SGND & FRGND (JB4)
In the connected position, this strap links Signal Ground and
frame ground through a 100 ohm resistor. In the open position, signal
ground is disconnected from frame ground.
JB4
Position 1&2 = SGND and FRGND Connected
Position 2&3 = SGND and FRGND Not Connected
3.3.3 Model 1001RCM11545& 1001RCM115TB Strap Settings
Figure 9 shows strap locations for the Model 1001RCM115XX (DB-
15) rear cards. These straps determine various grounding characteris-
tics for the terminal interface and twisted pair lines. JB3 and JB4 are
user configurable.
The table below provides an overview of interface strap functions
for the rear interface cards. Following the table overview are detailed
descriptions of each strap’s function.
17
DTE Shield (DB-15 Pin 1) & FRGND (JB3)
In the connected position, this strap links DB-15 pin 1 & frame
ground. In the open position, pin 1 is disconnected from frame ground.
JB3
Position 1&2 = DTE Shield (Pin 1) and FRGND Connected
Position 2&3 = DTE Shield (Pin 1) and FRGND Not Connected
SGND & FRGND (JB4)
In the connected position, this strap links DB-15 pin 8 (Signal
Ground) and frame ground through a 100 ohm resistor. In the open
position, pin 8 is connected directly to frame ground.
JB4
Position 1&2 = SGND (Pin 8) and FRGND Connected through
a 100 ohm resistor
Position 2&3 = SGND (Pin 8) and FRGND Directly Connected
18
1 2 3
JB3
JB4
1 2 3
Figure 9. 1001RCM115XX strap locations
INTERFACE CARD STRAP SUMMARY TABLE #3
Strap
Function
Position 1&2
Position 2&3
JB3
DTE Shield (Pin1) & FRGND
Connected
Open*
JB4
FRGND & SGND (Pin 8)
Connected
Open*
* Indicates default setting
