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Confidential
– Limited Distribution
TD100
T
X
1
T
X
2
R
X
2
R
X
1
Ground Rod/Plate
TD24/48PSU
(24 or 48VDC)
Ground Rod/Plate
SUM
SUM
SUM
SUM
SUMA
10
Ω Earth to
Ground resistance
Centered between SUMA
SUMA
Figure 11. System grounding
Power is provided to the sensor cables at the SUM. For Fail-Safe operation, DC power is
supplied independently to the TX and RX cables. Each processor collects its power over the
lead-in cables with a diode
“OR” arrangement so that one can withstand either an open or
shorted sensor cable failure.
Figure 12. TX and RX Lead-In Cables
Heat shrink secured ferrite beads
Color-coded cable ends