Should I worry about Brand Names with Circuit Breakers?

softdown

I don't understand how DC or AC or voltage (12 or 24 or 48 or 110/120) would determine the correct fuse/circuit breaker. Point one in the right direction perhaps? Sure.  It would seem that too much current would blow/trip the fuse/circuit breaker regardless of other factors.

How does a simple fuse/circuit breaker know what is passing through it?

BB.

Fuses and Breakers (standard ones) open when they have too much current flowing through them. There is no effect of operating voltage to trip.

However, two issues of voltage. One is simply the insulation breakdown voltage (too high, and the voltage will arc from the terminals or through the plastic case. The other is the higher the voltage, the greater gap the arc will jump. More or less, voltage below 12 volts will not sustain an arc (why 12 volt systems are pretty safe and easy to find switches/etc. for).

At higher voltages, the arc "sustains" better. And DC arcs tend to sustains easier than an AC arc. Here is an example... 220 VAC vs 220 VDC:

https://www.youtube.com/watch?v=Zez2r1RPpWY

-Bill

lolcashcow

Hi guys thanks for all the replies and thank you Bill for that video.

I re-read the nissan leaf thread and the person uses:

The inverter is a Xantrex PROWatt SW True Sine Wave Inverter model SW1000.
The breaker trips at 150 amps.
The Connectors are 175 Amp Anderson SB175-02-YEL
It's run on all true copper 2 gauge wire.

Since right now there is some debate on getting either the anderson SB175 or the anderson SB 350 I could just settle for #1/0 AWG cables and use the SB175 Anderson connector. He used thinner cables but his inverter is only the SW100 version (It is essentially half as powerful as the one I am picking).

So the question is:

Should I go with the traditional set up of the Anderson SB175 connector with #1/0 AWG wires... or increase the wire size to #2/0 and grab the Anderson SB350 connector?

I'd pick up the SB175 with the bigger wire of #2/0, but it says it can only take up to #`1/0 thus I would need the  bigger connector for the bigger wire.

I personally like the idea of the #2/0 wire, but I am unsure if it would be safe to use the bigger connector SB350. I don't know how that will affect the set up? Though if I get a bigger connector I could use it later in another project that uses more power?

The max amount of power that will run through the wires would be close to 1800 watts continuous (Max inverter output) and a 3000 surge (Max inverter can handle for a few seconds). Though I will try to keep the load with he induction cooker at around 1600 watts. I am unsure if using all the power the inverter can provide would be wise. Not sure how long I will cook for. Perhaps 20 minutes? It will vary that is for sure.

BB.

A good place to start is the manual:

http://www.xantrex.com/documents/Power-Inverters/PROwatt-SW/975-0529-01-01_Rev-C(Artwork).pdf

And, some basic rule of thumbs (conservative):

• 1,800 Watts * 1/0.85 inverter eff * 1/10.5 volt batt cutoff * 1.25 NEC derating (wire+fuse) = 252 Amp rated wiring+breaker
• 1,800 Watts * 1/0.85 inverter eff * 1/10.5 volt batt cutoff = 202 Amp (no NEC derating)
  

The manual recommends 250 Amp fuse.

Next, what size wire... NEC table:
https://lugsdirect.com/WireCurrentAmpacitiesNEC-Table-301-16.htm
 4/0 AWG wire (higher temperature insulation)

And ABYC chart:
http://www.boatus.com/boattech/articles/choosing-cables-and-terminals.asp

1 AWG or 1/0 AWG would be OK.

NEC tends to be conservative, and has the cable inside conduit (poor ventilation). Open cable in an engine compartment (will you have the hood open when using to keep the wiring/inverter cool?), will not run as hot.

Most people would be hard pressed to run an AC inverter at 1,800 Watts continuous--Lots of incandencent lamps, space heaters, etc... Motors and such are usually high variable loads--And it is unlikely that you would be drawing 100% rated power for minutes/hour at a time at 10.5 volts (low battery cutoff)...

Then there is how long the wire run will be... The manual suggests 6 feet is maximum recommended. Using a voltage drop calculator with 202 amps, 6 feet and 1/0 cable, the voltage drop would be:

http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=0.3224&voltage=12&phase=dc&noofconductor=1&distance=6&distanceunit=feet&amperes=202&x=50&y=6

Voltage drop: 0.24
Voltage drop percentage: 2.00%
Voltage at the end: 11.76

If you plan on not taking the battery below 11.5 volts, and have 10.5 volt inverter shut down, and support 2x surge current, then 1/0 cable should be OK (about 1/2 volt available for fuse and connector voltage drop).

Referring to connector specifications--175 Amps is a bit below the 202 worst case current rating. And connectors can be a weak point in any system design. I do not know enough about the SB Anderson connectors (working temperature, etc.) to say that you need the next size up or not--But, again, if you are running variable loads and/or loads less than:

• 175 Amps * 10.5 volts * 0.85 inverter eff = 1,562 Watts of AC load
  

then you should be OK.

One of the problems with engineers, is we are generally tasked with "worst case" designs (highest continuous output power, lowest battery voltage, highest temperature, still be safe, etc.). It can make for some serious "over design".

I would also worry about the capability of the Nissan to supply much more than 100 Amps @ 12 volts safely/continuously (I don't remember the system rating)... That is already a lot of current/power for a 12 volt system.

-Bill

softdown

This demo is informative and interesting. Though it leaves me perplexed as to how and why Edison tried to scare the public away from Tesla's AC by electrocuting an elephant while using AC power. This demo tells me that AC is safer in critical ways. DC looks good for welding.

Thank God that Tesla's design was accepted. AC seems to be the only realistic way to power the world via a power grid. Though I am partial to Europe's usage of 177 volts instead of our bi-polar usage of 110 and 220. Pros and cons...of course.

Do we electrocute chosen prisoners with AC or DC I wonder.


BB. said:

Fuses and Breakers (standard ones) open when they have too much current flowing through them. There is no effect of operating voltage to trip.

However, two issues of voltage. One is simply the insulation breakdown voltage (too high, and the voltage will arc from the terminals or through the plastic case. The other is the higher the voltage, the greater gap the arc will jump. More or less, voltage below 12 volts will not sustain an arc (why 12 volt systems are pretty safe and easy to find switches/etc. for).

At higher voltages, the arc "sustains" better. And DC arcs tend to sustains easier than an AC arc. Here is an example... 220 VAC vs 220 VDC:



-Bill

BB.

I think discussion of pros and cons of electrocution and power sources is a bit beyond where we would go on this forum.

Otherwise, as you say, there are pros and cons to any voltage/current/frequency/AC/DC/# of Phases/etc.

Edison did experiments. Tesla did math. AC power is very math intensive and was beyond Edison's comfort zone (abilities?).

Today, there are reasons that we use DC high voltage transmission lines--And modern electronics do make things possible on a small scale that where not in the days of transformers and vacuum tubes (which where based on Edison's work and early patent--For something that Edison did not even understand the physics of at the time).

What would the ideal power system look like today with modern electronics/understanding physics--Interesting to think about--But probably of little direct use.

-Bill

Dave Angelini

Lot's of DC still in the US Navy also. I never liked the open frame CB with 1,600 amps @250Vdc. 100,000 amps interupt ratings.

They would never find you if you got in there. Not to mention all the 400 Hz. breakers with 500 VAC ratings.

Do you think they use name brands?

lolcashcow

Hi Bill!,

Thanks a lot for replying. I just noticed something. For the anderson connector I noticed that each place that sells it only offers 1 housing and 2 contacts in a kit. Do you need to buy 2 of these anderson kits? How do these plug together if they are the same type of connector?

Okay did a little search online and found this image



So they are basically turned upside down to one another then plug in? Do they stay secured this way? No need for anything else to keep them connected? So that means I need two anderson connectors?

Something else I noticed is that the SB175 the guy is using  looks pretty big in the picture for the leaf. And the SB350 is bigger!






I'm hoping the SB350 will fit? Will it be bigger than my hand?!

BB.

The standard (smaller) contacts and even the bodies are able to be on both sides of the connection (they slide over each other--think two hands sliding together palm to palm, they are not pin and sleeve connections).

The larger bodies have different options. They have different color housings that cannot inter-mate between different colors (as I understand).

-Bill

lolcashcow

BB. said:

The standard (smaller) contacts and even the bodies are able to be on both sides of the connection (they slide over each other--think two hands sliding together palm to palm, they are not pin and sleeve connections).

The larger bodies have different options. They have different color housings that cannot inter-mate between different colors (as I understand).

-Bill

I pray to god the bigger ones just slide on together to make my life easier. All of this is getting complex... quick! At least for my n00blet experience. I am a little worried now though. Did you see the picture of the SB175 on the leaf above? The SB350 is bigger, from what I saw online? I am worried the SB350 will be so huge it won't fit in now!

Maybe at this point I should also be worried about #4/0 wire size? What am I getting myself into!?

BB.

Here is an an Anderson SB350 Data Sheet:

http://www.andersonpower.com/_global-assets/downloads/pdf/ds-sb350.pdf

Here is the SB Family web page:

http://www.peigenesis.com/en/anderson-power/multipole-connectors/sb.html

-Bill

westbranch

I believe you will see the term hermaphrodite used with Anderson connectors
From Wiki
Powerpole connectors are physically and electrically hermaphroditic, thus avoiding the need to worry about which end is the plug and which the socket, or which end has the correct polarity. This is in contrast to the physically but not electrically hermaphroditic 2-wire trailer plug.

Trust me when you use them the first time .... they fit... I have used many of the smaller varieties!

zoneblue

They call it genderless. Anderson, yes, expensive but good. Theres some clones emerging, but best be careful with them.The plating is obviously key to their longevity.

softdown

These are often called forklift battery connectors. They offer different colors because many places will use several forklifts. Yellow will not match with grey etc. The largest is for 4/0 wire. The smallest would be for ~ 0/0 wire....or smaller....I would think. The wire size will dictate the proper connector.

This has all been said before of course. Why do I say it again? Most people need to hear something three times before they really learn it.

These are excellent connectors in my opinion. Big, insulated, sturdy, and hard to do it wrong. Just my type.

lolcashcow

Thank you Everyone,

So then I will need after all 2 anderson conectors. There seems to be some worry about  Anderson Conectors that are not authentic? This one is said to be authentic http://www.ebay.com/itm/Anderson-SB350-Connector-Kit-Red-4-0-Awg-6322G2-4-0-Ga-includes-Domestic-Ship-/221671744079?hash=item339caa624f What do you guys think? Also Grey Color http://www.ebay.com/itm/Anderson-SB350-Connector-Kit-Gray-4-0-Awg-6320G2-4-0-Ga-Authentic-Anderson-/370218647958?hash=item5632c04196 What color should I pick up? If that even matters?

What are you guy's thoughts of buying from ebay? Should I do it or would it not be a good decision?

I'm going to go with Bill's advice and make the whole system 'worse case scenario' proof. It will be over built but I feel it will be safer this way:

The inverter:  Xantrex prowatt sw2000 (1800W continuous 3000 Max Surge)
Copper Cables: #4/0 AWG (Cable length will be kept under 2 feet long)
http://www.amazon.com/Blue-Sea-Systems-5191-Terminal/dp/B0019ZBTV4
Blue Sea Systems 5191 Fuse Block Terminal 30-300 AMP  $17.57
http://www.amazon.com/Blue-Sea-Systems-250A-Terminal/dp/B0026KY6R0
Blue Sea Systems 250 AMP MRBF Terminal Fuse
Anderson SB350 Connector up to 450 Amps

Now I just need something that can mount on top of the battery to install these

On cable length Bill and the manual recommended under six feet. Is this over all cable length or cable  length per each connection? Ex: Battery to fuse. Fuse to Anderson Connector. Connector to inverter? I'm going to guess overall/total length?

BB.

I believe they are talking about one way cable run.

Not sure 6 feet is anything other than a magic number.

Short is better for heavy DC wiring. But it could be longer.

There can be secondary effects (inductance of the longer wiring, ringing LC signal at the switching input of the inverter, etc.). These can be addressed, if a problem. But shorter wiring will usually avoid in the first place.

-Bill

lolcashcow

BB. said:

I believe they are talking about one way cable run.

Not sure 6 feet is anything other than a magic number.

Short is better for heavy DC wiring. But it could be longer.

There can be secondary effects (inductance of the longer wiring, ringing LC signal at the switching input of the inverter, etc.). These can be addressed, if a problem. But shorter wiring will usually avoid in the first place.

-Bill

Hi Bill,

Well this is good. I will keep it as short as possible for sure. I will keep the hood open when using the inverter too so  it can get some ventilation.

What are your thoughts on buying the Anderson SB350 from Ebay? It says it is authentic. If everything in my list checks out then I should be able to place my order.

The inverter:  Xantrex prowatt sw2000 (1800W continuous 3000 Max Surge)
Copper Cables: #4/0 AWG (Cable length will be kept under 2 feet long) <-- Will get at Interstate
http://www.amazon.com/Blue-Sea-Systems-5191-Terminal/dp/B0019ZBTV4
Blue Sea Systems 5191 Fuse Block Terminal 30-300 AMP  $17.57
http://www.amazon.com/Blue-Sea-Systems-250A-Terminal/dp/B0026KY6R0
Blue Sea Systems 250 AMP MRBF Terminal Fuse
Anderson SB350 Connector up to 450 Amps   <--- Ebay okay?

Any suggestions on what to use as a mount on top of the battery?

BB.

I don't buy from ebay, but others do and generally have no problems. Your choice there.

-Bill

lolcashcow

Thanks Bil :0

Any suggestions on what to mount on top of the battery for the Fuse and Anderson Connector?

Raj174

Here is a video I found on the DC to DC converter on the Leaf. From what I can tell, 900 watts is the about the max power you could constantly pull out of the system without damaging the converter.
https://www.youtube.com/watch?v=BMhcHkOg-Mk

lolcashcow

http://insideevs.com/nissan-leaf-dcdc-converter-decoded-video/

“I was able to get the 2011-2012 Nissan Leaf DC/DC converter running on the test bench. This unit takes the 280-400VDC HV battery pack input and converts it to 13-15VDC for the 12V AUX battery charging. It is very stable at 74 Amps 13.6V output. Easily adjustable voltage output with a simple 10V PWM signal running at about 9 HZ on pin 1 and pin 3 goes to +12V to enable.

Please use at your own risk! 360VDC HV battery is very dangerous and can be lethal if handled improperly.”

Is that 900 watts? I don't know how to do the electrical math

BB.

74 amps * 13.6 volts = 1,006 Watts (DC Power)
1,006 Watts DC * 0.85 AC inverter eff = 855 Watts of 120 VAC 60 Hz power
If you where conservative (regarding the DC to DC converter in the car), you would use:

• 74 amps * 1.25 NEC derating = 93 Amp minimum rated fuse/breaker/wiring/connectors

Probably would not suggest more than 100 Amp fusing/wiring and not much more than 800 Watts or so of continuous AC power (unless you plan on deeply cycling the 12 volt battery too at the same time--Not recommended, those automotive type lead acid batteries do not, generally, like to be deeply cycled.

And 1,800 Watt AC inverter is just really too large (unless you want a lot of surge current support).

-Bill

Raj174

about, 900 watts/12 volts=75 amps. I see why Odessy9 used a 1000 watt inverter in his setup. A 1000 watt (12v x 83.3 amps) inverter really can't draw enough power to damage the converter. That will still boil water on an induction cooktop pretty quickly. 
Since this setup is application specific, you could use #4 AWG cable, an 80 amp breaker or fuse and the appropriate anderson connectors. Then when you set it up and use it, set the cooktop to 50% or 900 watts power.
If you set power higher, the breaker will trip just short of 1000 watts. 

softdown

Two feet of 4/0 copper cable would be hard to work with unless it is fine strand welding cable. For a very short distance such as this, I think you would be fine with significantly smaller cable than 4/0.

The best bargains and the worst scams can be found on ebay. I use it a lot for various reasons. Also check Amazon and our host.

westbranch

Re Anderson connectors, this guy has been around a fair time and appears to have a good feed back rate..

http://www.ebay.ca/itm/SB175A-HSG-SPG-BLUE-ANDERSON-POWER-QTY-1-/262279281054?ssPageName=ADME:B:SS:CA:3160

lolcashcow

I find it confusing since in the leaf forum someone said:

[quote="RePo"]Back to the original topic, I finally took a picture of my "Leaf to Home"- 1500 watt power inverter permanently installed inside the car.
6 ga wire feed directly from the 12v battery.  When left in "ready to drive", the built in inverter can supply up to 135 amps to the 12v system, which is more than the draw from this 120v inverter under full load.[/quote]


and also Brock:

[quote="BrockWI"]I finally got to try this out last night.  I have a Xantrex Prowatt SW2000.  I have the inverter connected with 24" #2 welding cable and big beefy jumper cable clips.  I turned the leaf on in park, with the parking break on then connected the positive to the positive on the battery, then connected the negative to the body of the top part of the motor.  I turned on the inverter to find it sitting at a nice, 13.2v.  I connected up a 1650w electric heater starting first on low at 600w, the voltage dropped a bit to 13.0v and I let it sit for a few minutes checking the connection to make sure nothing got warm.  Then I turned it up to 1650w, to my surprise the voltage still only dipped to 12.8v and some of that is likely due to the #2 wire and clips.  Again I ran it for about 5 minutes and nothing got warm.

So I think this a great back up to my backup.  We have 18kw of flooded lead acid batteries (8 L-16's) with a xantrex 6048 that produces 6000w at 240vac powering most of the load in the home (not electric dryer or evse or geothermal).  Typically I charge the batteries via 3kw of solar and the inverter has a sell mode that supports any down stream loads with excess power.  I can also charge the batteries via a Honda 2000i and a 120vac to 48 charger, an iota DLS-54-13 and had been using an idling car as backup with the smaller inverter but now I have another "silent" power source.[/quote]

Then there was a little bit of a debate between Brock and the Original poster killawatt:

[quote="BrockWI"]I am running the sw 2000 and did load it all the way up with a heater and other restive loads.  The small battery in the leaf will help out with surge, but I wouldn't recommend loading it more than 1500w continuous, just to be safe.[/quote]

[quote="KillaWhat"][quote="LeftieBiker"]I'd definitely go with a much larger accessory battery. Maybe a "marine" hybrid starting/storage battery...[/quote]

This is not the route to take.
The "size" of the Accessory 12 volt battery will not help your cause.
Perhaps initially (like the first 2 minutes), then the DC to DC converter will see the load, and begin trying to make up for the loss (charge).

The bottom line is you can only sustain the load the the DC to DC converter can supply.

But now you have introduced a battery with more capacity and consequently requires more power to charge when it gets low, so your requirements are now more variable, and possibly much higher than you intended.

The 1000 Watt continuous pure sine wave is the way to go.
It has something up it's sleeve in a short highload condition, and if you go bigger, your run time drops so much as to be useless.[/quote]

And some good advice I can follow at this point that also agrees with what you guy's are saying:

[quote="brettcgb"]
I wouldn't go much above half the converters capacity - the car itself needs power to run. I don't know what the converter can sustain indefinitely, but 1000W should be possible for the short term (30 minutes).[/quote]

So I will just keep loads to 1000W max to no more than 30minutes? I already received the bigger inverter and I can't take it back unless I incur shipping and return fee losses. I don't think its a loss because I do plan on getting some deep cycle batteries eventually and solar panels. This will likely take me 3-5 years so if the unit can hold until then it would be nice.

My plan has always been to get 2k watts in solar panels at some point with a battery storage system now the thing will bbe hoping the inverter will last for that long.

For the cabling, fuse, and connector I'd still like to go with the bigger set up, but I am unsure if that will be wise at this point. I find it all confusing as I believe I read other sources that quoted the dc to dc converter power to 1.5k watts.

lolcashcow

Well I was looking around in the leaf forum for some info on the 12v system on the nissan leaf and stumbled on a post by Phil Sadow (an electrical engineer in Berkeley) talking about the DC to DC converter. He is the guy that aded a  propane-powered gas-turbine range extender to his nissan leaf http://www.greencarreports.com/news/1070677_2012-nissan-leaf-gets-unofficial-jet-powered-range-extender-quick-charger Anyway he mentions that the DC to DC converter can suply up to about 1.7kw, so it might be that 900 watts is not all the dc to dc converter can supply. I added his quote below:


"The Leaf's DC-DC converter can supply up to about 1.7kW or 135a. This unit takes ~400v power from the traction battery and makes approximately 13 volts. (varies according to charge requirements of the 12v aux battery) It should be able to power up to 1.5kW of external load with no problems, provided most of the accessories are left off.

One interesting thing is, unlike the 12v system on a ICE car, there is almost no voltage sag. The DC-DC converter is a high-frequency switch mode converter, so it can respond very fast to high current surges, whereas a normal ICE car alternator cannot, and it's also RPM dependant for maximum output.

WARNING: NEVER connect anything directly to the negative post of the Leaf's 12v aux battery! This is a current sensor and doing so will disrupt the charging system! (Connect all accessories to the body ground, or, if high-current, the black wire screwed to the top of the DC-DC JB. (Behind the inverter)

Note: I have not tested it at full load for an extended period of time, so there may be some thermal limiting that could cause output to drop after long runs of high-current use.

Here's my test:


-Phil"


So if this is true we should still be on business for the worst case scenario set up?

The inverter:  Xantrex prowatt sw2000 (1800W continuous 3000 Max Surge)
Copper Cables: #4/0 AWG (Cable length will be kept under 2 feet long)
http://www.amazon.com/Blue-Sea-Systems-5191-Terminal/dp/B0019ZBTV4
Blue Sea Systems 5191 Fuse Block Terminal 30-300 AMP  $17.57
http://www.amazon.com/Blue-Sea-Systems-250A-Terminal/dp/B0026KY6R0
Blue Sea Systems 250 AMP MRBF Terminal Fuse
Anderson SB350 Connector up to 450 Amps

Brock

Very interesting stuff in that youtube video.  I can't say for sure, but I have a 2013 Leaf and I know I ran 1650 watts for just over 5 minutes and the voltage never dropped so at that point the DC-DC converter was keeping up.  Having watched that video now I would not recommend doing what I did.  Maybe it is similar to an alternator where it's rated for 80 amps but if you run it at 80 amps for 2 hours it will burn out, sort of like peak vs continuous loading.

Or maybe on the 2013 version has a different DC-DC converter?  The 11-12's are definitely laid out quite differently, the 11-12's have the charger in the back and the 13's and newer they are in the inverter stack up front.

I can say I ran my setup pulling 750w AC to feed the iota DLS-54-13 for about two hours no problem.

Hope this helps.

lolcashcow

This is going to be tough. The induction cook top has different power levels but 1 and 2 are only 200w and 500w respectively. However these cycle on and off to try and hold a proper temp. This will be less than optimal However, levels 3 and 4 are supposed to be 800W and 1000W, but draw actually 1000W and 1100W respectively. This is from the comments on the cook top they checked it with a killawatt unit. I would need at least 1000 watts probably for 30 minutes. I would prefer at least 1200w to be able to cover lv 4 power setting to be  honest....

westbranch

BILL, this thread is sticking at the pic a few posts up, did it yesterday and again today...?? thought that got fixed a few days ago