Keithley PIO-96, Instruction Manual

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2-10 Installation PIO-96 User’s Manual
Wiring PIO-96 power to external circuits
External power from the computer’s internal supply is available on the PIO-96 connector. This
power is convenient to use for common board applications. However, Keithley recommends that
you do not use the computer power unless you are confident that you can safely meet the follow-
ing conditions.
• There must be no short circuits, overloads, or application of external voltages. All of these
conditions may damage the computer system board and result in costly repairs. The com-
puter power supply is designed to shutdown on a short circuit, but you should not rely on this
characteristic.
•
The amount of power drawn must be consistent with the capacity of the computer power
supply and its internal loads (see your computer’s technical reference manual). Due to com-
puter board connector and trace-width limitations, the manufacturer recommends that you
limit power draw to 1 ampere regardless of power supply capabilities.
In situations where the PIO-96 is used with a dedicated peripheral (for example, a switch pad)
and the cabling and design loads are fixed, it may make economic sense to use the PIO-96 power
outputs. In most other cases, it is advisable to power external devices from their own supplies.