Hi, I've got a product development project going and at this stage I need to be able to monitor and record the watts or kw-hours of a commercial refrigeration unit (similar to the open-face refrigerators you would find in your local grocer). Unfortunately, neither myself or the other engineering student in the group have any real electrical experience. The problem that we seem to be running into is finding a power meter with data logging capabilities that can connect to the higher voltage/amperage of the power supply and the physical plug and receptacle that the unit uses. The solution also has to be relatively inexpensive, as our budget is very limited. The plug out of the fridge is a L14-20P (125/250V, 20A) which connects into a matching L14-20R. The affordable units that do what we need all use three-wire adapters and we have been warned away from trying to wire the 4-wire L14-20 into a 3-wire. I'm pretty stumped at this point. I need to be able to monitor the unit continuously for several days, while it records watt readings, and then download the data to my laptop for analysis. If anyone has an idea for a solution, or even just some suggestions on what direction to go in, what to read, etc., I would really appreciate it. Thanks and cheers.