ICS PCI-WDT 500, Product Manual

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Manual Number: 00650-144-1 Page 11
Chapter 3: Option Selection
Refer to the Block diagram on the previous page and the Option selection map when reading this
section of the manual. Card operation is determined by jumper installation as described in the
following paragraphs.
Relay Enable/Disable
Hold the card with the fingers at the bottom and the mounting bracket on the left. The relay-control
jumper is located alongside the relay at the left-hand side of the card. If no jumper is placed on the
block, the relay is always de-energized. If a jumper is placed between the two left-hand posts, the
relay is always energized when +5V power is on. And, if a jumper is placed between the two right-
hand posts, the relay is energized during reset (watchdog timeout). If you desire to use the relay
output, then the jumper should be placed between the right-hand posts.
Screw Terminals
Screw terminals located on the right-hand side of the card provide the means for connections of the
watchdog output to points inside the computer chassis. The top terminal provides the active-low
watchdog output. The next terminal provides a ground. The third terminal provides the comple-
mentary active-high of the first terminal output. The fourth terminal down provides power to the
computer fan and the fifth terminal from the top provides pulse-width modulated control for fan
speed. The bottom terminal is inputs from the computer’s fan. If the fan stops, this input can signal
that the system should be shut down.