M
Martin Riddle
- Jan 1, 1970
- 0
Has anyone have experience with something like this?
http://www.ndaenergy.com/power-factor-benefits.html
http://www.ndaenergy.com/power-factor-benefits.html
Martin Riddle said:Has anyone have experience with something like this?
http://www.ndaenergy.com/power-factor-benefits.html
Martin said:Has anyone have experience with something like this?
http://www.ndaenergy.com/power-factor-benefits.html
Cydrome said:In short, it's a scam.
there is some truth behind power factor correction saving power,
but it's not 10 to the totaly bogus 25% savings they claim.
Has anyone have experience with something like this?
http://www.ndaenergy.com/power-factor-benefits.html
Has anyone have experience with something like this?
http://www.ndaenergy.com/power-factor-benefits.html
That old fraud again.
In a very simplified nutshell, a load with a power factor less than 1 draws
both real power and "wattless" or reactive power. "wattless power" seems like
a contradiction but its the slang used in the power industry. Wattless amps
flow out of phase with the voltage waveform and are caused (usually) by loads
that have an inductive component (electric motors, primarily) or (rarely) by
loads with capacitive components (un-PF corrected switchmode power supplies,
some types of fluorescent lights, etc.) The real amps and the wattless amps
add quadratically to produce the total amps.
[snip]
The only other common situation where correcting a low PF load makes sense is
when you're trying to run the load from a generator that is being overloaded
by the wattless current. We touched on that yesterday in another thread. In
this instance, correcting the PF of the low PF furnace blower will allow the
generator to handle the load AND power some other loads. It will also save
fuel so if you're off-grid or experience frequent power outages, PF correction
might be worthwhile, depending on your existing PF and how often you run your
generator. [snip]
If there is a lot of interest in this then I'll do a web page on DIY PF
correction. However, unless you have a special circumstance such as those
listed above, it's simply not worth the effort. It would take years for the
tiny power savings to pay back the cost of even $100 worth of capacitors.
John
I would appreciate info on power correction to reduce load on the
emergency generator when powering the furnace blower - less load =
less gas = fewer trips outside in the cold to refill.
Jim said:If you can plug it into a Kill-A-Watt it will show you true Watts, VA
(Volt-Amps) and PF (Power Factor). Power factor correction will raise
PF towards 1.0 and reduce the VA closer to the Watts.
Jim said:A bad power factor is somewhat like bad shock absorbers when driving
down a bumpy road. The vehicle bounces up and down more than the road
does. With a poor power factor some of the electric current bounces
back from the motor.
I was following you until I got to this part.generator to handle the load AND power some other loads. It will also save
fuel so if you're off-grid or experience frequent power outages, PF correction
might be worthwhile,
It still won't affect your bill.
Oh, the furnace blower. He needs to measure that seperately but by the
sound of it would not know what to do with the data.
It could also be 'start-up current' that's causing the tripping. In which
case he needs more amps on the supply and a larger rated breaker. Or a
better designed blower.
Graham
stu said:I was following you until I got to this part.
I don't understand how PF correction would save much fuel. If the gererator
is loaded to maximum with a 0.50PF load, isn't still only generating the
REAL power?
Rather than willy-nilly placing caps acroos the motor windings,it
seems more reasonable to look for a rule-of-thumb based on motor
amperage/hp.
Other descriptions in the thread indicate that a smaller generator
could be used if PF is properly corrected. Being able to use a
smaller generator makes a difference in the fuel used.
I was following you until I got to this part.
I don't understand how PF correction would save much fuel. If the gererator
is loaded to maximum with a 0.50PF load, isn't still only generating the
REAL power?
I want to thank you for your replies on this subject. Having experienced
the PF problem on my little gen, I now understand (?) what is happening, and
why at a measured 300W, my little 850W generator sounded like it was running
flat out. I would like to put a vote in for a PF web page on your site.
But if not, at least now I can search to web to try to educate myself on how
to get the PF closer to 1.
As a side note, I just realized I have a poor copy of your cordless
battery charger as part of my emergency power arsenal. Found you on a search
for a 12v generator a few years ago.
Where the hell did (personal) generators come into this ? It's an entirely
different ball game.
Graham
About two-thirds of the way down in Neon John's initial post in this
thread.
Rob.....in Courtice said:I want to thank you for your replies on this subject. Having experienced
the PF problem on my little gen, I now understand (?) what is happening, and
why at a measured 300W, my little 850W generator sounded like it was running
flat out. I would like to put a vote in for a PF web page on your site.
But if not, at least now I can search to web to try to educate myself on how
to get the PF closer to 1.
Cydrome said:To approach unity power factor, you need to cancel out the extra
current drawn by your inductive load with capacitance.
You said your meter says the motor is using 300 watts. How many amps
is it drawing though?
The different between say 300watts/120 volts = 2.5 amps subtracted
from what the motor is really pulling will be what you want to cancel
out.
So say the motor pulls 4 amps, and you want to get it down to 3.
you need a capacitor or bank of caps that pull 1 amp of reactive
current.
At 120 volts as 60Hz, this is about 22uF per amp.
I would appreciate info on power correction to reduce load on the
emergency generator when powering the furnace blower - less load =
less gas = fewer trips outside in the cold to refill.