Small LCD power consumption test

I bought an 17 inch ViewSonic VG712s LCD from local auction site. It didn't have an power adapter and there was no guarantee abut it working, but 10€ didn't seem much. After the arrival I read that it needs 12V@3.42A. Well, lucky me, I just happen to have 12V electrical system for my lab and an 12V 10A switching regulator powering it. After a bit of testing it came out that 12V means 12V, not 11.5V, had to make decent wiring to it to get rid of voltage drop. Because I try to power my 12V system from renewable energy sources when possible (I have 30W solar panel that powers it in the summer), it woult be nice to know how much power it draws and how it reacts to different states. So here is what I measured at 12V:

Lowest brightness, white screen: 1.662A

Lowest brightness, black screen: 1.768A

Highest brightness, white screen: 2.964A

Highest brightness, black screen: 3.051A

In sleep mode: 26mA

Turned off: 16mA

Couple of fun facts.. LCD takes less power with white screen on it.. weird. Also, there is no point of turning it off, because the difference is 10mA.. I guess that this power goes to powering the led on the front..

One thought on “Small LCD power consumption test

  1. It is not weird that white screen takes less current. Black screen means that the crystals all have to be exited in to non lucent state while white means that no power is needed since lucent is normal state.

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