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Bill George
09-05-2014, 1:12 PM
I've got a Watts Up Pro digital recording wattmeter coming. Can I measure tube wattage by measuring the input of the 120 volt laser tube power supply and be accurate enough?

I can download to a laptop via USB and into Excel to get a graph of the input wattage to the PS.

Dan Hintz
09-05-2014, 1:51 PM
Define "accurate enough". You could likely get within +/-20% without a problem. Anything tighter and you'd need to know how efficient your power supply is.

Clark Pace
09-05-2014, 1:51 PM
Not sure what this is,but I got a 100 watt tube tester for about $60 on ebay.

Kevin Gregerson
09-05-2014, 2:39 PM
Take it out of focus, fire away. Power loss comes from optics and tube.

Bill George
09-05-2014, 2:40 PM
Tube as Laser tube? I would wonder how it works on the HV output and measuring milliamps or on the input, mine is 120 volt.
I have an very nice RMS reading Fluke clamp on amp meter but I would never use on the output of the PS. Also have a Fluke DVM that could be used inline to the input of the PS. But V x A is not true wattage as it does not consider the power factor. Its only valid for a resistive load.

Quick eBay search shows no laser tube watt meters, maybe I missed something? I did find one for $99 but it says 1 volt input, just wondering what a "real" laser watt meter looks like?

Dan Hintz
09-05-2014, 7:33 PM
Quick eBay search shows no laser tube watt meters, maybe I missed something? I did find one for $99 but it says 1 volt input, just wondering what a "real" laser watt meter looks like?

You're looking for a Power Wizard... $800 new, I managed to find one on eBay years back for half of that.