LED definitions for the SPX Wellhead can be found in separate User Guides for SDI-12 and MODBUS.
The AquaVent Wellheads have a multicolour LED light which indicates the status and operation of the AquaVent:
Fast Multicolour cycle 3 times: Wellhead is powering-on
Fast 10 cycles alternating blue/green: Wellhead has successfully connected to the PC using the USB
Fast 10 cycles alternating blue/red: USB connection has been dropped
Flashing yellow: The Wellhead is communicating with the PC Software over USB