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CHAPTER 3: Installation
3.1.2 F
RAME
G
ROUND
/S
IGNAL
G
ROUND
Jumper W7 ties signal ground to frame ground. The position is left open at
the factory. If signal ground is to be connected to frame ground, solder a
100-ohm, 1/2-watt resistor in location W7. A wire jumper may also be used.
Care must be taken to ensure that ground circulating currents are limited
to acceptable levels.
3.1.3 H
ALF
/F
ULL
-D
UPLEX
O
PERATION
Jumper W8 selects half-duplex or full-duplex operation. Set W8 to the HALF
position for half-duplex operation. Set W8 to the FULL position for full-
duplex operation.
NOTE
When the jumper W9 is in the ON position and jumper W15 is in the A-B
position, the RS-485 driver is always turned on to enable transmission of
data. Therefore, half-duplex transmission cannot be performed. See
Section 3.1.5 for an explanation of the RS-485 driver.