Does anyone know how to calculate the size inverter that can be installed in a 2006 F250 PSD with dual batteries and alternators.

I would like to install a 1000 watt inverter, but I do not want to overload the system. The inverter will almost always be used while the engine is operating.

Thanks

 

That 1000w inverter will draw about 100 amps from your electrical system. Rule of thumb is to divide the load in watts by 10 to figure the inverter draw.
At 100 amps, assuming you have a large say 130 A alternator, you could draw the full 1000 watts for some time. However, the engine must be running, and you won't see the full 130 A output from the alternator at idle. What the alternator isn't supplying the battery is, so it will eventually run down. Now, most good inverters have a low voltage cutoff, so you won't kill the battery.

Next point is even if you have a 1000 watt inverter, will you be using the full capacity? For how long at a time? Running it with a 100 watt load for example won't take but about 10-15 amps depending on inverter efficiency. You can sustain that load for some time with the engine off, and indefinitly with the engine running. Of course now you have to worry about engine overheating if stationary. And this all assumes correct size wiring, proper installation, etc.

 

What size inverter to handle portable tv, dvd, fridge, grill, etc?

 

Thank you for the reply.

I do not expect to use anywhere near the max output. Typically, the inverter will be used for a laptop (100 watts) and possilby charging my dog's electric collar if I forget to charge it before I go bird hunting. Things like that.

With the dual alternator option, do you think it would have enough output to keep everything going?

Thanks

 

Alchymist is pretty close on the numbers.

You'll want to configure SEIC and activate it should you be running heavy loads.

My humble opinion, as someone who has a 200A master power bus in his 2005 F350? 1KW is too much to try to run on an inverter. I'm running a 600-watt Samlex pure-sine inverter (actually very clean sine-wave for only $220 distributor cost) and will be carrying a Honda EU2000i 2KW generator (small, quiet, lots of runtime for little gas) to power heavy loads.

If you're not planning on running near 1KW, why put yourself through the trouble of running the gigantic cable to it (figure 4ga. at a minimum... I'd strongly advise something a bit larger... I'm running 1/0ga) and dealing with such a heavy load? Not to mention big inverters get rather spendy.

If you really want sexy, check out the Auragen and Blackbird generator systems... PTO or belt-driven, 5-10KW output. Very, very cool (spendy too).

Customz, you can do what you need with an inverter... the inverter on a 5-10KW Honda generator!

 

Thanks tvsjr,

I have a Honda EU2000i for heavy loads.

I will go with the 600 watt Samlex as you suggested, it was my second choice. I tend to go overboard with these things sometimes!

Thanks all for your input.

 

Plan on running 4ga. to the battery to power it... good ground to the frame. Fuse at the battery and at the input to the inverter.

Make sure you get the pure-sine Samlex rather than the standard model... for the price, the pure-sine has lots of advantages.

SEIC still wouldn't be a bad idea if you pull the inverter to the limit for long durations (>15min.?)

And the EU2000i is bad-***

 

Plan on running 4ga. to the battery to power it

4ga is not needed way overkill for this.

 

I wouldn't say that 4 ga is way overkill for supporting 100 amps - actually I think a 1000 W inverter will pull something closer to 75 amps when the truck is running, but the 100 amp figure was given earlier so I'll continue to use that.

There are a number of web sites that you can go to find tables for the ampacity that a given gauge of wire will support. Just google "wire gauge ampacity" and you'll find a lot links with to that info.

It's always better to go with wire that's larger than you'll need than too small.

And don't forget to include a fuse at the battery!

 

We have a little Trip-Lite 350W inverter that plugs into the cig lighter. Runs our laptop, charges game boys, etc. Has two 110 plugs and the battery saver alarm. It was pretty inexpensive and I didnt' need to hardwire anything. Just a thought.

Mike

 

Mike do the wires get hot with runnig all of those?

 

Jeebus, here we go again. Let's not trust the guy who installs equipment in public safety vehicles to know what he's talking about.

4ga. is rated for 100 amps at 19.5 feet for a 10-degree C rise in insulation temperature (actually, this is the standard spec which Whelen, Fed Sig, and others use). Many of the "ampacity" charts given values for wire running in more friendly environments, allowing a 20-deg. Celsius rise in insulation temp. If the wire runs under the hood of a PSD, it's *HOT* to start with. 20 deg. C can turn into a fire. If you read an "ampacity" spec and it doesn't account for wire gauge, wire length, temperature rise, and bundling conditions (free air, in a bundle, etc.) then it's an incomplete chart.

The Samlex PST-60S-12A 600-watt pure-sine inverter is rated for 600 watts continuous *but* 1KW surge with an efficiency of 85%. 1000 / .85 / 13.5 = 87.15amps at surge, 600 / .85 / 13.5 = 52.29amps at 100% continuous load. Note I'm assuming 13.5VDC here... that means the truck's running and most likely idled up. Let's run the numbers again assuming the truck is off at 11.8VDC. 1000 / .85 / 11.8 = 99.7amps at surge, 600 / .85 / 11.8 = 59.82 amps at 100% continuous load.

For a 1KW inverter, the Samlex PSE-12100A 1KW inverter is specced at 85% efficiency as well, with a 2KW surge rating. 1000 / .85 / 11.8 = 99.7amps... 2000 / .85 / 11.8 = 199.4amps.

Remember, boys and girls... the "ampacity" of wire obeys Ohm's law... the amount of voltage drop (and thus generated heat) is independent of the input voltage... that's why electric companies run extremely high voltages for power transmission, then step it down to 110/220/440/480 near the customer drop.

4ga. is decidedly not overkill for this purpose. It does give the installation a bit of headroom... you'll discover very quickly that with many things (not just wire), if you don't push them to 100%, instead leave a 10-20% safety margin, you end up with far less problems. Besides, 100% would be 6ga. wire... not enough difference in price nor installation difficulty to jack with.

Mike - be careful how much you load that plug-in inverter and for how long. I've seen lighter plugs replaced in TV news units because they were running a 250-watt inverter to power an Anton Bauer battery charger, and they ran it for so long that the plug got hot and melted.

 

OK, here is what I did.

Installed a 750 watt inverter against the firewall behind the brake pedal; unless you really look for it, it is a hidden installation. I put it there because there was room and it would dramatically reduce the length of wire necessary to reach the battery.

I don't really need all of that wattage, but I would rather have a unit running at 50% than 100%, so I fused it with a 60 amp fuse.

I wired this to upfitter switch 2 (35 amp) via a 70 amp relay switch. The installation was done with #6 wire which is only about four feet at its longest length. I grounded the unit to the frame, also with #6 wire. Each connection was crimped and sealed with heat shrink and the wire was encased in plastic harness material similar to the stock wiring harness.

Tomorrow I will run some wire under the carpet and install a flush mount female AC plug in the front and back of the center console, completing the installation.

Please feel free to comment or offer any constructive criticism on my installation.

Thanks

 

'05 F250 CC SB, PSD with dual alts. I run a 2500 watt inverter mounted to the side of the bed at the rear of the truck. 3/0 copper battery cable to the unit with a 300 amp. circut breaker within a foot of the battery. For anything but the lightest of load I invoke SEIC (battery charge circut) wired through upfitter #4.

No apparent cable heating issues, voltage drop minimal. 12.5+/- at inverter when running at 1200 rpm. I can power up a 12" miter saw with no problem. The use is infrequent such as several cuts in a row. No constant use - house wiring or generator otherwise.

Smitty

 

That sounds like a hot setup...

What types of limitations do the cigarette lighter powered ones have?