Ground Connections; Usb Connection - Observator Instruments OMC-048 Hardware Manual

3.2 Ground connections

- The negative input power connection (terminal 1) is filtered and therefore not equal to ground!
- The analogue ground is decoupled so not equal to ground!
- The SDI-12 ground is dedicated to the SDI 12 input.
Basic ground connection rule:
Use the ground (GND) and signal connections within same section (= white lined box) and
you will be fine!

3.3 USB connection

The logger can be powered via the USB connection for configuration & firmware updates.
However, your USB port might not supply enough power when sensors are connected and / or the modem
is active.
Therefore the logger application will not start when no external power is present!
External power (12-24VDC) is required for running the logger application!
The OMC-048 Scriptable Data Logger will create 2 connections with your PC:
1. Mass Storage device
2. USB Serial device (Com port)
The OMC-048 will check for a USB connection every 10s.
Users' Hardware Manual | OMC-048
Status:Released | Not confidential
Page 12 | 15
V1.4