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What maximum power inverter for car?

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  What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-15 08:14 -0700
    Re: What maximum power inverter for car? "Carl Ijames" <carl.ijamesDDD@EEEverizon.net> - 2017-05-15 12:29 -0400
      Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-15 10:02 -0700
        Re: What maximum power inverter for car? Tim Wescott <seemywebsite@myfooter.really> - 2017-05-15 12:43 -0500
        Re: What maximum power inverter for car? bloggs.fredbloggs.fred@gmail.com - 2017-05-15 10:59 -0700
        Re: What maximum power inverter for car? "Carl Ijames" <carl.ijamesDDD@EEEverizon.net> - 2017-05-15 14:18 -0400
      Re: What maximum power inverter for car? oldschool@tubes.com - 2017-05-15 14:01 -0400
        Re: What maximum power inverter for car? Don Y <blockedofcourse@foo.invalid> - 2017-05-15 14:14 -0700
    Re: What maximum power inverter for car? tabbypurr@gmail.com - 2017-05-15 10:38 -0700
      Re: What maximum power inverter for car? Tim Wescott <seemywebsite@myfooter.really> - 2017-05-15 13:10 -0500
        Re: What maximum power inverter for car? tabbypurr@gmail.com - 2017-05-15 12:56 -0700
    Re: What maximum power inverter for car? Jon Elson <jmelson@wustl.edu> - 2017-05-15 13:53 -0500
      Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-15 13:00 -0700
        Re: What maximum power inverter for car? "Carl Ijames" <carl.ijamesDDD@EEEverizon.net> - 2017-05-15 17:09 -0400
        Re: What maximum power inverter for car? Don Y <blockedofcourse@foo.invalid> - 2017-05-15 14:15 -0700
          Re: What maximum power inverter for car? mike <ham789@netzero.net> - 2017-05-15 17:34 -0700
            Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-15 17:41 -0700
              Re: What maximum power inverter for car? Don Y <blockedofcourse@foo.invalid> - 2017-05-15 18:14 -0700
                Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-15 19:34 -0700
            Re: What maximum power inverter for car? Don Y <blockedofcourse@foo.invalid> - 2017-05-15 18:10 -0700
        Re: What maximum power inverter for car? Jon Elson <jmelson@wustl.edu> - 2017-05-15 16:28 -0500
        Re: What maximum power inverter for car? tabbypurr@gmail.com - 2017-05-15 15:43 -0700
          Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-15 17:44 -0700
            Re: What maximum power inverter for car? tabbypurr@gmail.com - 2017-05-15 17:59 -0700
              Re: What maximum power inverter for car? Chris Jones <lugnut808@spam.yahoo.com> - 2017-05-16 21:40 +1000
                Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-16 08:03 -0700
                  Re: What maximum power inverter for car? tabbypurr@gmail.com - 2017-05-16 09:08 -0700
                    Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-16 09:19 -0700
                      Re: What maximum power inverter for car? tabbypurr@gmail.com - 2017-05-16 09:36 -0700
                      Re: What maximum power inverter for car? Jon Elson <jmelson@wustl.edu> - 2017-05-16 13:34 -0500
                        Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-16 12:52 -0700
                          Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-16 13:27 -0700
                          Re: What maximum power inverter for car? Ralph Barone <ralph@invalid.com> - 2017-05-17 02:26 +0000
                            Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-16 21:50 -0700
                              Re: What maximum power inverter for car? "Carl Ijames" <carl.ijamesDDD@EEEverizon.net> - 2017-05-17 10:46 -0400
                                Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-17 22:31 -0700
                                  Re: What maximum power inverter for car? "Carl Ijames" <carl.ijamesDDD@EEEverizon.net> - 2017-05-18 10:26 -0400
                                    Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-18 08:23 -0700
                            Re: What maximum power inverter for car? Jon Elson <jmelson@wustl.edu> - 2017-05-17 13:59 -0500
                              Re: What maximum power inverter for car? Ralph Barone <ralph@invalid.com> - 2017-05-18 01:02 +0000
                      Re: What maximum power inverter for car? "Carl Ijames" <carl.ijamesDDD@EEEverizon.net> - 2017-05-16 15:34 -0400
                      Re: What maximum power inverter for car? mike <ham789@netzero.net> - 2017-05-16 15:48 -0700
                  Re: What maximum power inverter for car? Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-16 13:05 -0400
                    Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-16 11:12 -0700
        Re: What maximum power inverter for car? Jasen Betts <jasen@xnet.co.nz> - 2017-05-23 07:02 +0000
          Re: What maximum power inverter for car? edward.ming.lee@gmail.com - 2017-05-23 07:29 -0700
    Re: What maximum power inverter for car? Don Y <blockedofcourse@foo.invalid> - 2017-05-15 14:09 -0700
    Re: What maximum power inverter for car? Jasen Betts <jasen@xnet.co.nz> - 2017-05-23 06:43 +0000
      Re: What maximum power inverter for car? Neon John <no@never.com> - 2017-05-27 12:49 -0400

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#460353 — What maximum power inverter for car?

Looking into high power inverter to run off the car.  But for 1000W, it's likely draining 80A or 90A from the alternator.  Does that mean the battery will die even when the engine is running?

I believe most alternators are around 50A, so max power of 600W?

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#460366

wrote in message 
news:b2e24c21-5934-4111-ac97-2ef1d4df4aca@googlegroups.com...

Looking into high power inverter to run off the car.  But for 1000W, it's 
likely draining 80A or 90A from the alternator.  Does that mean the battery 
will die even when the engine is running?

I believe most alternators are around 50A, so max power of 600W?
=======================================================

Yes, the battery will still be discharging to make up whatever the 
alternator can't source, and yes, the alternator won't be happy for too many 
hours at max output.  I don't know if the low end is really down at 50 or 
60A , but many cars have alternators rated at 130A or more and I think 
80-100A is typical. What kind of car do you want to do this with?  Go to an 
auto parts website like autozone.com or rockauto.com and look up a 
replacement alternator for it, and they should list the specs.  For grins I 
chose a 2010 Toyota Camry 4 cyl completely at random and autozone says 100A. 
Make your inverter connection to the output stud on the alternator and 
you'll save the voltage drop in the wire from alternator to battery.

-- 
Regards,
Carl Ijames

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#460372

On Monday, May 15, 2017 at 9:29:54 AM UTC-7, Carl Ijames wrote:
> wrote in message 
> news:b2e24c21-5934-4111-ac97-2ef1d4df4aca@googlegroups.com...
> 
> Looking into high power inverter to run off the car.  But for 1000W, it's 
> likely draining 80A or 90A from the alternator.  Does that mean the battery 
> will die even when the engine is running?
> 
> I believe most alternators are around 50A, so max power of 600W?
> =======================================================
> 
> Yes, the battery will still be discharging to make up whatever the 
> alternator can't source, and yes, the alternator won't be happy for too many 
> hours at max output.  I don't know if the low end is really down at 50 or 
> 60A , but many cars have alternators rated at 130A or more and I think 
> 80-100A is typical. What kind of car do you want to do this with?  Go to an 
> auto parts website like autozone.com or rockauto.com and look up a 
> replacement alternator for it, and they should list the specs.  For grins I 
> chose a 2010 Toyota Camry 4 cyl completely at random and autozone says 100A. 
> Make your inverter connection to the output stud on the alternator and 
> you'll save the voltage drop in the wire from alternator to battery.

Got a Toyota Sienna.  I think it outputs 50A at idle and 120A at 5000RPM or so.  Do i need to step on the gas to get the higher RPM, even when the car is not moving?

Perhaps tieing a controller into the throttle when voltage is getting too low?

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#460382

On Mon, 15 May 2017 10:02:31 -0700, edward.ming.lee wrote:

> On Monday, May 15, 2017 at 9:29:54 AM UTC-7, Carl Ijames wrote:
>> wrote in message
>> news:b2e24c21-5934-4111-ac97-2ef1d4df4aca@googlegroups.com...
>> 
>> Looking into high power inverter to run off the car.  But for 1000W,
>> it's likely draining 80A or 90A from the alternator.  Does that mean
>> the battery will die even when the engine is running?
>> 
>> I believe most alternators are around 50A, so max power of 600W?
>> =======================================================
>> 
>> Yes, the battery will still be discharging to make up whatever the
>> alternator can't source, and yes, the alternator won't be happy for too
>> many hours at max output.  I don't know if the low end is really down
>> at 50 or 60A , but many cars have alternators rated at 130A or more and
>> I think 80-100A is typical. What kind of car do you want to do this
>> with?  Go to an auto parts website like autozone.com or rockauto.com
>> and look up a replacement alternator for it, and they should list the
>> specs.  For grins I chose a 2010 Toyota Camry 4 cyl completely at
>> random and autozone says 100A.
>> Make your inverter connection to the output stud on the alternator and
>> you'll save the voltage drop in the wire from alternator to battery.
> 
> Got a Toyota Sienna.  I think it outputs 50A at idle and 120A at 5000RPM
> or so.  Do i need to step on the gas to get the higher RPM, even when
> the car is not moving?
> 
> Perhaps tieing a controller into the throttle when voltage is getting
> too low?

You need to look up the specs for your car, so that you don't have to 
preface statements with "I think".

Having some way to make it do a high idle is probably a good idea, 
although a modern car will probably try to defeat you at every turn.  
Amateur radio operators probably know how to do this, although a lot of 
the really serious ones I've met drive SUVs, and probably know how to get 
a camping package or an aftermarket alternator that puts out more juice.

Given that the Sienna is a fairly large minivan there may possibly be a 
camper kit that you could put on it -- limber up your fingers and 
meditate to maximize your Google-Fu, and get to it.

Failing that, if you know your battery then you should know how long you 
could operate at full power before you need to go to high idle or drive 
around for a bit.

-- 

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!

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#460385

On Monday, May 15, 2017 at 1:02:35 PM UTC-4, edward....@gmail.com wrote:
> On Monday, May 15, 2017 at 9:29:54 AM UTC-7, Carl Ijames wrote:
> > wrote in message 
> > news:b2e24c21-5934-4111-ac97-2ef1d4df4aca@googlegroups.com...
> > 
> > Looking into high power inverter to run off the car.  But for 1000W, it's 
> > likely draining 80A or 90A from the alternator.  Does that mean the battery 
> > will die even when the engine is running?
> > 
> > I believe most alternators are around 50A, so max power of 600W?
> > =======================================================
> > 
> > Yes, the battery will still be discharging to make up whatever the 
> > alternator can't source, and yes, the alternator won't be happy for too many 
> > hours at max output.  I don't know if the low end is really down at 50 or 
> > 60A , but many cars have alternators rated at 130A or more and I think 
> > 80-100A is typical. What kind of car do you want to do this with?  Go to an 
> > auto parts website like autozone.com or rockauto.com and look up a 
> > replacement alternator for it, and they should list the specs.  For grins I 
> > chose a 2010 Toyota Camry 4 cyl completely at random and autozone says 100A. 
> > Make your inverter connection to the output stud on the alternator and 
> > you'll save the voltage drop in the wire from alternator to battery.
> 
> Got a Toyota Sienna.  I think it outputs 50A at idle and 120A at 5000RPM or so.  Do i need to step on the gas to get the higher RPM, even when the car is not moving?

No- the regulator will just back off the field current to keep the battery voltage at 14.4V.

> 
> Perhaps tieing a controller into the throttle when voltage is getting too low?

No.

http://alumni.media.mit.edu/~nathan/nepal/ghatta/alternator.html

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#460393

wrote in message 
news:b16b83b4-4c34-4ccb-a998-6e3e8522f694@googlegroups.com...

On Monday, May 15, 2017 at 9:29:54 AM UTC-7, Carl Ijames wrote:
> wrote in message
> news:b2e24c21-5934-4111-ac97-2ef1d4df4aca@googlegroups.com...
>
> Looking into high power inverter to run off the car.  But for 1000W, it's
> likely draining 80A or 90A from the alternator.  Does that mean the 
> battery
> will die even when the engine is running?
>
> I believe most alternators are around 50A, so max power of 600W?
> =======================================================
>
> Yes, the battery will still be discharging to make up whatever the
> alternator can't source, and yes, the alternator won't be happy for too 
> many
> hours at max output.  I don't know if the low end is really down at 50 or
> 60A , but many cars have alternators rated at 130A or more and I think
> 80-100A is typical. What kind of car do you want to do this with?  Go to 
> an
> auto parts website like autozone.com or rockauto.com and look up a
> replacement alternator for it, and they should list the specs.  For grins 
> I
> chose a 2010 Toyota Camry 4 cyl completely at random and autozone says 
> 100A.
> Make your inverter connection to the output stud on the alternator and
> you'll save the voltage drop in the wire from alternator to battery.

Got a Toyota Sienna.  I think it outputs 50A at idle and 120A at 5000RPM or 
so.  Do i need to step on the gas to get the higher RPM, even when the car 
is not moving?

Perhaps tieing a controller into the throttle when voltage is getting too 
low?
=========================================================

Rockauto and autozone both say a 2015 Sienna has a 150A alternator.  I 
haven't seen any official specs for idle output but you should get full 
output by 2000 rpm or 2500 for sure.  The voltage regulator is listed as 
"internal", but I don't know if the pcm can modulate that or not so it may 
do better at idle than 50A.   I know that on later GM's the pcm controls the 
alternator output but I'm not familiar with Toyotas.  My guess is yes, if 
you want full output to an inverter you will have to step on the gas a bit 
to get the rpms up, and shut off everything you can like headlights, drls, 
and climate control (kill both the compressor and the internal fan).  The 
engine shouldn't overheat but keep an eye on it.  Get a clamp-on dc ammeter 
good for 150-200 A, clip it on the alternator output wire, turn on all the 
loads you can (headlights on bright, foot on the brake, ac fan on max, 
seatwarmers on, anything you can plug into the cigarette lighter like a 
spotlight or air compressor) and see what the output is at idle and above. 
You say 1000W, but is that continuous or an intermittent load?  If it's 
intermittent you could probably get away with idling, and let the battery 
carry it on the peaks.

-- 
Regards,
Carl Ijames

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#460404

On Mon, 15 May 2017 12:29:08 -0400, "Carl Ijames"
<carl.ijamesDDD@EEEverizon.net> wrote:

>wrote in message 
>news:b2e24c21-5934-4111-ac97-2ef1d4df4aca@googlegroups.com...
>
>Looking into high power inverter to run off the car.  But for 1000W, it's 
>likely draining 80A or 90A from the alternator.  Does that mean the battery 
>will die even when the engine is running?
>
>I believe most alternators are around 50A, so max power of 600W?
>=======================================================
>
>Yes, the battery will still be discharging to make up whatever the 
>alternator can't source, and yes, the alternator won't be happy for too many 
>hours at max output.  I don't know if the low end is really down at 50 or 
>60A , but many cars have alternators rated at 130A or more and I think 
>80-100A is typical. What kind of car do you want to do this with?  Go to an 
>auto parts website like autozone.com or rockauto.com and look up a 
>replacement alternator for it, and they should list the specs.  For grins I 
>chose a 2010 Toyota Camry 4 cyl completely at random and autozone says 100A. 
>Make your inverter connection to the output stud on the alternator and 
>you'll save the voltage drop in the wire from alternator to battery.

I'm curious. How do you know the amperage needed to run that inverter?
(Or any inverter). For example, I have a 300W inverter that plugs into
the cig lighter in a car. I dont know how much amps it draws, but it has
to be less than 20A, because cig lighters are usually fused at 20A or
less. I use this inverter mostly for a laptop computer, so I can use the
laptop at WIFI spots from inside the car. I know the laptop dont need
the full 300W, but it still uses some power. I have run that inverter
for as much as 6 hours, without running the car engine. Only once did I
drain the battery enough that the car would not start, but that was over
6 hours use on a weak battery, and with the dome light turned on most of
the time too. (I had the battery tested after that, and it needed to be
replaced). 

I have a friend who bought an older Ford van, which came with a camper
package, including a TV, VCR, and a built in 1200W inverter. The van's
altternator was 140A. For some reason that alternator or the regulator
kept failing, and he said it cost a fortune to repair. He said he did
not need or use the inverter, so he disconnected it. He dont use a VCR,
and the analog TV is worthless without a converter box for on the air
tv. Anyhow, after spending lots of money on alternator repairs, he
changed it to a standard 60 or 65A Chevy alt with built in regulator. 
(That took a little modification of the brackets). 
He has not had any problems since. Aside from a few extra (dome) lights
in the rear, it's just a basic vehicle now, without the inverter and
tv/vcr. So he dont need all that extra amperage.

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#460433

On 5/15/2017 11:01 AM, oldschool@tubes.com wrote:
> I'm curious. How do you know the amperage needed to run that inverter?

Power = Amps * Volts

With all things consumer, there's a bit of tongue inserted in cheek.
I.e., they may assume your battery is at 14.4V instead of *9* (which
is where it will be when the engine is cranking).   And, may simply
indicate the *rating* of the components used inside -- I've got a
2200VA UPS plugged into a 15A mains circuit (clearly the branch
circuit won't be able to supply that 2200VA!)

> (Or any inverter). For example, I have a 300W inverter that plugs into
> the cig lighter in a car. I dont know how much amps it draws, but it has
> to be less than 20A, because cig lighters are usually fused at 20A or
> less. I use this inverter mostly for a laptop computer, so I can use the
> laptop at WIFI spots from inside the car. I know the laptop dont need
> the full 300W, but it still uses some power. I have run that inverter

Laptop is probably 40-60W.  I have a portable inverter for emergency use
that is wired directly to the *battery*, with its own internal fuse.

> for as much as 6 hours, without running the car engine. Only once did I
> drain the battery enough that the car would not start, but that was over
> 6 hours use on a weak battery, and with the dome light turned on most of
> the time too. (I had the battery tested after that, and it needed to be
> replaced).
>
> I have a friend who bought an older Ford van, which came with a camper
> package, including a TV, VCR, and a built in 1200W inverter. The van's
> altternator was 140A. For some reason that alternator or the regulator
> kept failing, and he said it cost a fortune to repair. He said he did
> not need or use the inverter, so he disconnected it. He dont use a VCR,
> and the analog TV is worthless without a converter box for on the air
> tv. Anyhow, after spending lots of money on alternator repairs, he
> changed it to a standard 60 or 65A Chevy alt with built in regulator.
> (That took a little modification of the brackets).

Often, all you have to do is replace the diode trio ("bridge") inside
the alternator.  Usually a handful of dollars and 10 minutes of
your time (given that you have to plan on removing and reinstalling
*an* alternator, regardless).

> He has not had any problems since. Aside from a few extra (dome) lights
> in the rear, it's just a basic vehicle now, without the inverter and
> tv/vcr. So he dont need all that extra amperage.

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#460381

On Monday, 15 May 2017 16:14:05 UTC+1, edward....@gmail.com  wrote:
> Looking into high power inverter to run off the car.  But for 1000W, it's likely draining 80A or 90A from the alternator.  Does that mean the battery will die even when the engine is running?
> 
> I believe most alternators are around 50A, so max power of 600W?

ICBW but IIRC if one messes with the voltage regulation they can deliver much more voltage at rated current, increasing output power greatly. That does mean using a separate alternator for your power abstraction - and a suitable belt.


NT

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#460387

On Mon, 15 May 2017 10:38:16 -0700, tabbypurr wrote:

> On Monday, 15 May 2017 16:14:05 UTC+1, edward....@gmail.com  wrote:
>> Looking into high power inverter to run off the car.  But for 1000W,
>> it's likely draining 80A or 90A from the alternator.  Does that mean
>> the battery will die even when the engine is running?
>> 
>> I believe most alternators are around 50A, so max power of 600W?
> 
> ICBW but IIRC if one messes with the voltage regulation they can deliver
> much more voltage at rated current, increasing output power greatly.
> That does mean using a separate alternator for your power abstraction -
> and a suitable belt.
> 
> 
> NT

Lots of work in a car with a serpentine belt, but possibly doable if 
there's room.

A herkier alternator is probably better, if you want to get into things 
that deep.

-- 

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!

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#460415

On Monday, 15 May 2017 19:11:04 UTC+1, Tim Wescott  wrote:
> On Mon, 15 May 2017 10:38:16 -0700, tabbypurr wrote:
> > On Monday, 15 May 2017 16:14:05 UTC+1, edward....@gmail.com  wrote:

> >> Looking into high power inverter to run off the car.  But for 1000W,
> >> it's likely draining 80A or 90A from the alternator.  Does that mean
> >> the battery will die even when the engine is running?
> >> 
> >> I believe most alternators are around 50A, so max power of 600W?
> > 
> > ICBW but IIRC if one messes with the voltage regulation they can deliver
> > much more voltage at rated current, increasing output power greatly.
> > That does mean using a separate alternator for your power abstraction -
> > and a suitable belt.

> Lots of work in a car with a serpentine belt, but possibly doable if 
> there's room.
> 
> A herkier alternator is probably better, if you want to get into things 
> that deep.

On an old car with lots of space, fairly easy. On a new extremely compact one with lots of things running on 1 or 2 belts, not as easy.


NT

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#460401

edward.ming.lee@gmail.com wrote:

> Looking into high power inverter to run off the car.  But for 1000W, it's
> likely draining 80A or 90A from the alternator.  Does that mean the
> battery will die even when the engine is running?
> 
> I believe most alternators are around 50A, so max power of 600W?
What the heck are you running in the car that actually NEEDS 1 KW?

Jon

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#460417

On Monday, May 15, 2017 at 11:51:07 AM UTC-7, Jon Elson wrote:
> edward.ming.lee@gmail.com wrote:
> 
> > Looking into high power inverter to run off the car.  But for 1000W, it's
> > likely draining 80A or 90A from the alternator.  Does that mean the
> > battery will die even when the engine is running?
> > 
> > I believe most alternators are around 50A, so max power of 600W?
> What the heck are you running in the car that actually NEEDS 1 KW?
> 
> Jon

Good question.  Knew someone would ask.  Running a 1200W food warmer for an hour, until i can hook it up to the engine heat/cool system.  Might not need 1000W, but at least 700W to 800W.

Might be easier just to hook up a bank of batteries.

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#460432

wrote in message 
news:4a9c7572-526a-4687-bd66-2eea9c3036dc@googlegroups.com...

On Monday, May 15, 2017 at 11:51:07 AM UTC-7, Jon Elson wrote:
> edward.ming.lee@gmail.com wrote:
>
> > Looking into high power inverter to run off the car.  But for 1000W, 
> > it's
> > likely draining 80A or 90A from the alternator.  Does that mean the
> > battery will die even when the engine is running?
> >
> > I believe most alternators are around 50A, so max power of 600W?
> What the heck are you running in the car that actually NEEDS 1 KW?
>
> Jon

Good question.  Knew someone would ask.  Running a 1200W food warmer for an 
hour, until i can hook it up to the engine heat/cool system.  Might not need 
1000W, but at least 700W to 800W.

Might be easier just to hook up a bank of batteries.
========================================================

Will you be stationary?  I guess I was assuming that before, from your 
idling questions.  If so, just get one of those $89 on sale harbor freight 
700 watt generators if that would be just enough, or the 4000 watt one for 
about $300.  If you are driving around but it is a temporary fix until you 
plumb into the heater loop for hot water, then just use the 1000W inverter 
and don't worry about idling unless you spend a lot of time doing it.  It 
may not be optimal but it will get you up and running for now.  The battery 
will go down a bit at idle but will charge back up when you start moving 
again.  Get one of those $10-15 ebay voltmeters that plug into the cigarette 
lighter if you want to keep an eye on the system voltage while the engine is 
running and the battery voltage with engine off, there's even a cute one 
with two usb ports for phone charging.

(If the inverter draws 80A and the alt can source 50A at idle that is a 
battery draw of 30A so the battery will last about three times longer idling 
than with engine off and my guess is that on just battery it could last 
40-50 minutes completely discharging the battery, so my swag is that you 
could idle for 20 minutes at a time without discharging the battery too 
deeply before you need to rev the engine back up.  Brief stops as an ice 
cream truck ok, parking for two hours as a roach coach not so much :-).)
-- 
Regards,
Carl Ijames

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#460434

On 5/15/2017 1:00 PM, edward.ming.lee@gmail.com wrote:
> Good question.  Knew someone would ask.  Running a 1200W food warmer for an
> hour, until i can hook it up to the engine heat/cool system.  Might not need
> 1000W, but at least 700W to 800W.
>
> Might be easier just to hook up a bank of batteries.

Or, a small propane powered genset.

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#460444

On 5/15/2017 2:15 PM, Don Y wrote:
> On 5/15/2017 1:00 PM, edward.ming.lee@gmail.com wrote:
>> Good question.  Knew someone would ask.  Running a 1200W food warmer
>> for an
>> hour, until i can hook it up to the engine heat/cool system.  Might
>> not need
>> 1000W, but at least 700W to 800W.
>>
>> Might be easier just to hook up a bank of batteries.
>
> Or, a small propane powered genset.

Or a propane powered heater.
Or a 12V battery powered heater.
Watts is watts.  No need to crank the volts up to run
a resistor.
Start with warm food and good insulation.

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#460447

On Monday, May 15, 2017 at 5:36:20 PM UTC-7, mike wrote:
> On 5/15/2017 2:15 PM, Don Y wrote:
> > On 5/15/2017 1:00 PM, edward.ming.lee@gmail.com wrote:
> >> Good question.  Knew someone would ask.  Running a 1200W food warmer
> >> for an
> >> hour, until i can hook it up to the engine heat/cool system.  Might
> >> not need
> >> 1000W, but at least 700W to 800W.
> >>
> >> Might be easier just to hook up a bank of batteries.
> >
> > Or, a small propane powered genset.

Tried that, but generators are noisy and hard to start.  Good generators cost as much as a used car.

> 
> Or a propane powered heater.
> Or a 12V battery powered heater.
> Watts is watts.  No need to crank the volts up to run
> a resistor.

Still need upward of 50A and difficult to run wires.  120V 5A can be much easier to wire.

> Start with warm food and good insulation.

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#460453

On 5/15/2017 5:41 PM, edward.ming.lee@gmail.com wrote:
> On Monday, May 15, 2017 at 5:36:20 PM UTC-7, mike wrote:
>> On 5/15/2017 2:15 PM, Don Y wrote:
>>> On 5/15/2017 1:00 PM, edward.ming.lee@gmail.com wrote:
>>>> Good question.  Knew someone would ask.  Running a 1200W food warmer
>>>> for an
>>>> hour, until i can hook it up to the engine heat/cool system.  Might
>>>> not need
>>>> 1000W, but at least 700W to 800W.
>>>>
>>>> Might be easier just to hook up a bank of batteries.
>>>
>>> Or, a small propane powered genset.
>
> Tried that, but generators are noisy and hard to start.  Good generators
> cost as much as a used car.

My first google hit:
<https://www.amazon.com/Sportsman-GEN4000LP-Starting-Portable-Generator/dp/B004BKI0UW>
~4KW, 10 hour run time (at 2KW), $300 (LPG tank not included)

The (big) downside to propane is the risk of explosion if not properly
maintained.

>> Or a propane powered heater.
>> Or a 12V battery powered heater.
>> Watts is watts.  No need to crank the volts up to run
>> a resistor.
>
> Still need upward of 50A and difficult to run wires.  120V 5A can be much easier to wire.
>
>> Start with warm food and good insulation.
>

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#460466

On Monday, May 15, 2017 at 6:13:56 PM UTC-7, Don Y wrote:
> On 5/15/2017 5:41 PM, edward.ming.lee@gmail.com wrote:
> > On Monday, May 15, 2017 at 5:36:20 PM UTC-7, mike wrote:
> >> On 5/15/2017 2:15 PM, Don Y wrote:
> >>> On 5/15/2017 1:00 PM, edward.ming.lee@gmail.com wrote:
> >>>> Good question.  Knew someone would ask.  Running a 1200W food warmer
> >>>> for an
> >>>> hour, until i can hook it up to the engine heat/cool system.  Might
> >>>> not need
> >>>> 1000W, but at least 700W to 800W.
> >>>>
> >>>> Might be easier just to hook up a bank of batteries.
> >>>
> >>> Or, a small propane powered genset.
> >
> > Tried that, but generators are noisy and hard to start.  Good generators
> > cost as much as a used car.
> 
> My first google hit:
> <https://www.amazon.com/Sportsman-GEN4000LP-Starting-Portable-Generator/dp/B004BKI0UW>
> ~4KW, 10 hour run time (at 2KW), $300 (LPG tank not included)

I would want auto start, if i have to use generator.  Gave up recoil start after a while.  If we have to recoil start our cars, i think lots of people would give up driving.

Don't know how noisy that one is.

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#460452

On 5/15/2017 5:34 PM, mike wrote:
> On 5/15/2017 2:15 PM, Don Y wrote:
>> On 5/15/2017 1:00 PM, edward.ming.lee@gmail.com wrote:
>>> Good question.  Knew someone would ask.  Running a 1200W food warmer
>>> for an
>>> hour, until i can hook it up to the engine heat/cool system.  Might
>>> not need
>>> 1000W, but at least 700W to 800W.
>>>
>>> Might be easier just to hook up a bank of batteries.
>>
>> Or, a small propane powered genset.
>
> Or a propane powered heater.

I suspect the "food warmer" has mechanical constraints related
to *food* warming.  :>

> Or a 12V battery powered heater.

12V into a heater just eliminates the inefficiency of the inverter.
But, you still need 80A from that battery.  (hence my suggestion to
use a *second* battery that you treat sacrificially; stealing *some*
power from the alternator but EXPECTING to deplete the battery
over the course of the "food warming time")

> Watts is watts.  No need to crank the volts up to run
> a resistor.
> Start with warm food and good insulation.

I think the problem lies with the period over which it
might want to be kept warm (warm enough to serve at an
enjoyable temperature?).  If you're hoping to set up a
"taco wagon" you'd have different concerns than if
you're just trying to keep something warm on the drive
to Grandma's house.

A neighbor built a "food vending van" and relied on
a genset located in a rear compartment (no path for
fumes to enter the van) for all his power needs.
But, his intent was only to power things while PARKED
(not while riding down the road).

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