That's the way I was leaning. The part that gave me pause is that the
heat gun on a wall outlet (not on the inverter) gives me 560W instead of
355W. About the same VA either way. I would question the measurement
except the fan is audibly weaker when the heat gun is on the inverter.
Why is less work performed when the same device is on the inverter?
Does the low power factor indicate an inefficiency that needs to be
accounted for on the DC side?
------ Original Message ------
From: "Zach Underwood" <[email protected]>
To: [email protected]
Sent: 1/25/2018 11:00:23 AM
Subject: Re: [AFMUG] Watts and VA on DC vs AC
335W/12v= 29.58 amps at 12volts
1AC watt = 1DC watt
On Thu, Jan 25, 2018 at 10:49 AM, Adam Moffett <[email protected]>
wrote:
I wanted to rig up a load test for some batteries.
I don't have a substantial 12V DC load, so I set up a 1000W inverter,
a short extension cord, a Kill-a-Watt meter, and a heat gun.
With the heat gun on low, The kill-a-watt reads 110v, 606 VA
<https://maps.google.com/?q=110v,+606+VA&entry=gmail&source=g>, and
355W.
The question is how much load is this putting on the battery?
Somewhere between 30 and 60amp I guess, and either way my multimeter
can't measure more than 10A DC current, so I can't measure it
directly.
My Googling on the topic has failed to enlighten me. My instinct is
to think that Watts is Watts, so I should probably use 355W in my
calculation of battery capacity, but I'm not sure.
--
Zach Underwood (RHCE,RHCSA,RHCT,UACA)
My website <http://zachunderwood.me>
advance-networking.com
