New to smoking Question on How much wood chips to use.

Thanks all for the replies. After closer look at the blackened chips, they do seem to be intact. I thinks that's caused me to be believe they were done. In addition may not have had the chip unit seated properly in the smoker as I changed out he chips when things were hot and I had no way to handle the chip unit safely. A pair of good cooking gloves is in order I guess. 

Even though the smoker interior temp stayed at recommended 225 degrees for over 6 hours( 3 lb loin), I never could get pork loin temp above 164, so finished it in the oven. Outdoor temp was cool in the late 30s and early forties all day. Does that affect smoker temp, even though interior temp of the unit was 225 to 250 the entire time?

I have a separate thermometer I use to measure the inside temp, as the unit only shows temp set and not actual temp. That said, the standalone thermometer itself needs to be calibrated perhaps. Ill check in my stove's oven, 

Thanks