February 16, 20197 yr 1 minute ago, The Terrible Triplett said: Why is that? NoArk Breaker is rated at 40amp, and it is panel side. It's not about the current rating, it's about physically fitting the cable into the breaker. Normal 6-16kA DIN breakers usually can fit max 16mm and then it's still a tight fit. Also, looking at that clamping tech on the breaker up close would lead me to believe that I have to check my terminations quite often.
February 16, 20197 yr 9 minutes ago, The Terrible Triplett said: Why is that? NoArk Breaker is rated at 40amp, and it is panel side. But you got me to doubt myself, so I checked again: 25mm2 from MPPT to Inverter - I connected MPPT direct to battery points in Inverter. And 16mm2 from combiner box to MPPT. Sorry @VisN mind got stuck on the 25mm2 cable I crimped last. TTT, Thank you anyway. I've always wondered how people use thicker cable and circuit breakers which seem to only take smaller gauge cable.
February 16, 20197 yr 2 minutes ago, anotherbrownbear said: 16mm and then it's still a tight fit Sorry that was my bad ... but it went in easily, that I know. 8 minutes ago, anotherbrownbear said: Also, looking at that clamping tech on the breaker up close would lead me to believe that I have to check my terminations quite often. Me, I believe we must check every connections over the entire system regularly - at least every couple of months. Way I look at it there is some heat involved on all the connectors, when system works hard then not, and heat and cooling has an effect on everything.
February 16, 20197 yr The cables actually move when carrying current, or I should rather say vibrate. This is what causes some terminals to loosen over time. With the correct clamping tech, they stay put. The trick is, to make the clamp almost seize up when getting the the right torque value. So that you have to put some effort into loosening it. Most manufacturers haven't managed to get that bit right.
February 16, 20197 yr I've been watching this with some interest. I have 25mm^2 going into Gewiss breakers. Getting them into the breaker was actually easy. Getting them into the distribution block wasn't!
February 16, 20197 yr So which DC breakers are people using between battery bank and inverter and how are they accommodating larger cable? Victron recommend 35mm for runs between 0-5m for my inverter, could I go 25mm if my run is eg. 2m? Edited February 16, 20197 yr by VisN
February 16, 20197 yr 34 minutes ago, VisN said: So which DC breakers are people using between battery bank and inverter and how are they accommodating larger cable? Fused disconnects. They have an M8 bolt, so you crimp a lug on and bolt it down, that's how you accommodate it. You get breakers with bolted connections too... but of course they are not cheap. Edited February 16, 20197 yr by plonkster typos
February 16, 20197 yr 49 minutes ago, plonkster said: I've been watching this with some interest. I have 25mm^2 going into Gewiss breakers. Getting them into the breaker was actually easy. Did you use pin plugs for the breaker?
February 16, 20197 yr 37 minutes ago, VisN said: So which DC breakers are people using between battery bank and inverter and how are they accommodating larger cable? Victron recommend 35mm for runs between 0-5m for my inverter, could I go 25mm if my run is eg. 2m? https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.rpc.com.au/pdf/ABB_miniature_circuit_breaker_s800PV.pdf&ved=2ahUKEwiYsrCQhsDgAhX3XhUIHc1mDC4QFjAKegQIAxAB&usg=AOvVaw0ZbeDK_Fj7ATWnNubZVK0k This or similar size breakers. Or like @plonkstersaid, pull fuse disconnects or you can use rotary fuse disconnects as well.
February 16, 20197 yr 3 minutes ago, anotherbrownbear said: Did you use pin plugs for the breaker? You mean bootlaces? Nope... just torqued them down hard. I hear in Australia it is now pretty much regulation that you have to crimp bootlaces on. I might well redo it soon.
February 16, 20197 yr 4 minutes ago, plonkster said: You mean bootlaces? Nope... just torqued them down hard. I hear in Australia it is now pretty much regulation that you have to crimp bootlaces on. I might well redo it soon. Gees, do you need a job in our workshop? Can use those magic hands to get the big cables in small holes. Hahaha. Bootlace poses different problems when you try and get it in small spaces. Sometimes the square shape makes it harder to fit in. So we use pin lugs instead.
February 16, 20197 yr 1 minute ago, anotherbrownbear said: So we use pin lugs instead. I get all my training on the interwebz... thanks for this!
February 16, 20197 yr 18 minutes ago, anotherbrownbear said: https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.rpc.com.au/pdf/ABB_miniature_circuit_breaker_s800PV.pdf&ved=2ahUKEwiYsrCQhsDgAhX3XhUIHc1mDC4QFjAKegQIAxAB&usg=AOvVaw0ZbeDK_Fj7ATWnNubZVK0k This or similar size breakers. Or like @plonkstersaid, pull fuse disconnects or you can use rotary fuse disconnects as well. Gulp!!!
February 16, 20197 yr 12 minutes ago, VisN said: Gulp!!! Amen to that! I used Brad Harrison connectors like so:
February 16, 20197 yr 23 minutes ago, VisN said: Gulp!!! Yeah but that's RS Components. Real price is more or less half of that
February 16, 20197 yr 10 minutes ago, The Terrible Triplett said: Amen to that! I used Brad Harrison connectors like so: That's not a disconnector. In other words, it is not rated to be disconnected under load.
February 16, 20197 yr 21 minutes ago, VisN said: Gulp!!! Well... it is ABB (so that usually means 300% of the other guys), and it is RS Components (they import via some other channel from the UK, if you buy from an ABB distributor here you should get it between 20% and 80% cheaper). I like ABB... I like them a LOT... and it is really really good quality... but man they are expensive, so you really have to shop around a bit. They were the only guys who stocked the expensive RCD I needed last year though... so ek het maar betaal. For comparison... sure, it's a tad lower on the voltage end, but certainly workable. And this is from Sonop... also not the cheapest place.
February 16, 20197 yr 3 minutes ago, anotherbrownbear said: That's not a disconnector. In other words, it is not rated to be disconnected under load. You must at least have a good fuse with those things... I'd hate having to pull those apart in an emergency. Even the Mersen one I advised... man pulling that thing under load makes a nice big arc.
February 16, 20197 yr 8 minutes ago, plonkster said: I'd like to see how they get to that 6ka rating on that voltage. If you compare the 800VDC from ABB it is 1.6ka for the disconnect and 5ka for the breaker. If you compare the other breakers in the family, they are 36ka for 690vac and 440vdc.
February 16, 20197 yr 2 minutes ago, anotherbrownbear said: I'd like to see how they get to that 6ka rating on that voltage. If you compare the 800VDC from ABB it is 1.6ka for the disconnect and 5ka for the breaker. If you compare the other breakers in the family, they are 36ka for 690vac and 440vdc. Right. That's what I noticed with ABB stuff... generally the extra money you pay does buy better quality. For example, I bought two ABB RCDs during my nuisance tripping hunt, and both of them were rated for more than double the mechanical trips of the Hager breakers I sometimes use. I expect the same recipe extendes downwards. Still... there is a pain threshold around 4k... at least or me 🙂
February 16, 20197 yr 27 minutes ago, plonkster said: You must at least have a good fuse with those things... I'd hate having to pull those apart in an emergency. Even the Mersen one I advised... man pulling that thing under load makes a nice big arc. Do have a fuse and when you connect / disconnect them, their is no chance that you can be shocked. Been there tried that. The key here is that the batteries are on wheels ... useless to have a disconnect that is still wired in. 😉 Ie. at this point the pins are not touching yet completely closed. Even get nice handles: 34 minutes ago, plonkster said: also not the cheapest place Their prices seem to go up and up - they are supposed to be INCL about R230 - R250.
February 16, 20197 yr 11 minutes ago, The Terrible Triplett said: at this point the pins are not touching yet completely closed. There will be a definite arc when this is opended or closed under load. Even though it is on a trolley, the correct way of doing it is to add a disconnect on the trolley and then wire it to the plug. That way you can still move it around but be safe when connecting and disconnecting it if need be under emergency conditions.
February 16, 20197 yr Just now, anotherbrownbear said: ... definite arc ... O yes, I hear the arc when I connect the batts to the inverter, when the caps draw power. Am just not sure it is a problem. A old toppie once told me, less is better. So I try and keep the minimum amount of things on the wires. It works as follows: Switch off inverter / panels then connect / disconnect the batts. That is the law for all of us. If inverter is say busy burning and it is still under load, who gives a damn that then that there is an ark when disconnecting the batts to move them away - if you can. 🙂 My hands will not be burned ... did it on a UPS accidentally before. Huge ark inside, that is where I go the idea. Also see the 4X4 / caravaners use them a lot. They are 12v versus my 24v. What am I missing?
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