At Summit station we are using National Meter Industries, Inc. K4000 and KW4000 series meters, mostly the K4240.

• http://www.national-meter.com/
• Technical contact: Don, 800.325.6674, New Hampshire
• Accuracy: The CTs are +/- 1% between 4 - 400 AMPS, +/- 3% below 4 AMPS and starts sending a signal to the meter at +/- 65 watts.

One uses the 34.exe Windows program to change their RS-485 address, however this program will only work through COM1 or COM2. One must use the 1A PowerStudio? program (which National normally sells) if addressing a higher COM port.