The Samlex 600 watts pure sine inverter has an internal GFCI, the Samlex 300 watts doesn't, should I be concerned about electrical shock if I don't have the unit grounded? Which portable GFCI unit would you recommend?
Without a GFI or grounding and or metal cased strobes, yes you should be concerned about shock. You can get several plug-in style GFI cords or receptacles from Lowes or Home Depot starting around $15. And you can buy a 350 watt Samlex (by Cotek) inverter with a GFI receptacle. More expensive but a good inverter with a 700 watt surge rating..
I just got the inverter and holy crap it's bigger than I expected. There goes the tackle box idea. I'm just waiting on the battery and charger now.
By the way, Gregg, would you recommend me get the external fuse? If so, where can I get that same fuse holder and 125A. I went to AutoZone and the most they had were puny ones and 30A fuse. They also didn't have anything bigger than a #8.
And thanks for this DIY idea. It really inspired me to finally make one of my own. After seeing all the others here, other forums and YouTube, I didn't really like the inverters I saw for the price they were selling for. This one on the other hand makes the most sense for my two 500 BXRi and priced decently. I also have a Vagabond II so I can split up the two lights.
There is some debate about that Sean. Why don't you call Samlex in Canada and tell them you have a technical question and what you are building. They are very nice people there. If you do need a fuse and in-line fuse holder I got a great deal. Very good service I got mine here http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150266692952&ssPageName=ADME:LU:US:1123
A breaker that big would be pretty expensive. The advantage however, is that you could just reset it if you needed too. I chose 125 as that was what I read for the type of setup and it came free with the fuse holder I bought. I am going to call Samlex Monday and check my setup with them and I'll report back.
Please check the manual, it's available from the Samlex site, everyone who plans to build one should read the whole manual anyway, a lot of useful information. A quick calculation: 12V*xA=600W/0.85, 0.85->85% efficiency, so xA=706W/12V=58.83A, I think the inverter has 2*40A fuse inside.
With an extra external fuse, it serves two purposes-avoid battery shorts and allow user to reset the system easily without replacing the fuses in the inverter. Therefore, the external fuse/breaker should have a lower rating than the ones in the inverter, say 5A or 10A lower, so the external breaker would trip in case of an over-current. High current surge may blow fast acting fuses easily, and breakers would be slower (higher tolerance to short term current surge) so it should work better in this system.
400d wrote:
With an extra external fuse, it serves two purposes-avoid battery shorts and allow user to reset the system easily without replacing the fuses in the inverter. Therefore, the external fuse/breaker should have a lower rating than the ones in the inverter, say 5A or 10A lower, so the external breaker would trip in case of an over-current.High current surge may blow fast acting fuses easily, and breakers would be slower (higher tolerance to short term current surge) so it should work better in this system.
I'm a little confused. Is it better to have high amperage for an external fuse or lower?
BTW, what's your knowledge level when it comes to electronics? I barely know anything about this stuff, which is why I'm asking. I didn't put an external fuse on mine.
I was suggesting the external fuse/breaker should have a lower current rating-the external fuse is meaningless if the internal is blown first, right?
I am a beginner to electronics, what I have said is like common sense. You don't necessarily have to add an external fuse, it's not likely some odd metal object will tumble inside your system's case and short the battery. So it's there for convenience, if there's over-current draw, you just reset/replace the external breaker/fuse.
I believe the fuse the OP had, was between the inverter / battery.
So even if theres an overdraw, the inverter's fuse would go first.
I don't know much about electronics, but would the inverter's fuses protect the inverter and the stuff plugged in, if the battery has a problem? I was thinking the inverter would only protect itself, and the battery, if theres a problem with something plugged in, not necessarily the other way around.
400d wrote:
I was suggesting the external fuse/breaker should have a lower current rating-the external fuse is meaningless if the internal is blown first, right?
I am a beginner to electronics, what I have said is like common sense. You don't necessarily have to add an external fuse, it's not likely some odd metal object will tumble inside your system's case and short the battery. So it's there for convenience, if there's over-current draw, you just reset/replace the external breaker/fuse.
Ahhh. Makes sense. But is that external fuse only for the protection of the battery? When you say something will short the battery, you mean (hypothetically) that if a monkey wrench, for example, happens to land right on the + and - terminals, it would pop the fuse?
Csae wrote:
I believe the fuse the OP had, was between the inverter / battery.
So even if theres an overdraw, the inverter's fuse would go first.
I don't know much about electronics, but would the inverter's fuses protect the inverter and the stuff plugged in, if the battery has a problem? I was thinking the inverter would only protect itself, and the battery, if theres a problem with something plugged in, not necessarily the other way around.
Here's the idea:
Case 1) Both internal fuse (80A) and external fuse (75A), current draw > 75A, external fuse blew, internal fuse did not blow. Replace external fuse.
Case 2) Both internal fuse (80A) and external fuse (80A), current draw > 80A, either of the fuse will blow, depending on which one has a faster reaction time.
The external fuse should be as close to the battery terminals as possible, since a short could occur "before" the external fuse. Battery terminals should also have proper insulation.
400d wrote:
Case 1) Both internal fuse (80A) and external fuse (75A), current draw > 75A, external fuse blew, internal fuse did not blow. Replace external fuse.
Case 2) Both internal fuse (80A) and external fuse (80A), current draw > 80A, either of the fuse will blow, depending on which one has a faster reaction time.
The external fuse should be as close to the battery terminals as possible, since a short could occur "before" the external fuse. Battery terminals should also have proper insulation.
Ah, i get it.
Even if the fuse is behind the inverter, if its slightly lower then the inverter, that fuse will blow, Before the inverter's fuse and thus saving you the time needing to switch the inverter's fuses.
That being said, was the "breaker" i linked, a breaker? or just a part of a breaker? What exactly was i looking at ?
I reckon a simple small breaker would still be better then a fuse.
The main question I have now is, which inline fuse holder can I get that holds ~75A but at the same time can hold a #4 wire? I've gone to AutoZone and looked online and can't find one. Does one even exist? Most of them hold #8.
Even if the fuse is behind the inverter, if its slightly lower then the inverter, that fuse will blow, Before the inverter's fuse and thus saving you the time needing to switch the inverter's fuses.
Again, it depends on current rating and response time.
That being said, was the "breaker" i linked, a breaker? or just a part of a breaker? What exactly was i looking at ?
I reckon a simple small breaker would still be better then a fuse.
A breaker is just like a normally closed switch, which becomes open when there's over-current. Those you find are complete breakers, no extra parts are required. Breaker is a very simple device, two poles, connect one to the positive terminal and connect another to the positive terminal of the inverter.
50a, auto-reset. I can imagine that being pretty useful in needing to open the case up, but i guess there is some sort of downsides ?
I have never used an auto-reset breaker, I think it returns to normally closed state after the short/power source is removed. If that's the case, it will work just fine. Not sure if the 50A breaker will trip during full power flash recycle though.
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