Clamp amp meter or Kill-A-Watt meter

CBehr · 01/28/2009, 10:49 AM

I want to figure out the exact $$ my system is costing me a month. I read a nice article on usuing a clamp amp meter and a patch cord. Is this necessary or do the kill-a-watt meters by P3 do the same exact thing?

I don't really understand all the conversions from amps/voltage/watts etc.

JNye · 01/28/2009, 04:13 PM

the P3 is all you need. To get an accurate measure I think its best to leave it one each appliance for at least a full day and record the KWHs used. But you could quickly check everything in watts and then plug in the watt numbers on the electricity calculator on the RC homepage with your local elecrtic rates.

dvanacker · 01/28/2009, 07:02 PM

Voltage x amperage = watts

watts / voltage = amperage

watts / amperage = volts

grigsy · 01/28/2009, 09:25 PM

I can't speak for the P3, but I do use the Kill-a-watt meter and I really like it. It's a great device.

I find myself checking out more than just the aquarium - including the electrical draw of the TV, the iron, microwave, house lights, etc. It convinced me to use only compact fluorescents for my house lighting.

RokleM · 01/29/2009, 09:30 AM

Quote:

Originally posted by grigsy
I can't speak for the P3, but I do use the Kill-a-watt meter and I really like it. It's a great device.

I find myself checking out more than just the aquarium - including the electrical draw of the TV, the iron, microwave, house lights, etc. It convinced me to use only compact fluorescents for my house lighting.

I agree on the kill-a-watt, but not the CF bulbs. That will start a war

dean1977 · 01/29/2009, 08:55 PM

Kill-a-watt is the greatest thing. I pay 30$ a month for the TV!

MSX-Jeff · 01/29/2009, 10:43 PM

For most things aquarium related, the kill-a-watt is a better option than the meter. You can easily come up with VA wattage (volts x amps = watts)...however, pumps and lights will need to have the power factor of the device figured in to determine RMS wattage (what you pay for). PF is not easy to determine...in comes the kill-a-watt, it will give you VA "watts", RMS wattage, power factor, volts, amps, and KwH's. Probably the best $30 I've spent on my tank

BTW, a kill-a-watt is an ABSOLUTE MUST for folks who like to tinker with aspirating NW pumps for protein skimmers. Low power factor is often encountered and can lead to premature pump failure.

Icefire · 01/29/2009, 10:51 PM

MSX-Jeff at least here we don't pay for VAr, only Watts so a meter is enought.

MSX-Jeff · 01/29/2009, 10:58 PM

Quote:

Originally posted by Icefire
MSX-Jeff at least here we don't pay for VAr, only Watts so a meter is enought.

That is the same as in the states...you pay for "watts", which is actually RMS wattage.

example:

You have a pump that is rated for 50w. that pump has a PF of .50. If you just use a clamp on meter and do the math you will freak out when your math comes up with a wattage of 100w. When you plug the same pump into your kill-a-watt, the wattage reads 50w (the true RMS wattage), which is VA x PF = RMS watts (what you pay for)

CBehr · 01/30/2009, 06:28 AM

Quote:

Originally posted by dean1977
Kill-a-watt is the greatest thing. I pay 30$ a month for the TV!

Are you serious!? What size TV is that and is it running 24/7?

01/28/2009, 10:49 AM	#1
CBehr Registered Member Join Date: Nov 2007 Location: Ephrata, PA Posts: 588	Clamp amp meter or Kill-A-Watt meter I want to figure out the exact $$ my system is costing me a month. I read a nice article on usuing a clamp amp meter and a patch cord. Is this necessary or do the kill-a-watt meters by P3 do the same exact thing? I don't really understand all the conversions from amps/voltage/watts etc. __________________ 1st time w/o a tank in 10+ years. Planning 65g..mainly fish, maybe a few LPS/Softies

01/28/2009, 04:13 PM	#2
JNye Moved On Up Join Date: Feb 2007 Location: Lansing, IL Posts: 2,230	the P3 is all you need. To get an accurate measure I think its best to leave it one each appliance for at least a full day and record the KWHs used. But you could quickly check everything in watts and then plug in the watt numbers on the electricity calculator on the RC homepage with your local elecrtic rates. __________________ Joe Current Tank Info: it don't matter just don't bite it

01/28/2009, 07:02 PM	#3
dvanacker DID I SOUNDS SMRT?? Join Date: Aug 2005 Location: Ontario, CAN Posts: 3,690	Voltage x amperage = watts watts / voltage = amperage watts / amperage = volts __________________ --DARRYL-- Current Tank Info: 200g SPS dominant Mixed Reef

01/29/2009, 10:51 PM	#8
Icefire Seasoned reefer Join Date: Jan 2007 Location: In Quebec, Canada Posts: 3,653	MSX-Jeff at least here we don't pay for VAr, only Watts so a meter is enought. __________________ Temp 80F, PH 8.5-8.0, Alk 6.8-7.2, Ca 430, Mg 1700, NO3 0-0.25, PO4 0.04, 34.4 PPT Lights @ 100% all others, 35% White Current Tank Info: 60g Cube, 120lbs live rocks, Hydra52 2x120W, 2 MP40+ 1 MP10 @ 70%, Phosban 550 GFO+Carbon, 200W Heater, SWC Skimmer, Kalk ATO, 150 gpd RODI

01/28/2009, 09:25 PM	#4
grigsy Registered Member Join Date: Sep 2003 Location: Santa Cruz, CA Posts: 2,307	I can't speak for the P3, but I do use the Kill-a-watt meter and I really like it. It's a great device. I find myself checking out more than just the aquarium - including the electrical draw of the TV, the iron, microwave, house lights, etc. It convinced me to use only compact fluorescents for my house lighting.

01/29/2009, 08:55 PM	#6
dean1977 Registered Member Join Date: Feb 2004 Location: south jersey Posts: 535	Kill-a-watt is the greatest thing. I pay 30$ a month for the TV!

01/29/2009, 10:43 PM	#7
MSX-Jeff Registered Member Join Date: Dec 2008 Location: On the Web Posts: 319	For most things aquarium related, the kill-a-watt is a better option than the meter. You can easily come up with VA wattage (volts x amps = watts)...however, pumps and lights will need to have the power factor of the device figured in to determine RMS wattage (what you pay for). PF is not easy to determine...in comes the kill-a-watt, it will give you VA "watts", RMS wattage, power factor, volts, amps, and KwH's. Probably the best $30 I've spent on my tank BTW, a kill-a-watt is an ABSOLUTE MUST for folks who like to tinker with aspirating NW pumps for protein skimmers. Low power factor is often encountered and can lead to premature pump failure.