Octagon PC-510, User Manual

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PC-510 user’s manual Notice to user
IMPORTANT!
Please read the following section before installing your product:
Octagon’s products are designed to be high in performance while consuming
very little power. In order to maintain this advantage, CMOS circuitry is
used.
CMOS chips have specific needs and some special requirements that the user
must be aware of. Read the following to help avoid damage to your card from
the use of CMOS chips.
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Using CMOS circuitry in industrial control
Industrial computers originally used LSTTL circuits. Because many PC
components are used in laptop computers, IC manufacturers are exclu-
sively using CMOS technology. Both TTL and CMOS have failure
mechanisms, but they are different. Described below are some of the
failures which are common to all manufacturers of CMOS equipment.
However, much of the information has been put in the context of the
Micro PC.
Octagon has developed a reliable database of customer-induced, field
failures. The average MTBF of Micro PC cards exceeds 11 years, yet
there are failures. Most failures have been identified as customer-
induced, but there is a small percentage that cannot be identified. As
expected, virtually all the failures occur when bringing up the first
system. On subsequent systems, the failure rate drops dramatically.
n Approximately 20% of the returned cards are problem-free. These
cards, typically, have the wrong jumper settings or the customer has
problems with the software. This causes frustration for the cus-
tomer and incurs a testing charge from Octagon.
n Of the remaining 80% of the cards, 90% of these cards fail due to
customer misuse and accident. Customers often cannot pinpoint the
cause of the misuse.
n Therefore, 72% of the returned cards are damaged through some
type of misuse. Of the remaining 8%, Octagon is unable to deter-
mine the cause of the failure and repairs these cards at no charge if
they are under warranty.