The "-L" on a product model indicates that the cable length is specified at the time of order.
The 03001 Wind Sentry Set was replaced with the 03002 Wind Sentry Set on January 9, 2009. The 03001 and 03002 use the same vane and anemometer. However the 03002 includes a junction box allowing one cable to connect the entire wind set to the datalogger. The retired 03001 used two cables—one for the anemometer and one for the wind vane.
The anemometer is measured by the PulseCount instruction in CRBasic, and by Instruction 3 (Pulse Count) in Edlog. The wind vane is measured by the BrHalf Instruction in CRBasic, and by Instruction 4 (Excite-Delay-SE) in Edlog. The measurements are typically processed for output with the Wind Vector Instruction (not present in the CR500 or CR9000).
The 03001's anemometer consumes one pulse count channel on the datalogger. The Wind Vane requires one single-ended channel and access to an excitation channel (the excitation channel can be shared with other high impedance sensors).