Inexpensive breakers?

[Sidvicious]

What are the drawbacks to using 2- 60 amp inline breakers (2 @ $15 each) with a switch like the one pictured below vs. a Midnite 60 amp breaker and babybox (2 @ $23 each + $50 babybox)? It would be easier to install and cheaper. I'm very limited on space even for a babybox. My main goal is to be able to switch off PV and Battery from charge controller for maintenance etc. I have two 345w panels.

 

[Skypower]

How much do you like what you own? I wouldn’t touch the pictured breaker with a ten foot pole. Definitely not for PV

 

[timselectric]

What are the drawbacks to using 2- 60 amp inline breakers (2 @ $15 each) with a switch like the one pictured below

Fire

 

[mikefitz]

Worst case, death.

 

[MarkSolar]

I used similar breakers for a PV system I have in a barn where it can get some wind blown rain through the doors. I picked them because they were water resistant and had waterproof entrances for the cabling because they were designed for marine applications. Those types of breakers seem to be designed to meet either SAE standards for cars (stereo systems, accessories, etc) or marine applications to run the 12v utilities and accessories they use. The ones I bought were rated 12-48v. So they're generally not UL rated because they're not targeted for use in buildings. I don't see why they would be less safe being rated for automobiles or boats, but if you want to be squeaky clean on the paperwork, you probably want to get something UL rated.

 

[BanjoTX]

Does the pictured breaker not function correctly?

 

[Skypower]

I used similar breakers for a PV system I have in a barn where it can get some wind blown rain through the doors. I picked them because they were water resistant and had waterproof entrances for the cabling because they were designed for marine applications. Those types of breakers seem to be designed to meet either SAE standards for cars (stereo systems, accessories, etc) or marine applications to run the 12v utilities and accessories they use. The ones I bought were rated 12-48v. So they're generally not UL rated because they're not targeted for use in buildings. I don't see why they would be less safe being rated for automobiles or boats, but if you want to be squeaky clean on the paperwork, you probably want to get something UL rated.

Many get hot or don’t even have current interrupt, it just a switch. Copper, contact alloys and mechanisms cost money and you probably won’t get the value within. There are plenty of examples here and YouTube of hot breakers. If they get hot but don’t fry, are you really saving money loosing power in regards to what you paid for the system? You’re welcome to run test on it now and years from now. I’d rather be done with it and have one less thing to worry about, whether or not it passes some bureaucracies graces.

 

[Skypower]

I like peace of mind comfort zone. I had some quality 48 volt BUSS brand breakers and thought they were pretty great. Found out that BUSS absolutely did not recommend them for a system that exceeded that by any margin (mine reaches 55.2) so I replaced and retired them. Did they fail, did they get warm? Nope never gave them a chance. You may notice that the one in use is not UL. That’s OK because I was able to open it up and realize that it’s built like a brick outhouse. As for PV breakers, I use ones that are rated for at least double the anticipated voltage. DC arcs are nothing to be messed with even at the low voltages. With any power system, you must go back and check all terminal fasteners a few days later. They always move a bit more. Loose connections make heat and that can lead to damage or fire. Call me paranoid, I’m fine with it.

 

[Mattb4]

Really like your custom built breaker boxes, Skypower. How you get such a precise cuts in the cover I have no idea.

 

[Skypower]

Scribed some lines, drilled out two opposite corners. And tried out my new Milwaukee cordless jigsaw with the plastic protective shoe on. Took my time to file out the corners and smooth out the straight runs. At least one and a half cups of coffee to ponder the next step. The tined copper buss took longer.

 

[rhino]

Where did you get the box for that breaker?

 

[Skypower]

My lugs are actually sandwiched between the breaker and buss. This gives me eight places for lugs in the future. The breaker had some raised nibs on the back that were easily filled down so the lid could fit down. Really close LOL. Take your time and fit heights. You don’t want stress on the breaker terminals.


LeMotech Waterproof Dustproof... https://www.amazon.com/dp/B075X177BT?ref=ppx_pop_mob_ap_share

1/8" x 2"x 12" C110 Copper Flat... https://www.amazon.com/dp/B0BTMD77D6?ref=ppx_pop_mob_ap_share

Fastronix 5/16" Stainless Steel... https://www.amazon.com/dp/B01LLZF7DW?ref=ppx_pop_mob_ap_share

 

[OffGridForGood]

What are the drawbacks to using 2- 60 amp inline breakers (2 @ $15 each) with a switch like the one pictured below vs. a Midnite 60 amp breaker and babybox (2 @ $23 each + $50 babybox)? It would be easier to install and cheaper. I'm very limited on space even for a babybox. My main goal is to be able to switch off PV and Battery from charge controller for maintenance etc. I have two 345w panels.

View attachment 156264

Two 345 w panels = 690 W ie pretty low energy level, but you didn't say what voltage you are working with? at 12volt this and be 57.5A (ie quite high)
on the battey to inverter to load side, you don't say what power those loads draw either. Are they lights and USB chargers or electric kettles?
I have used one of these small units for a 12v system connected to one automotive L-Acid battery and one 150W PV panel and have had no problems with it over a 5-6 year run time. That said, I use this small system for very small loads like cordless tool chargers and cell phone/computer USB, and one small LED light, so the loads are very low wattage.
These small disconnect units are designed for boats (I bought it from a boat supply place) and they are not suitable for 48 volt systems (that operate from 42-58 volts) so you need to assess.
One thing to consider, what is the risk if something 'bad' happens: is this equipment operating in your home or in a place where you leave it operational and unattended for long periods? I can say my switch has only been used in a small cabin set up with me personnally near-by during it's use, and it is off line when I leave (since I take the battery with me!) but your situation may be quite different. The cost difference to a high quality DC rated disconnect is small compared to a potential loss of property. Your stuff, your situation, your decision.

 

[tinyt]

What are the drawbacks to using 2- 60 amp inline breakers (2 @ $15 each) with a switch like the one pictured below vs. a Midnite 60 amp breaker and babybox (2 @ $23 each + $50 babybox)? It would be easier to install and cheaper. I'm very limited on space even for a babybox. My main goal is to be able to switch off PV and Battery from charge controller for maintenance etc. I have two 345w panels.

View attachment 156264

Read the bad experience i had here

 

[Sidvicious]

Thanks for the feedback folks. I'm already using a 170 amp of the same kind between my battery and the inverter based off the suggestions from the Will Prowse videos. Which have been great BTW. I'm drawing up to 2,000 watts via the inverter. Otherwise its always drawing regular 28 ft camper items like lights, fans, heater fan, etc. The inverter might be running a coffee pot and TV at one time. Although it could try to pull refrigerator, coffee pot, TV, and Microwave all at once from the inverter from time to time.

 

[Sidvicious]

Read the bad experience i had here

Thanks TinyT! It sounds like it was not a dangerous issue, but could have fried some of your equipment and did not allow the 200A it promised?

 

[Sidvicious]

I used similar breakers for a PV system I have in a barn where it can get some wind blown rain through the doors. I picked them because they were water resistant and had waterproof entrances for the cabling because they were designed for marine applications. Those types of breakers seem to be designed to meet either SAE standards for cars (stereo systems, accessories, etc) or marine applications to run the 12v utilities and accessories they use. The ones I bought were rated 12-48v. So they're generally not UL rated because they're not targeted for use in buildings. I don't see why they would be less safe being rated for automobiles or boats, but if you want to be squeaky clean on the paperwork, you probably want to get something UL rated.

Yes, it's just for a 12 volt camper system.

 

[Sidvicious]

Does the pictured breaker not function correctly?

It was just a picture for example. I don't have that one.

 

[Sidvicious]

Two 345 w panels = 690 W ie pretty low energy level, but you didn't say what voltage you are working with? at 12volt this and be 57.5A (ie quite high)
on the battey to inverter to load side, you don't say what power those loads draw either. Are they lights and USB chargers or electric kettles?
I have used one of these small units for a 12v system connected to one automotive L-Acid battery and one 150W PV panel and have had no problems with it over a 5-6 year run time. That said, I use this small system for very small loads like cordless tool chargers and cell phone/computer USB, and one small LED light, so the loads are very low wattage.
These small disconnect units are designed for boats (I bought it from a boat supply place) and they are not suitable for 48 volt systems (that operate from 42-58 volts) so you need to assess.
One thing to consider, what is the risk if something 'bad' happens: is this equipment operating in your home or in a place where you leave it operational and unattended for long periods? I can say my switch has only been used in a small cabin set up with me personnally near-by during it's use, and it is off line when I leave (since I take the battery with me!) but your situation may be quite different. The cost difference to a high quality DC rated disconnect is small compared to a potential loss of property. Your stuff, your situation, your decision.

I should have mentioned it was for a 12V system on a camper. I could be plugging a griddle into the 2K watt inverter.

I'll add better info with questions in the future. Still learning.

 

[tinyt]

Thanks TinyT! It sounds like it was not a dangerous issue, but could have fried some of your equipment and did not allow the 200A it promised?

Yes, I even replaced it with one rated at 300A and the same thing happens. When the current is between 85A to 150A, after a few minutes, the contacts open without tripping the red reset arm. One of the connection bolts get hotter than the other one and within minutes, the contacts open. Let it cool down a few minutes, the contacts close all this time without my touching the reset arm. I opened it up, cleaned the contacts and the bimetal mounting and re-assembled. Same thing.

I think my automatic pre-charge circuit immediately breaks the inverter connection to the battery preventing the bimetal from flexing some more to trip the reset arm.