XLINK 500/100 Operations & Maintenance Manual page # 22
4.3.
Earth Ground Point
A connection point has been provided for an Earth ground. Always connect the earth ground to
a suitable ground at the site as described below.
Any time a sensor cable is attached to the terminal strip, the unit may be exposed to electrical
surges such as those that come from nearby lightning strikes. The unit includes spark gaps and
other protection devices that shunt the energy to the earth ground. If there is no connection to
the earth ground point, the energy has nowhere to go, and the unit can be damaged.
Failure to properly connect the Earth ground point will lead to failures in the field due to
surges.
To install a proper ground connection point:
Use a copper ground rod driven into the ground at least 6 feet.
Attach a very heavy gauge (#4 Solid Copper) wire between the rod and the Earth ground
point on the unit. The connection point can accept up to a 4-gauge solid copper wire. If
a heavier gauge copper wire is used to connect to the ground rod, a reducer may be
necessary to connect to the terminal on the unit.
Firmly secure the screw on the ground point firmly on the copper wire. Do not rely on AC
power ground connections as they are not always properly grounded and may introduce other
surges.
Gas tube protection exists on the following inputs, based on the model:
XLINK 500
SDI-12
RS-485
DIN1 and DIN2
DOUT
VREF
Analog A
Analog B
Analog Diff C
Analog Diff D
4-20mA
XLINK 100
SDI-12
RS-485
