Jumpers and connectors, Jumpers—a general explanation, System board jumpers – Dell PowerEdge 1750 User Manual
Page 15: Jumpers
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Jumpers and Connectors
Dell™ PowerEdge™ 1750 Systems Service Manual
SCSI Backplane Board Connectors
This section provides specific information about the jumpers on the system board. It also provides some basic information on jumpers and switches and
describes the connectors and sockets on the various boards in the system.
Jumpers—A General Explanation
Jumpers provide a convenient and reversible way of reconfiguring the circuitry on a printed circuit board. When reconfiguring the system, you may need to
change jumper settings on the system board. You may also need to change jumper settings on expansion cards or drives.
Jumpers
Jumpers are small blocks on a circuit board with two or more pins emerging from them. Plastic plugs containing a wire fit down over the pins. The wire
connects the pins and creates a circuit. To change a jumper setting, pull the plug off its pin(s) and carefully fit it down onto the pin(s) indicated.
shows an example of a jumper.
Figure 5-1. Example Jumper
A jumper is referred to as open or unjumpered when the plug is pushed down over only one pin or if there is no plug at all. When the plug is pushed down
over two pins, the jumper is referred to as jumpered. The jumper setting is often shown in text as two numbers, such as 1-2. The number 1 is printed on the
circuit board so that you can identify each pin number based on the location of pin 1.
System Board Jumpers
shows the location and default settings of the jumper blocks on the system board. See
for the designations, default settings, and
functions of the system's jumpers.
Figure 5-2. System Board Jumpers
CAUTION:
Make sure the system is turned off before you change a jumper setting. Otherwise, damage to the system or unpredictable results may
occur.