Anyone here know i would go about testing the draw of a LED grow light?

I have 1 LED grow light that I've had 6 months not that I suspect its loosing power but i'd like to test it, also like to know how to test it for when I get another.

Getcha one of these

https://www.amazon.com/P3-P4400-Electricity-Usage-Monitor/dp/B00009MDBU/ref=mp_s_a_1_2?ie=UTF8&qid=1540054405&sr=8-2&pi=AC_SX236_SY340_FMwebp_QL65&keywords=killawatt&dpPl=1&dpID=41jXOUcM37L&ref=plSrch

Badmofo529 said:

Getcha one of these

https://www.amazon.com/P3-P4400-Electricity-Usage-Monitor/dp/B00009MDBU/ref=mp_s_a_1_2?ie=UTF8&qid=1540054405&sr=8-2&pi=AC_SX236_SY340_FMwebp_QL65&keywords=killawatt&dpPl=1&dpID=41jXOUcM37L&ref=plSrch

Click to expand...

Cool thanks.