[RE-wrenches] power factor meter

[Matt Lafferty]

Hi Jay,

Take a look at the Fluke 125 Power Scope. It's about $1500. It looks like a
pretty sweet meter. I think it will do what you're looking for.
Multi-channel DVOM + AC Power + Power Factor + More. The clamp doesn't do DC
amps, so that's a bummer.

For higher-end things like this, I'm generally not afraid of used Fluke
gear. Unless it's really old and beat up, you can get it factory serviced
and calibrated pretty easily. (I've taken in 15 year old meters for factory
calibration at no charge. Twice I've even gotten new leads back with the
meter. Can't beat that! Other times I've paid a small charge for the
service. Never quite have figured out the formula. I think it has to do with
whether or not you bring donuts to the counter-man when you drop it off...)

Although not a true "o-scope", an old Fluke 41 or 43 Power Quality Analyzer
will do lots for you, including waveforms, AC Power & Power Factor,
Harmonics, Logging, VARS, etc. I believe these have both been replaced with
"new and improved" more expensive models, but you can still find them in
fine shape on Ebay and sometimes Craigslist. The 43 replaced the 41...
Better software, logging, and a few more features. I used to use both all
the time and they are great for field and shop work. Given my choice of the
two, I'd go with the 43. If I saw a 41 in good shape for under $500, I'd
grab it without batting an eye. I might blink a couple times at $750. These
meters don't do DC amps by the way. (If you are going to buy these meters
used, make sure you get the battery, charger, optical cable, and current
clamps with them at a mimimum! They originally came with some voltage leads
and clips and a case, too, but those can be replaced pretty cheap.) 

Although probably not kosher with certain list lurkers, you will have to
make up what I call a "3-way resistor bob" to do 3-Phase power & pf on a
3-wire system. If you're gonna do this kind of testing, make sure you use
resistors with high enough ohm & watt ratings. If you don't, it makes a
really loud BANG when it lets go and takes the sub-main with it...
Particularly embarrassing when you are on the 7th floor of a high-rise under
construction and half the power on the floor goes out during shakedown and
you thought you'd be a smart alec and wear a pink hardhat that day. It's a
long walk down to the basement to reset the breaker and nobody wants to ride
the elevator back up with a guy wearing a pink hardhat! (Yes, it really
happened, and yes, I still have the pink hardhat...) If you get this far,
I'd be happy to tell you (offlist) how to make up a 3-way resistor bob that
shouldn't go bang. 

The 43B info is here:
http://www.testequipmentdepot.com/fluke/powermeter/43b.htm  They want $2,330
for it new. I paid $2,700 for one 7 or 8 years ago. 

There are also a lot of pawn shops in my neighborhood that have some pretty
nice equipment from time to time. Let me know off list if you're interested
and I'd be happy to take a walk and see if there are any good deals on
high-end test equipment. (Open offer to Wrenches in general)

Another place to watch for high-end or utility grade test and data logging
gear is the surplus sale lists for utilities. These are also good sources
for other specialty gear that we don't use "every day" but is nice to have
and can make you some money. Underground locating equipment, large crimpers
& cable-splicing equipment, etc. I'm keeping my eyes open for a nice thermal
imaging camera, personally.

I've seen some deals that I wish I had a good excuse to take advantage of.
Momma says there are too many toys in my hammock. She wants to use the
thermal imaging camera herself, so that one is OK. Funny thing that
double-standard. Most utilities require you to register for their list so
you can bid and so they can notify you when stuff that matches what you sign
up for comes up.
 
PG&E is here:
http://www.pge.com/b2b/purchasing/buyingfrompge/investmentrecovery/ (nothing
really interesting this month unless you want a bunch of 6'ID concrete lined
steel pipe...)
SMUD is here:
https://usage.smud.org/EBSSExt/Default.aspx?SolDisplayType=BroadClass&SolBro
adClass=Surplus  (Currently no surplus sales pending)

Hope this is helpful to anyone that might be in the hunt for some of this
specialty gear.

Be safe!

Matt Lafferty
gilligan06 at gmail.com

Brother Jay says:

I'm looking to upgrade my meter selection.

I'm looking for a powerfactor meter and oscilloscope  to better help in
diagnostics of inverter/generator issues.

I've seen a pretty inexpensive hand held oscilloscope from Velleman  # HPS10
for $135, but its not a power factor rated.

Any other suggestions?