measure Watts consumed

**hifiguy** · 05-17-2004, 05:32 AM

This tool will finally answer everyone's question:

"Is 150W enough to power my system?"

These guys make a product called Watts Up? and it allows people to instantly measure how many Watts are being consumed by any 120V device. You simply plug this inbetween the source and the device and it reads out the power used, cost, and a bunch of other nice facts.

They have two versions, the regular and the Pro which has a serial connection to transfer data to your PC about power consumed over a period of time. The price is a bit steep but I think it will aleviate everyone's fear of whether 150W will be sufficient to power their PC rigs.

Anyone used one of these before? If I end up buying one I'll post some results.

**weekendowel** · 05-17-2004, 07:20 AM

I have a similar thing but for 230 V instead (for use in Europe). It works very well. I use it to monitor how much energy are used in various battery based installations at my work.

**DavidL** · 05-17-2004, 11:12 AM

Isn't a power supply rated on how many watts it "outputs", vs. "consumes"? So, with this device, one would use an estimation of Power supply efficiency to determine output wattage? Use 70% if no other info is available?

**god_of_cpu** · 05-17-2004, 11:38 AM

Damn, yo $100... Just get yourself a good multimeter like this one for < $20 that will measure amps. To get wattage, just multiply by voltage. That one will be good up to 10 amps*12v = 120 watts. For a bit more you can get thisone that goes to 20 amps.

**NewTechFool** · 05-17-2004, 02:44 PM

Yes, you need to keep the efficiency of the PSU in mind when measuring the input Watts, and the efficiency varies with the load.

For measuring the input Wattage I love the Kill-A-Watt. It does volts, hz, amps, VA, Watts, kWh etc.

It is an excellent tool. Check the power consumption of that old fridge/freezer in the garage. You will be surprised!

http://froogle.google.com/froogle?q=...b=ff&scoring=p

**hifiguy** · 06-12-2004, 05:46 PM

i convinced my work to get me the Watts-Up? tool so I've posted a few preliminary readings on my site.

My desktop consists of:

Enermax 350W FCA
XP1900
MSI Turbo2
1GB SDRAM
MSI FX5600
M-audio 7.1 PCI
Netgear 10/100 NIC
Samsung 52x CDR/CDRW/DVD-ROM
Maxtor 60GB 7200 2MB
Maxtor 250GB 7200 8MB
NewQ Platinum

The average idle reading was 149W into the PSU. More readings to follow!

**beaverpants** · 06-13-2004, 02:27 PM

big problem is thats what the PSU DRAW's. and ATX one's are not vary efficent. so lets say you need 120w to run your system. and its drawing 120w. the ATX PSU lets say a 300w one. it might be drawing 200w since its only 70% efficent

**kandyman676** · 06-13-2004, 02:42 PM

the only problem i have @ Watts Up is it is all AC current measurements. however, its benefit is the data capturing via the serial port.

too bad they don't make one for DC applications.

**hifiguy** · 06-16-2004, 02:34 AM

Test 1: 76W average into Enermax 350W PSU

MicroATX MSI KM4M
Duron 1.6 .13um
80mm Thermaltake Smart Fan
512 2700 Micron DDR
WD 80 7200 8mb
Pioneer 16x DVD-ROM
3COM PCI 11a/b/g

-------------------------------
Test 2: 101W average
Added 8x AGP MSI FX5600

-------------------------------
Test 3: 2W average
Removed AGP and placed PC in Hibernate

-------------------------------
Test 4: Standby Mode
So I put my PC on standby in the middle of playing an mp3 and found the following:

Watts consumed: 35
CPU remains on
Wifi pci remains on
USB 2.0 hub remains on
Mouse LED remains on

Coming back from standby took under 1 second (freshly formatted machine) and music continued to play even before Lilliput came on!

If it wasn't for the 35W drain I'd definitely used Standby over Hibernate.