Yup, they cost quite a bit more. That's why I thought this one was AC based on the price. I got the one I used because it's 2/3 the size of the $6 breaker, but then found out it was DC when it started tripping. I'm replacing it with the 50A version, assuming that it will do 60A, which is enough for my riding.
Circuit breaker blew like a fuse
- Thread starter Zambam
- Start date
It's both AC and DC, 277VAC 50/60Hz or 80VDC, 50A. The one that's in place right now is 277VAC 50/60Hz or 80VDC, 40A
I don't know what the different types of mini circuit breakers are. Found this site which gives a good explanation.
uk.rs-online.com
I did a spark test using a 10 A automotive fuse to connect the 60V battery. It sparked loudly but the fuse did not blow. Good sign!
MCB (Miniature Circuit Breakers) Guide | RS
This MCB buying guide explains everything you need to know about the types and sizes available, the best brands, and where to use miniature circuit breakers.
I did a spark test using a 10 A automotive fuse to connect the 60V battery. It sparked loudly but the fuse did not blow. Good sign!
I believe in the context of how "MCB" is used earlier in this thread, it would be a magnetic circuit breaker (not mini). There a two common type of breakers, magnetic and thermal. Magnetic provide instantaneous tripping under high current spikes, while thermal is slow acting and trips when a high current flows over a period of time. The third common type, and what you see most of the time in you house, etc., is thermal magnetic, which provides both types of protection, instantaneous as well as slow acting tripping, depending on the condition.I don't know what the different types of mini circuit breakers are. Found this site which gives a good explanation.
MCB (Miniature Circuit Breakers) Guide | RS
This MCB buying guide explains everything you need to know about the types and sizes available, the best brands, and where to use miniature circuit breakers.
I did a spark test using a 10 A automotive fuse to connect the 60V battery. It sparked loudly but the fuse did not blow. Good sign!
What do you think of this thermal magnetic MCB https://www.digikey.com/en/products/detail/asi-ez/NDB2-63D4-1/15670985 $11.20 from DigiKey?
JackofHearts
1 mW
I piggyback on this post because it is related to my issue. I always try not to start a new post.
I have a scooter in Asia. I built a 72v 60ah lithim-ion battery with Daly BMS to replace the 20ah sealed lead acid batteries. I wanted to extend the distance.
With the new battery, the 40A MCB trips when I give sudden throttle to go over a hump in the road. If I start slowly on flat ground, it doesn't trip, but even on flat ground if I increase the speed suddenly, it trips.
Question is: Controllers state a AMP range on them which I think is output. My controller is run-of-the-mill from China and I suspect it has around 25AMP output - this is based on some of the searches I've done on 72v controllers. If AMPs coming into the controller are 50 how does controller output around 25?
Both new and old batteries are 72v - the controller should pull same AMPs from 20ah battery as the 60Ah battery so why the MCB keeps tripping is beyond me?
Wire from battery to controller is labeled 2.5mm squared. That isn't very thick, but if that wire handles 72v 20Ah I think it should handle 72v 60Ah.
The MCB is for a fault so I keep thinking about carefully trying to connect battery to controller without the MCB, but I'm not sure how the controller handles large AMPs in while outputting smaller amount to current to the motor.
I have a scooter in Asia. I built a 72v 60ah lithim-ion battery with Daly BMS to replace the 20ah sealed lead acid batteries. I wanted to extend the distance.
With the new battery, the 40A MCB trips when I give sudden throttle to go over a hump in the road. If I start slowly on flat ground, it doesn't trip, but even on flat ground if I increase the speed suddenly, it trips.
Question is: Controllers state a AMP range on them which I think is output. My controller is run-of-the-mill from China and I suspect it has around 25AMP output - this is based on some of the searches I've done on 72v controllers. If AMPs coming into the controller are 50 how does controller output around 25?
Both new and old batteries are 72v - the controller should pull same AMPs from 20ah battery as the 60Ah battery so why the MCB keeps tripping is beyond me?
Wire from battery to controller is labeled 2.5mm squared. That isn't very thick, but if that wire handles 72v 20Ah I think it should handle 72v 60Ah.
The MCB is for a fault so I keep thinking about carefully trying to connect battery to controller without the MCB, but I'm not sure how the controller handles large AMPs in while outputting smaller amount to current to the motor.
It shouldn’t trip, obviously, and there is a fault.
But the fault is as likely to be the fault detector as anything else.
Plus, for our purposes with highish DC voltages there’ll be arcing and resultant contact damage every time they trip, that will get progressively worse.
For that reason, I treat them like a disposable fuse. One trip and they belong in the bin.
So, I’d just replace it. Not on the assumption that it’s throwing false positives, just on the grounds that it’s a simple inexpensive trouble-shooting step that has the upside of not being wasteful if proven ineffective i.e. you end up with two functional breakers (one spare) and still have the same problem to solve.
Use a “C” or similar breaking curve. You don’t want a trigger happy MCB in this application.
You’re rightfully concerned that it might be behaving legitimately in response to a genuine fault, however MCBs can fail, like anything else. No need to be suspicious about the battery or controller at this point.
They’re pretty damn reliable though. The only one I I ever had to replace out of necessity was on a dedicated oven circuit that began to trip. The gutter above the switchboard had been leaking on to it for a decade or more. The MCB was thoroughly rusted inside, to the point it was surprising it stood up for half as long as it did.
It’s not happening quite the way you think. Someone else will explain it for you though, I’m late for dinner.
Did the system have any problems before replacing the battery?
Is the breaker part of the system, or part of the new battery?
If it's part of the new battery and is rated properly for the battery/BMS/wiring, your system is drawing more current than the battery is capable of, so you'll need a different battery that can supply more current than the system needs, instead of the one you have.
Do you have a wattmeter or anything in your system that displays or logs the amps or watts being drawn from the battery? If not, it would be helpful to at least borrow a clamp-on ammeter to measure the peak current your system draws in normal operation and at this trip point.
Breakers don't trip instantly at their rating, they trip well above it if it's tripping "instantly" rather than after a sustained time of that load. So either the breaker is defective, mislabelled, or the system is drawing a lot more current than the 40A breaker rating.
Without knowing what the actual current draw is, you won't know if you have properly rated stuff in the system (wiring, connections, breaker, battery, BMS, etc). (when troubleshooting this kind of problem it's not really safe to just go by the labels on things and assume currents will only be as high as they list, testing is needed to be sure).
What the amp rating on the controller means depends on the specific controller's design. Most of them list a battery current limit, and if they don't state otherwise this is probably what it refers to, so this would be input current.
If they list a phase current, or both phase and battery, the one you care about for this problem is only battery current.
Anyway, you can't just assume there's a specific amount of current based on other controllers. You must check *your actual* controller's ratings. If they are not on the label, and there aren't any markings on it to tell you, you would have to do the test with a meter to find out what it is, or else you can't reliably fix the problem you have.
Output (phase) current can be much higher than input (battery) current, because controllers are power converters--they take a voltage and current at the input and make a different voltage and current waveform on the output to make the motor do what you command via the control inputs. (if you need details on how this works, there are a few threads you can look up around here on how motor controllers work; it gets a bit complicated so is beyond the scope of this thread).
If the old batteries sagged in voltage under the same load, you might not have gotten this amount of current, because the controller may ramp down it's current draw as voltage drops to prevent overload of the battery (some do this, some don't). If the new battery doesn't sag in voltage under this load, the controller would then draw more current because it doesn't see a voltage drop and thus no reason to decrease current draw.
Ah has nothing to do with current, it is only capacity, so it has nothing to do with what the wire has to handle. A and Ah look similar because they both have an A in them, but mean completely different things.
If you remove the breaker, then whatever is causing hte overcurrent it is protecting against may damage the parts not able to handle the overcurrent (this is why the breaker is there). (assuming it's not just a faulty breaker).
Since you don't yet know there isn't a fault it's protecting against, it's not really safe to wire around it.
Maybe your Lithium battery has lower internal resistance than the Lead Acid, delivering more current, tripping the breaker? You can try measuring the amp draw with a clamp on ammeter and see if that's the case and may need to go with a higher amp MCB.
If your scooter has dual batteries you can get the 1P-1P dual power MCB from 6 A up to 150 A. https://www.aliexpress.us/item/3256803152158946.html?spm It has a common on one side of 2 breakers with an interlock that allows only one breaker to be on at a given time.
I am still using the other (good) leg of the 1P-1P MCB since I have just a single lead acid battery. So far the it has not tripped again. I carry a heavy duty alligator clip lead to jump it in the event it does trip and blow.
JackofHearts
1 mW
Writing a book here so you guys have all you need for suggestions.
I took a break and then got back at it. Since the new battery is a bit further away from the old, I changed the wires, I have 8 gauge stranded wire on it now which is good for 40AMPs easily. I think it will handle 50AMPs for quite a while before melting. I feel the wire is beyond what's needed especially for short tests. The new 8 gauge wires go to the MCB, but on the other side of the MCB the 2.5mm wires are still there because they go into the controller - I don't want to change them out. I upgraded to 8 gauge only because the new lithium battery is a tiny bit further away from the controller than the LA batteries. I crimped and soldered good ring terminals on the 8 gauge wire.
2.5mm wire is rated for just around 13 to 14 AMPs though can handle up to 25AMP for a short time. When using the LA battery, those wires most likely to experience 25AMP when taking off from a stop but then level off as I ride the flat road. Based on those wires, it seems the motor/controller will normally pull less than 14AMP most of the time. How a 40AMP MCB is tripping is beyond me at this point.
I've built a bunch of batteries for my solar. I use high end BMSs on them. This battery I built for the scooter has a 100AMP Daly BMS with bluetooth so I'm able to set overcurrent. Because of those 2.5mm wires that I mentioned, I had and still have it set to just 30AMPs which is high for 2.5mm wires but I thought it would be a good starting point. The BMS isn't shutting down - the MCB trips much too fast.
This post here is pretty much same issue I'm having - shame the OP didn't post a solution:
endless-sphere.com
A picture from the above post is like what I have with regard to the 2.5mm wires. The wires I have on the old battery even has those red and black caps to cover the terminal screw. Those blue wires coming off the battery at the bottom on the picture look much thicker than the ones series connecting the battery but the thicker blue wires don't do much - the other wires would still be a weak link.
A 40AMP circuit breaker should take a spike quite easily is my thinking since they are designed to trip far above what they are rated. It really shouldn't trip with just a little bit of throttle. Keep in mind, when I revert back to the LA battery, the CB doesn't trip. CB only trips when the lithium battery is connected.
My next step as all have suggested is to measure AMPs when old battery vs. new battery are connected. I have a DC clamp-on meter.
My new lithium-ion battery is 17s and fully charged is 17*4.20=71.4 volts. The last I checked it was charged to around 70v so not much, if any, different than the LA battery (5 in series ... 13.6-14.4v range ... 14.4 * 5 = 72).
The new lithium battery can output 60AMPs continuous but AMP output from either battery shouldn't matter given the controller/motor will only pulls what's needed. Only concern is when there isn't enough battery to handle the load, having more than enough AMPs is fine.
A lot of the above is just me thinking out loud and giving some additional information.
Another next step: I will order another MCB.
The current MCB is rated at 72v/40AMPs - what do you suggest I replace it with?
I took a break and then got back at it. Since the new battery is a bit further away from the old, I changed the wires, I have 8 gauge stranded wire on it now which is good for 40AMPs easily. I think it will handle 50AMPs for quite a while before melting. I feel the wire is beyond what's needed especially for short tests. The new 8 gauge wires go to the MCB, but on the other side of the MCB the 2.5mm wires are still there because they go into the controller - I don't want to change them out. I upgraded to 8 gauge only because the new lithium battery is a tiny bit further away from the controller than the LA batteries. I crimped and soldered good ring terminals on the 8 gauge wire.
2.5mm wire is rated for just around 13 to 14 AMPs though can handle up to 25AMP for a short time. When using the LA battery, those wires most likely to experience 25AMP when taking off from a stop but then level off as I ride the flat road. Based on those wires, it seems the motor/controller will normally pull less than 14AMP most of the time. How a 40AMP MCB is tripping is beyond me at this point.
I've built a bunch of batteries for my solar. I use high end BMSs on them. This battery I built for the scooter has a 100AMP Daly BMS with bluetooth so I'm able to set overcurrent. Because of those 2.5mm wires that I mentioned, I had and still have it set to just 30AMPs which is high for 2.5mm wires but I thought it would be a good starting point. The BMS isn't shutting down - the MCB trips much too fast.
This post here is pretty much same issue I'm having - shame the OP didn't post a solution:
Did I kill my 60v controller with a new 60v 150Ah lithium battery?
I have a three wheeled chinese electric foodtruck - like a Piaggio Ape. I was excited to upgrade range by adding a 60v 150AH Lithium battery pack from 60V lead acid. Custom made by Smart Propel but based on this 100Ah version. Charged the pack and installed it. It charged up to 73v. Managed to...
endless-sphere.com
A picture from the above post is like what I have with regard to the 2.5mm wires. The wires I have on the old battery even has those red and black caps to cover the terminal screw. Those blue wires coming off the battery at the bottom on the picture look much thicker than the ones series connecting the battery but the thicker blue wires don't do much - the other wires would still be a weak link.
A 40AMP circuit breaker should take a spike quite easily is my thinking since they are designed to trip far above what they are rated. It really shouldn't trip with just a little bit of throttle. Keep in mind, when I revert back to the LA battery, the CB doesn't trip. CB only trips when the lithium battery is connected.
My next step as all have suggested is to measure AMPs when old battery vs. new battery are connected. I have a DC clamp-on meter.
My new lithium-ion battery is 17s and fully charged is 17*4.20=71.4 volts. The last I checked it was charged to around 70v so not much, if any, different than the LA battery (5 in series ... 13.6-14.4v range ... 14.4 * 5 = 72).
The new lithium battery can output 60AMPs continuous but AMP output from either battery shouldn't matter given the controller/motor will only pulls what's needed. Only concern is when there isn't enough battery to handle the load, having more than enough AMPs is fine.
A lot of the above is just me thinking out loud and giving some additional information.
Another next step: I will order another MCB.
The current MCB is rated at 72v/40AMPs - what do you suggest I replace it with?
JackofHearts
1 mW
I'm waiting on the new MCB to arrive, but I have a question about going without a MCB at least as an experiment.
For those just reading this, my MCB keeps tripping when using a 72v lithium-ion battery rather than the 72v LA batteries that came with my scooter.
Based on the stock wiring, I think my controller is a 20AMP controller at the most. If 20AMP ... maybe 30AMP peak, other than spikes like when pulling off from a stop or going up a hill, it shouldn't exceed 20AMPs very often. The controller can only pull what it's rated. So if I carefully connect the new battery 72v battery without a MCB, the only thing at risk are the wires overheating. I'm in the Philippines... no hills around me.
I'm thinking about connecting the new battery without a MCB just for a short 5 minute ride then feel the wire for heat.
I always second guess myself no matter how much I know about electricity so just floating this idea. What's the worst that can happen? It is just a 630 dollar scooter. I don't think it will go up in flames in just 5 minutes.
For those just reading this, my MCB keeps tripping when using a 72v lithium-ion battery rather than the 72v LA batteries that came with my scooter.
Based on the stock wiring, I think my controller is a 20AMP controller at the most. If 20AMP ... maybe 30AMP peak, other than spikes like when pulling off from a stop or going up a hill, it shouldn't exceed 20AMPs very often. The controller can only pull what it's rated. So if I carefully connect the new battery 72v battery without a MCB, the only thing at risk are the wires overheating. I'm in the Philippines... no hills around me.
I'm thinking about connecting the new battery without a MCB just for a short 5 minute ride then feel the wire for heat.
I always second guess myself no matter how much I know about electricity so just floating this idea. What's the worst that can happen? It is just a 630 dollar scooter. I don't think it will go up in flames in just 5 minutes.
This is different to house wiring. It’s not melting wires you need to worry about, it’s dead shorts.
Your BMS and Controller PCBs can be crammed, with little separation between power traces, such that a rolling blob of solder could wedge between them.
However, the primary cause of shorts will be you poking around with a flat head screwdriver, crossing wires that the insulation could melt on, or going “I wonder what happens when I plug this black wire into this other red one”.
If you think you can avoid these sort of situations, you don’t need fusing, you need a reality check.
Everyone has momentary lapses of reason. And when you do, the firecracker spark and bang is a great wake up that you’re an idiot - partly for what you just did, but mostly for being cocky enough to think you wouldn’t do it and foregoing the fuse.
(If you need a reminder of the destructive energy of high current shorts, get the the jumper leads hooked onto the car battery and tap them together).
Only an idiot believes they’re not an idiot. I’m sure of that, although not so much about whether the reverse applies, in that believing you’re an idiot is a fair indication that you’re not one.
Fuses make you feel clever. You do something stupid. They go pop. And then you get to feel clever (for installing the fuse) despite just having done something very stupid.
As a stupid person, I can’t recommend them enough.
Your BMS and Controller PCBs can be crammed, with little separation between power traces, such that a rolling blob of solder could wedge between them.
However, the primary cause of shorts will be you poking around with a flat head screwdriver, crossing wires that the insulation could melt on, or going “I wonder what happens when I plug this black wire into this other red one”.
If you think you can avoid these sort of situations, you don’t need fusing, you need a reality check.
Everyone has momentary lapses of reason. And when you do, the firecracker spark and bang is a great wake up that you’re an idiot - partly for what you just did, but mostly for being cocky enough to think you wouldn’t do it and foregoing the fuse.
(If you need a reminder of the destructive energy of high current shorts, get the the jumper leads hooked onto the car battery and tap them together).
Only an idiot believes they’re not an idiot. I’m sure of that, although not so much about whether the reverse applies, in that believing you’re an idiot is a fair indication that you’re not one.
Fuses make you feel clever. You do something stupid. They go pop. And then you get to feel clever (for installing the fuse) despite just having done something very stupid.
As a stupid person, I can’t recommend them enough.
JackofHearts
1 mW
But sir, bare with me, please, the LA battery doesn't trip the MCB ... the lithium-ion battery does ... I simply disconnect one and connect the other. There is no short in the system .. if there was a short, the LA battery would experience it too. When the lithium battery is connected and the scooter is sitting idle, nothing happens, no MCB tripping, if there was a short, the moment I flip on the MCB it would trip. When I give it a little throttle, how would that creat a short with the lithium battery but not the LA battery?
There is nothing wrong with the lithium battery because I used it as a matter of curiosity in a 3 wheeled electric trike that my wife drives.
I have really thick skin so it's okay to insult me. I can take it. Call me every name you can think of and it just goes in one ear and out the other - I feel no pain and experience no emotion over it. So if you reply again, please, along with an answer/opinion that focuses directly on the questions I've asked, include as many insults as you deem neccessary please try to provide a thoughtful answer/opinion. Your answer above is not thoughtful, sir.
Sorry, I meant no offence.
I made a case against your proposal to remove the breaker.
It’s probably faulty (giving false positives), but you cannot verify that.
The new battery could be at fault, or eliciting a pre-existing system fault that the old battery did not.
So, at this juncture …
Ordering a replacement breaker is sound.
Busting out the clamp meter is sound.
Removing the breaker is unsound.
If you’re getting impatient for the new part to arrive, a 40A fuse from a car shop would tide you over.
You asked what’s a recommended replacement for the 40A breaker. Sounds like you’ve already ordered one, but for the power levels you’re proposing, 40A sounds fine. Or 30 or 60 or 80. As long as it’s higher than your average current draw, and assuming it’s not getting cooked by butting up against a hot controller, it’ll be fine.
I repeat, in this application the role of the breaker is not to protect wiring, as with houses, it’s to protect electronics.
People overload house circuits by plugging too much stuff in. This does not apply to electric vehicles. You size the wire according to your needs. If it’s undersized for the current that your controller draws, the only valid solutions are either reducing the current or beefing up the wiring.
I made a case against your proposal to remove the breaker.
It’s probably faulty (giving false positives), but you cannot verify that.
The new battery could be at fault, or eliciting a pre-existing system fault that the old battery did not.
So, at this juncture …
Ordering a replacement breaker is sound.
Busting out the clamp meter is sound.
Removing the breaker is unsound.
If you’re getting impatient for the new part to arrive, a 40A fuse from a car shop would tide you over.
You asked what’s a recommended replacement for the 40A breaker. Sounds like you’ve already ordered one, but for the power levels you’re proposing, 40A sounds fine. Or 30 or 60 or 80. As long as it’s higher than your average current draw, and assuming it’s not getting cooked by butting up against a hot controller, it’ll be fine.
I repeat, in this application the role of the breaker is not to protect wiring, as with houses, it’s to protect electronics.
People overload house circuits by plugging too much stuff in. This does not apply to electric vehicles. You size the wire according to your needs. If it’s undersized for the current that your controller draws, the only valid solutions are either reducing the current or beefing up the wiring.
eee291
100 kW
Anyone mentioned precharge resistors and inrush current yet?
High current controllers have more capacitors than your typical Amazon controller.
When flipping the breaker to "on" it's basically a "short" for a short time.
Some batteries have a larger internal resistance than others (depends on chemistry and construction)
I've had varying results with just flipping it, sometimes it goes well, other times even the BMS trips because of the huge inrush current.
You can connect a resistor to both sides of the breaker and interrupt it with a switch, press it for a few seconds and then flip the breaker.
High current controllers have more capacitors than your typical Amazon controller.
When flipping the breaker to "on" it's basically a "short" for a short time.
Some batteries have a larger internal resistance than others (depends on chemistry and construction)
I've had varying results with just flipping it, sometimes it goes well, other times even the BMS trips because of the huge inrush current.
You can connect a resistor to both sides of the breaker and interrupt it with a switch, press it for a few seconds and then flip the breaker.
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Did you measure current draw with your clamp ammeter? That data point is needed to determine MCB size. I asked if you had dual batteries which need a dual MCB. Switching between batteries probably caused your MCB to fail due to the big spark when contact is made. I think that's what happened with mine.
Your lithium battery is capable of supplying way, way more Amps than a LA one. Something is drawing more than your fuse can handle.
In order to solve your problem you need to know what is happening. I suggest buying a wattmeter. https://www.amazon.com/Precision-Co...8-4-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1
In order to solve your problem you need to know what is happening. I suggest buying a wattmeter. https://www.amazon.com/Precision-Co...8-4-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&th=1
Or the fuse is playing up. Either way, yes, ought to be measured. But if a replacement resolves the issue, I’d say move on and forget about it.
JackofHearts
1 mW
I heard a pop when I flip on the breaker for both batteries. I've seen many DIY solar guys on Youtube using a big resistor to precharge the capicitors in the inverter before connecting a battery to the inverter.
I was asking questions here, because I'm not familiar with the controllers on ebikes and scooters. When I flip the breaker on, I hear a pop, but the controller is still working.... I agree with you, it is good practice to use a resistor to avoid the pops. I also agree that the internal resistance is different and I suspect that's why the MCB is tripping. The scooter powers up no matter the battery I'm using, it is just that when using the lithium battery I have to be super careful turning the throttle so the breaker won't trip.
JackofHearts
1 mW
Thanks for the link - if it comes to getting one, I will.
"Your lithium battery is capable of supplying way, way more Amps" - I agree, but was the controller designed for a LA battery only? The reason I ask is, if the controller is a 20AMP controller, it should only draw what's it is capable of no matter the battery, right?
The lithium batteries I'm using are really good, they can deliver 60AMP continuous for 1 hour per specs (LG Chem battery). Again, if the controller is 20AMP rated, it should only draw 20AMPs is what I've always thought.
Here are the specs: (I have 17 of these in series, my goal was to increase travel distance, I have Daly bluetooth BMS attached)
Type : HR37145100300
Material system :Multivariate composite lithium (remark-Multivariate composite cathode material)
Nominal Capacity :60Ah
Minimum Capacity :60Ah
Nominal Voltage :3.7V (Mean Operation Voltage)
Delivery voltage :3.50~3.60V (Within 10 days from Factory)
Charge Voltage :4.20V±0.03V (By standard charge method)
Standard charging method:1.0C constant current,4.20V constant voltage charge to 4.20V,continue charging till current deadline to ≤0.05C (25±3℃)
Standard discharging method : 1.0C constant current discharge to 2.75V,
Cell Internal Impedance :≤1.0mΩ (Internal resistance measured at AC 1KHZ after 50% charge )
Weight :0.88±0.02Kg
CC Charge :CC charge 1.0C/60A、cutoff voltage 4.20V,Capacity>60Ah 1.0C
High-Rate Discharge: DC discharge 3.0C/180A、cutoff voltage 3.0V,Capacity>60Ah
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JackofHearts
1 mW
I have measured. I can see it bounce to 30AMPs. I haven't caught an eye on it above 30 because the breaker flips and the clamp meter goes to zero real quick (I'm trying to drive and look at the clamp meter too so easy to miss what the highest number is).
JackofHearts
1 mW
I ordered a 50AMP breaker that's capable of 100v - I will start low and go high - only 7 dollars a breaker.
Car shop fuse - Those would be for 12v - not sure they'll work with 72v?
7 dollars sounds good to me. So does 50A. Plenty of headroom. Do you know the breaking curve/type for it?
Tiny linear glass fuses mightn’t be as voltage agnostic, I don’t know, but blade fuses won’t sustain an arc with any voltage I’ve tested up to 84V. The “v” shape between posts probably helps. I use the larger “maxi” versions, which might also make a difference.
Tiny linear glass fuses mightn’t be as voltage agnostic, I don’t know, but blade fuses won’t sustain an arc with any voltage I’ve tested up to 84V. The “v” shape between posts probably helps. I use the larger “maxi” versions, which might also make a difference.
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