Black Box ME759C-RJ45 Cable Box User Manual


 
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CHAPTER 3: Configuration
Serial Interface: DTE Shield (Pin 1) Connection to Frame Ground (JB3)
This jumper applies to the serial interface. In position 1 and 2, this jumper
links the Protective Ground (PGND) or “DTE Shield” lead (DB25 Pin 1 or 10-
pin RJ Pins 1 and 10) of the RS-232 line to the interface module’s frame
ground (FGND). When this jumper is in positions 2 and 3, the RS-232
Protective Ground on DB25 Pin 1 or RJ-45 Pins 1 and 10 is disconnected
(“lifted”) from frame ground.
JB5
Positions 1 and 2 = PGND and FGND Connected
Positions 2 and 3 = PGND and FGND Not Connected (default)
Serial Interface: Signal Ground and Frame Ground (JB4)
This jumper also applies to the serial interface. In position 1 and 2, this
jumper links the Signal Ground (SGND) lead (DB25 Pin 7 or 10-pin RJ
Pin 5) of the RS-232 line to the interface module’s frame ground (FGND).
When this jumper is in positions 2 and 3, RS-232 Signal Ground on DB25 Pin
7 or 10-pin RJ Pin 5 is disconnected (“lifted”) from frame ground.
JB5
Positions 1 and 2 = SGND and FGND Connected
Positions 2 and 3 = SGND and FGND Not Connected (default)