i have 3 230W 41V panel in series. can i use this as the breaker or disconnect? https://www.amazon.com/ZOOKOTO-12V-...keywords=12v+dc+breaker&qid=1595134839&sr=8-6
DC breaker
- Thread starter gpower07
- Start date
No. Voltage is too high. It will not function as a breaker.
I suspect your current is under 10A, so these would be better:
If you're under 7A, a 10A would be fine too.
Breakers need to be rated for voltage as higher DC voltage takes more force to separate the contacts.
I suspect your current is under 10A, so these would be better:
If you're under 7A, a 10A would be fine too.
Breakers need to be rated for voltage as higher DC voltage takes more force to separate the contacts.
With 3 panels no breaker or fuse is needed. The wires can handle the full short circuit amperes. Voltage drop is always a problem with solar charging systems. Fuses and breakers add resistance. A heavy duty switch will add the least resistance. Blue Sea makes the best. They also have proper DC breakers if I didn't convince you. https://www.bluesea.com/products/category/11/37/Manual_Battery_Switches/m-Series https://www.bluesea.com/products/category/14/Circuit_Breakers
I recently bought this 2 pole but haven’t put it in service yet.
Circuit Breaker 2P 250V 16A Low-voltage DC Miniature Circuit Breaker For Solar Panels Grid System Din Rail Mount - - Amazon.com
Circuit Breaker 2P 250V 16A Low-voltage DC Miniature Circuit Breaker For Solar Panels Grid System Din Rail Mount - - Amazon.com
www.amazon.com
Ampster
Renewable Energy Hobbyist
Just to clarify that would be 1.25 times the load. The wire size should be matched to the breaker.
I suggest being careful with inexpensive breakers claiming high DC voltages. I tried this one, for example
VictorsHome Miniature Circuit Breaker Low-Voltage DZ47-63 1 Pole 16A 230V 400V DIN Rail Mount C16: Amazon.com: Industrial & Scientific
VictorsHome Miniature Circuit Breaker Low-Voltage DZ47-63 1 Pole 16A 230V 400V DIN Rail Mount C16: Amazon.com: Industrial & Scientific
www.amazon.com
Unless they *explicitly* state the voltage rating is DC, I would assume it is an AC voltage rating and that they are being misleading on purpose.
I do have a 30a and a 10a of the Midnight brand the OP listed (which only claims 150vdc btw) and they work fine (well, at 55vdc at least).
That’s why I avoided the VictorsHome crap.
If you follow the model number on the one I posted it leads you here:
No guarantee it’s exactly the same but it gave me more confidence.
And it states compliance with the same IEC code that the Schneider does.
And yes, it explicitly states DC of course as well.
You may not have looked before your reply but please take a look at the link I provided and let me know if you see any issues.
If you follow the model number on the one I posted it leads you here:
No guarantee it’s exactly the same but it gave me more confidence.
And it states compliance with the same IEC code that the Schneider does.
And yes, it explicitly states DC of course as well.
You may not have looked before your reply but please take a look at the link I provided and let me know if you see any issues.
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The original one you posted looks fine, if its ratings are honest. The description specifically says it's rated at 250v AC or DC, and is designed to extinguish arcs effectively. Yeah it looks like it's made by Schneider (or as a worst case, is a counterfeit) based on your search. Interesting that the Schneider link you gave lists the unit as 125v. I'd probably go with that rating!
It would be nice if some entity would test DC breakers and rate them. I think there's plenty of audience for that info nowadays. Even just 1) max voltage w/o arcing, 2) accuracy of amperage tripping, and 3) estimation of the number of switch cycles that the unit could sustain, would be handy info to base purchases on.
It would be nice if some entity would test DC breakers and rate them. I think there's plenty of audience for that info nowadays. Even just 1) max voltage w/o arcing, 2) accuracy of amperage tripping, and 3) estimation of the number of switch cycles that the unit could sustain, would be handy info to base purchases on.
WoodsieLord
New Member
I'm going to ask something silly: What's the difference between typical AC breakers and those DC breakers ? I've noticed some years ago while replacing batteries for a few Emerson 6KVA UPS at work that the battery packs have common Breakers with them. Those Emerson are 240V DC (each pack has 20x 12V 3A SLA batteries in series)
heatwave
Harvesting Mojave Sun Daily
To OP, no do not use that type breaker you showed from the panels to the CC. I stick with Midnight Solar personally for years now, though yes Schnieder are solid agreed.
I would venture to say it is standard practice, safer and easier to manage a solar system when breakers are in place from pv -> CC, CC->batts, Batts -> inverter. Commissioning and maintenance are less tedious with these breaks in place for shutting down and starting the system in proper sequence. Overloading the CC could cause damage to circuits I have found.
I would venture to say it is standard practice, safer and easier to manage a solar system when breakers are in place from pv -> CC, CC->batts, Batts -> inverter. Commissioning and maintenance are less tedious with these breaks in place for shutting down and starting the system in proper sequence. Overloading the CC could cause damage to circuits I have found.
Not silly at all WoodsieLord. Sounds like those Emerson breakers were good ones.
DC breakers have different internal designs for the section around the "contact points" that break and reconnect the electrical path. The different design costs a little more to manufacture.
For "alternating current" the electrical current flow direction switches 60 (or 50) times per second, and so the voltage briefly drops to zero that many times as well. This nearly completely prevents the electrical "arc" that can form when current tries to continue flowing when a gap is opened in the electrical path. For "direct current", the current moves continuously in one direction, and never drops to zero. So, especially at higher voltages, this is a problem because if you open the path (like in a switch or a breaker), then the arc that occurs will tend to continue, unless it is "extinguished" by making the opening wider, or some other method. Over time, repeated arcs "burn" the contact surfaces of wherever the path has been opened, and cause the contact points in the switch or breaker either to overheat under a load, or even to stop passing current. There are different methods used to extinguish the arc, but the basic point is, DC switches and breakers need this extra capability.
You can often use DC switches for AC circuits, but not vice-versa unless the manufacturer says it's ok. E.g. you'll frequently see switches rated for both AC and DC, but the DC rating will be much lower than the AC rating.
DC breakers have different internal designs for the section around the "contact points" that break and reconnect the electrical path. The different design costs a little more to manufacture.
For "alternating current" the electrical current flow direction switches 60 (or 50) times per second, and so the voltage briefly drops to zero that many times as well. This nearly completely prevents the electrical "arc" that can form when current tries to continue flowing when a gap is opened in the electrical path. For "direct current", the current moves continuously in one direction, and never drops to zero. So, especially at higher voltages, this is a problem because if you open the path (like in a switch or a breaker), then the arc that occurs will tend to continue, unless it is "extinguished" by making the opening wider, or some other method. Over time, repeated arcs "burn" the contact surfaces of wherever the path has been opened, and cause the contact points in the switch or breaker either to overheat under a load, or even to stop passing current. There are different methods used to extinguish the arc, but the basic point is, DC switches and breakers need this extra capability.
You can often use DC switches for AC circuits, but not vice-versa unless the manufacturer says it's ok. E.g. you'll frequently see switches rated for both AC and DC, but the DC rating will be much lower than the AC rating.
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Here is the link again so it’s not conflated with the one Fred is talking about:
What they sent me IS a Schneider breaker and it IS clearly marked 250 v.
No need to speculate further.
Circuit Breaker 2P 250V 16A Low-voltage DC Miniature Circuit Breaker For Solar Panels Grid System Din Rail Mount - - Amazon.com
Circuit Breaker 2P 250V 16A Low-voltage DC Miniature Circuit Breaker For Solar Panels Grid System Din Rail Mount - - Amazon.com
www.amazon.com
What they sent me IS a Schneider breaker and it IS clearly marked 250 v.
No need to speculate further.
