48v 400amp ANL fuse holder?
- Thread starter Fraser
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This 80v 400 amp fuse from Victron may be designed to work in their Lynx system. But also on that page is a link to a Victron fuse holder.
Thank you! that helps because that site also had a data sheet. A lot of the ones I found said they are 32v. The one you found says 80vdc which is great and I have seen that fuse holder here in uk. So I now know that’s fine. Surely the fuse is the bit that matters the holder should be able to take the volts? I already ordered that fuse but didn’t order that holder because it didn’t have a cover. I ordered another holder and I’m hoping that will be fine or I just send it back get the one you found and see if I can get some sort of cover for it. Thanks for the help.
Fraser
It may be able to but I haven’t found anything definite. The other problem with the lynx system is that I read the power in can only take a 22 mm cable where the fuses go. That isn’t big enough to take my inverter cable 50mm . So I’m attaching it to the bus bars at the ends that stick out and having a separate fuse and holder in the cable.
I haven't seen any formal write up, but anything that says it's rated for 48v may not be acceptable for a 16s battery system. The charge voltage can get up to 58 volts, which exceeds the 48 volt rating enough to be a concern. I think it's Blue Sea Systems that is going to make a change to their ratings such that an item rated for 48 volts now would only be rated for 32v or something like that so that it's clear it shouldn't be used in a 48 volt system.
Gadgetnerd
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I had a similar question and searched 60V breakers online for my16s lifepo4 system. They do exist but my local solar supplier assured me they've been using these 48v rated DC breakers for years. Granted lead acid banks might only run about 52 volts but still...having said that the most important thing is that it's a dc breaker,(completely diff from ac) second that the amperage matches the maximum inverter draw and is 25% over the conductor rating, thirdly is voltage. Also a lot of dc breakers I saw online are rated 0-150vdc.
Hedges
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I doubt the plastic of a fuse holder would break down at 80V vs. 48V. Difference is likely covers to keep fingers off the conductors, for safety reasons.
As you say, the fuse is was matters as far as performance vs. voltage.
DC breakers - and then there is polarity. If polarized, when breaking at full load, or dead-short overload, they only function if current is going the right direction.
Both fuses and breakers, AIC rating. That's going to matter more at higher voltages and with Lithium Batteries. So I'm using class T.
Nerd Penguin - I think you're mixing up a couple. Breaker amperage should be 25% over inverter draw, but not over conductor rating.
I suggest considerably more than inverter rating (and then conductor sufficient to fit this higher rating.)
Running at 100% rated output the inverter will be at some lower efficiency, so drawing more watts. Battery approaching low-voltage disconnect, so more amps to deliver those watts. Current draw from battery won't be DC, it will have a high ripple current on it, possibly swinging almost zero to 2x average. Those current pulses have a higher RMS than DC would have, which heats breaker more.
As you say, the fuse is was matters as far as performance vs. voltage.
DC breakers - and then there is polarity. If polarized, when breaking at full load, or dead-short overload, they only function if current is going the right direction.
Both fuses and breakers, AIC rating. That's going to matter more at higher voltages and with Lithium Batteries. So I'm using class T.
Nerd Penguin - I think you're mixing up a couple. Breaker amperage should be 25% over inverter draw, but not over conductor rating.
I suggest considerably more than inverter rating (and then conductor sufficient to fit this higher rating.)
Running at 100% rated output the inverter will be at some lower efficiency, so drawing more watts. Battery approaching low-voltage disconnect, so more amps to deliver those watts. Current draw from battery won't be DC, it will have a high ripple current on it, possibly swinging almost zero to 2x average. Those current pulses have a higher RMS than DC would have, which heats breaker more.
Gadgetnerd
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Next is the 125% requirement in 210.19(A)(1) and 215.2(A)(1): “The minimum feeder circuit conductor size,before the application of any adjustment or correction factor,shall have an allowable ampacity not less than the noncontinuous loads plus 125 percent of the continuous loads” (emphasis added). This requirement ensures that conductors and overcurrent devices are not operated continuously at over 80% of rating
Gadgetnerd
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There are multiple exceptions under 240.3(a-g) where OCPDs can exceed the ampacity of the conductors. <800amps, motor loads, hazard circuitry, etc. I have an air conditioner and a fridge....motor loads.
Hedges
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Do you have any examples of where someone should use a fuse on inverter battery cable, and cable with ampacity is less than fuse rating?
How about fuses and wires for PV strings?
How about AC wiring from inverter to breaker panel, or breaker panel to household loads?
A fuse would have to carry motor starting surge, typically I see 5x nameplate current. There are dual-element fuses providing fast blow at high current and slow blow for moderate overload.
I see a list for 240.3, but haven't been able to find/follow the details and understand how NEC could allow a wire to be fused such that the load (maybe an overloaded motor) could draw over 100% of ampacity continuously. Seems to me the underlying requirement of OCP is that wires are not heated in excess of their insulation rating. I the case of moderate overload, they are for a period of time, but then the protection trips. I understand wire ampacity and OCP are designed such that about 100 such overloads can be withstood before the wire insulation has baked out and goes bad. The requirement of max 15A OCP for 14 awg (20A ampacity), 20A for 12 awg (30A ampacity), and 30A for 10 awg (40A ampacity) means that those circuits could tolerate far more or perhaps unlimited overloads. Good for household convenience outlets that consumers are likely to plug too much into.
For my branch circuits (e.g. lighting, air conditioner, laundry, arc welder) the ampacity of the wires in a cable is always at least as much as the breaker rating. The breakers are thermal-magnetic and will trip instantly at 5x their rating, varying time delay below that, which takes care of motor starting.
The arc welder is a bit interesting. 240V input and 50A breaker. Output is up to 240A, 80Vrms open circuit. Transformer is 3:1 step-down, so 240A output is drawing 80A through the 50A breaker. Duty cycle is something like 1 minute welding to 10 minutes cooling off, and breakers will carry 150% of their rating for around 10 minutes. I think the breaker would help protect the welder from overheating if operated too long. It doesn't have any thermal shutdown.
Yeah I have added a 48v isolation switch between my power inns. Now this is where it gets tricky and I’m going to ask this question which is similar to yours somewhere else on this forum.
when I bought the pylontech us3000 c batteries they say you don’t have to have a isolation switch because you can turn them off, but some installers want more safety. And if so...... to isolate both positive and negative? So is that somehow to compensate in some way not having enough voltage stopping power? I’m just not knowing enough to know the reasons. But they only sold along side the pylontech battteries these 48v isolation switches even though they are 56-58 v. Like you say. Bit of a worry glad I can turn mine off also.
I know this thread is pretty old .. but those information can be of use, i'm using ANl fuse for my main battery bank, i got a 48V system with a 5.5kW inverter plus a 48V circuit in parrallel.
My max amp going through the battery wire should be something like 150A. My wire is 50mm2, 1.5m and should be able to handle 200A.
The idea here is that i can't put a 150A ANL fuse
Check Page 2 and 3 : https://www.renogy.com/content/files/Manuals/ANL-Fuse.pdf
Let's say i use a 80A fuse, it will trip at
250A - 1s
160A - 10s
140A - 100s
120A - 1000s (ok this one not on the graph... just guessed it)
If i want my fuse to blow in under 10s at 150A, i need a 80A fuse, not a 150A one.
It will also mean that i can not stay at 120A for more then 1000s.
And, as you can see here : https://www.bluesea.com/support/articles/Circuit_Protection/95/Choosing_Circuit_Protection
Their blow timing are different .. meaning ... it's pretty hard to guess when an ANL will blow if you do not have the specific graph for your particular ANL fuse. What i mean by that ... do not use a fuse if you do not have the datasheet coming with it.
My max amp going through the battery wire should be something like 150A. My wire is 50mm2, 1.5m and should be able to handle 200A.
The idea here is that i can't put a 150A ANL fuse
Check Page 2 and 3 : https://www.renogy.com/content/files/Manuals/ANL-Fuse.pdf
Let's say i use a 80A fuse, it will trip at
250A - 1s
160A - 10s
140A - 100s
120A - 1000s (ok this one not on the graph... just guessed it)
If i want my fuse to blow in under 10s at 150A, i need a 80A fuse, not a 150A one.
It will also mean that i can not stay at 120A for more then 1000s.
And, as you can see here : https://www.bluesea.com/support/articles/Circuit_Protection/95/Choosing_Circuit_Protection
Their blow timing are different .. meaning ... it's pretty hard to guess when an ANL will blow if you do not have the specific graph for your particular ANL fuse. What i mean by that ... do not use a fuse if you do not have the datasheet coming with it.
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Hedges
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Why do you need it to blow in just 10 seconds at 150A?
I don't think thermal fuses or breakers can reliably hit short trip times at modest currents. They can do so fast enough to avoid overheating wires.
Magnetic trip or electronic trip might work for such controlled times.
Thermal OCP, breakers at least, seem to age and trip at lower current later. Extra margin in rating could avoid nuisance trips.
Loads don't necessarily draw a DC current or AC sine wave, so have higher RMS than the delivered power would suggest.
To be honest ... i decided myself that 10s under overload is not normal .. so .. the circuit should be opened, all my devices should not draw more then 150A... and even that amount will likely never met. If it ever goes over 150A .. then something is wrong .. better cut the circuit, the faster the better. Now i've chosen 10s cause it also give me 1000s at 120A (120A which would eventually be met in real use, but not for 1000s, just burst for some secs).
By electronic controlled, you mean something like a shunt that would open the circuit instantly when parameters are met (like 10s over a chosen max Amp ?)
Hedges
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Yes, I meant a remote-trip circuit breaker controlled by a measurement circuit.
Most common for large breakers.
I've tested a few thermal-magnetic QO breakers. At 50% overload, 10 minutes or so. Or fast trip at about 5x rated current.
I've been contemplating magnetic/hydraulic breakers lately (Midnight sells some, but I want other values.)
I think those will give the trip times you want. Most are about 1 second for modest overload.
Most common for large breakers.
I've tested a few thermal-magnetic QO breakers. At 50% overload, 10 minutes or so. Or fast trip at about 5x rated current.
I've been contemplating magnetic/hydraulic breakers lately (Midnight sells some, but I want other values.)
I think those will give the trip times you want. Most are about 1 second for modest overload.
Interesting, they are pretty fast... !
I'm looking into knife breaker right now, most of them are not expensive and some are pretty fast... !
The question arise about electronic, is it smart to use an electronic fuse which can fail (failing at detecting an anormal current) vs a fuse which will melt.
Cause i could make one easily, i already planned to connect an arduino to my shunt, i could just monitor the current and cut the circuit if it met some "rules". And it can react under a second (nearly that) BUT i would still need a "mecanical" fuse, cause this arduino thing would be "complex" and prone to fail (by that i mean not being able to detect the problem).
Ho and i competly forgot, my BMS got a Short Current Protection security and a Short Curent Protection time setting... not sure what it is, i suppose it's the maximum time the BMS would stay on with this "short" (dunno how it detect the short, maybe when it's over Peak Discharge witch is 300A) before disconnecting ... but ... i can't imagine the bms to sustain a fast increase of current. I dunno.
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