Hardy HI 2204LT Weight Transmitter - Manual (Page 10)

HI 2201LT/HI 2204LT
6
FIG. 4 OUTPUT/POWER LOOP WIRING
NOTE: Be sure to shield the tie point for CE compliance.
Earth Ground and
Signal Return “Earth Ground” is used here to indicate a point actu-
ally connected to a path into the Earth’s ground. The
term “signal return” is used to indicate a return path
for signals to the negative side of the power supply, or
in the case of the output/loop, signal return means the
more negative side of the voltage being measured.
(See Figs. 4 & 5)
FIG. 5 TYPICAL SYSTEM WIRING WITH ISOLATION
NOTE: Be sure to shield the tie point for CE compliance.
Receivers may be inserted into the minus or the plus
power supply/transmitter path, or both. It is not neces-
sary that one of the transmitter output leads be con-
nected directly to ground.
Appropriate grounding and shielding helps to protect
the signals from noise. However, it may be necessary
to try various ground/shield configurations to find the
best one for a particular installation. Figures 4 & 5 are
examples only.
The transducer cable shield should be connected to
either the earth ground or the signal return, on the
input side of the transmitter to protect against noise,
but not to both. The recommended configuration con-
sists of the transducer cable shield connected to the
output/power cable shield and to the signal return.
DC
Power
Supply
+
Loop Powered Level
Weight Transmitter
+ Isolator
+
+
Relays
Set
Point
RCVR
+
RCVR
+
110
VAC
110
VAC
110
VAC
110
VAC