welding wire for an invertor
 

welding wire for an invertor

Started by christopher, April 04, 2010, 01:31:16 PM

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christopher

is it ok to use #4 welding wire for an 800-1000 watt invertor? the battery will be 8' away
grainger has it for $40.00 for 25'
thanks
chris
mci5c

bevans6

I would personally use it, I've been using it to wire my race cars for many years, so I will be interested to see what the experts say.

Brian
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

Lin

Here is a chart that should help.  In short, if the inverter is 12vdc and its surge capacity is no more than 1000, #4 seems to be okay.  If the surge is between 1100 and 1500, you will need #2 wire.  Size according to the highest possible output.  What size fuse does the manufacturer recommend?  This is not an expert opinion. 

http://www.solar-electric.com/solar_inverters/inverters_for_solar_electric.htm
You don't have to believe everything you think.

christopher

good question,
what size fuse should i use?
the tv is 700 watts and the dvd player is 140 watts.
do i even nedd a fuse as is there not one built into the invertor?
Thanks
Chris
mci5c

Stormcloud

Its a real good idea to fuse the 12 volt circuit side of your inverter. It will protect the battery and YOU if you happen to be in the vicinity.

A blown fuse is an inconvenience; a blown battery can be deadly.

JMHO

Mark
Mark Morgan  
1972 MCI-7 'Papabus'
8v71N MT654 Automatic
Brandon, Manitoba, Canada in summer
somewhere near Yuma, Arizona in winter(but not 2020)

Sean

Quote from: christopher on April 04, 2010, 01:31:16 PM
is it ok to use #4 welding wire for an 800-1000 watt invertor? the battery will be 8' away

Not really.

1,000 watts is 83.3 amps at 12 volts, and #4 is just under that capacity at most rating temperatures.  A bigger issue, though, is that an 8' cable run of #4 carrying that amount of current will have a voltage drop of 3.1%, considered unacceptable by most standards.

Use a minimum of #2 for this capacity.

Quote from: christopher on April 04, 2010, 03:08:42 PM
what size fuse should i use?
the tv is 700 watts and the dvd player is 140 watts.
do i even nedd a fuse as is there not one built into the invertor?

Yes, you need a fuse.  A fuse (if any) built into the inverter is to protect only the inverter.  You need a fuse at the battery end of the cable to protect everything else -- a wrench or screwdriver being used to tighten the lugs on the inverter could easily weld itself to the bus if inadvertently touched to ground with these size cables, in an impressive shower of sparks.

If your TV really draws 700 watts and the DVD really draws 140 watts, then a 1,000-watt inverter is the minimum size you can get away with, and for that you will need a minimum 80-amp fuse (which will carry 960 watts at the nominal 12 volts, but over 1,000 watts at the actual operating voltages).

At this amperage, I favor ANL fuses, which are widely available.  ANL fuses and holders are widely used by the eardrum-shattering audio crowd, and thus found cheaply on eBay and other similar venues.  Easy to install and easy to change.

-Sean
http://OurOdyssey.BlogSpot.com
Full-timing in a 1985 Neoplan Spaceliner since 2004.
Our blog: http://OurOdyssey.BlogSpot.com

bevans6

My real curiosity was about the welding wire - is the thin stranded welding wire OK to use, or is a thicker stranded and stiffer wire better?

Brian
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

gumpy

Quote from: bevans6 on April 05, 2010, 04:02:16 AM
My real curiosity was about the welding wire - is the thin stranded welding wire OK to use, or is a thicker stranded and stiffer wire better?

Brian

I used 4/0 welding cable on my 4000 watt Trace. No problems with it.

Follow Sean's advice on size and fuse.

craig
Craig Shepard
Located in Minnesquito

http://bus.gumpydog.com - "Some Assembly Required"