DC to AC energy. But DC is not the ideal power source for a home since you will have significant voltage drops over the distances that are needed to run wires throughout a typically sized home. You will also have a harder time finding 12v appliances versus standard AC appliances.


To answer this, if both appliances the AC and DC were the same wattage they would use the exact same amount of energy. In other words, a 1000w is a 1000w regardless of voltage or current type such as DC or AC. The only reduction in run time from your batteries would be consumed in the process of converting the DC energy to AC, however, most inverters have a very high efficiency at converting that stored energy.
Click to expand...
you've been very helpful, thank you!
 
Try to keep the current going through an MC-4 connector down to 20 amps or less.

Officially they are rated for 30 amps, but running those connectors at near that rating has caused fires.
 
HarryN said:
Try to keep the current going through an MC-4 connector down to 20 amps or less.

Officially they are rated for 30 amps, but running those connectors at near that rating has caused fires.
Click to expand...
How would I do that? How can I control how many amps are going from the panels? Is that what a charge controller would do?
 
MaikaiLifeDIY said:
You’re welcome, any other questions feel free to ask. 👍
Click to expand...
one more (hopefully only one 🤣) Am I ok to change to 10AWG wire at the parallel connectors vs the 12AWG that's currently in use?
I have 20ft of 10AWG cable that I want to attach to the mc4 connectors outside where the parallel connects attach to the inside cable. It has the correct Anderson adapter on the other end that plugs into my battery box and I won't need any mc4 connectors inside, and won't have pieced together wire as it presently is.
 
idahogal said:
How would I do that? How can I control how many amps are going from the panels? Is that what a charge controller would do?
Click to expand...
Add up the published Isc amperage for the two EcoWorthy 195w panels you want in parallel.
If it is less than 20A on an MC-4 after combining them, it's good.

The charge controller will find the optimum amount of current to draw to maximize the power you get (MPPT).
Could be anywhere from 0 amps to Isc amps.
 
idahogal said:
I have two separate setups I'd like some help with. I'm fairly new, my dad connected my panels for me, but I'd like to better understand and make sure they're safely operated. I had a mishap with the mc4 connectors and melted them (my own ignorance) and now I'm more aware of potential risks.
System 1:
2 EcoWorthy 195w panels, in parallel. Currently have 2 mc4 connections on 12ga wire to an Anderson adapter that plugs into my power station (see below for link & specs)
1 IdeaPlay 2000 Power Station

questions:

Can I add any of these to my system Trina 245w panels
Click to expand...
Not "add". The 2 panels you have are 24.5 Voc, and the max voltage of your inverter is 44v. Putting two panels in series, the 49.0v would exceed 44v rating of the inverter. The panels in parallel (current setup) are at the max 20a of the inverter.

You could replace the 195w panels with the 245w panels. Put the two in parallel, just like the 195 panels.

Also, the max PV input is 500 watts. So going much over 500 watts doesn't help you. Consider two 300w panels to max out the system.
 
Last edited:
idahogal said:
How would I do that? How can I control how many amps are going from the panels? Is that what a charge controller would do?
Click to expand...

On the back of the solar panel, there is a label that tells what the panel is capable of producing.

The same information is in the technical data sheet of the panel - just follow the link that you posted above for that Trina panel.

Voc ( open circuit voltage )

- This number is the max voltage that the panel can produce at room temperature if the battery pack is fully charged.
- At lower temperatures, especially when sub zero, this can increase by ~ 20%
- On that panel, the Voc is 37.5 volts. Add 20% and it could hit ( 37 volts ) x ( 1.2 ) ~ 45 volts
- So now look at your power station or solar charge controller and make sure that it can handle 45 volts input into the solar panel input.

Imp - ( Max Current under ideal conditions )

- This is the current that the panel can in theory produce
- For this panel, it is ~ 8 amps

So just one panel feeding through the wire and connectors would at most push 8 amps through it.

If you have 2 panels feeding into the same wire in parallel, then it would just be ( 2 panels ) x ( 8 amps ) ~ 16 amps, so well below the 20 amps suggestion.

In the real world, usually panels produce less than their rating, and pushing it hard, some people will try to run 4 panels through it, so 32 amps in theory, but usually less. it all works until that MC-4 connector is not quite perfect or on a hot day - then things get hot and life goes downhill.
 
DIYrich said:
yes. 10awg is bigger than 12awg. Bigger is ok.
Click to expand...
alright, one more 🤣 Can I cover my panels with a heavy blanket, then just connect this10awg wire today? I'm a little freaked out about the 'under load' and would prefer to be as safe as I can.
 
idahogal said:
alright, one more 🤣 Can I cover my panels with a heavy blanket, then just connect this10awg wire today? I'm a little freaked out about the 'under load' and would prefer to be as safe as I can.
Click to expand...
When you say under load, typically that means the panels are already connected and they're sending current to your charge controller, disconnecting them at that time is dangerous and you should not do that. But hooking them up, there is no load they're under, the charge controller has to boot up and will take a few moments before it determines how much current it will start receiving from the panels. If you would like to hook your panels up during the day and want to reduce the voltage on the wires during this process, you could cover them, or even easier, just hook them up in the early morning before sunrise or after sunset.
 
MaikaiLifeDIY said:
When you say under load, typically that means the panels are already connected and they're sending current to your charge controller, disconnecting them at that time is dangerous and you should not do that. But hooking them up, there is no load they're under, the charge controller has to boot up and will take a few moments before it determines how much current it will start receiving from the panels. If you would like to hook your panels up during the day and want to reduce the voltage on the wires during this process, you could cover them, or even easier, just hook them up in the early morning before sunrise or after sunset.
Click to expand...
Yeah, I thought that was what 'under load' meant....and if they're not connected, it shouldn't be an issue...I just wanted to be extra safe :)
 
idahogal said:
Yeah, I thought that was what 'under load' meant....and if they're not connected, it shouldn't be an issue...I just wanted to be extra safe :)
Click to expand...
Actually, they produce power when not connected. As soon as your body provides a path to ground, they will happily supply current. Blanket should work. Waiting until evening is better.
 
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