Mechanics of the Power1401-3
Earthing
All metallic parts of the Power1401 enclosure are earthed. The
inner can is tied to the earth rail of the circuit board via the
screws that fix the board to the inner-can tray. The outer case is
wired to the earth rail by eyelets screwed to the outer-case
metalwork. Expansion daughterboards are earthed via the brass
spacer pillars. Earth continuity throughout the enclosure is
ensured by metal-to-metal contact where parts are screwed
together. There is a threaded M3 earth stud on the rear panel,
for the earthing of auxiliary equipment. The Power1401 earth
rail is connected to mains earth via the DC power socket and
the earth leads of the power supply.
Upgrade by
users
For most kinds of daughterboard it is feasible for a user to
expand a Power1401 in the field, though we do prefer units to
be sent back to CED. No particular electronic expertise is
required; the task should be well within the capability of an
averagely practical person. Normal precautions against
electrostatic discharge need to be taken. The expansion kit is
quite economical since all parts of the unexpanded enclosure
are reused apart from the inner-can lid. Detailed instructions are
included in any expansion kit sent out to customers (as is a
2mm hex driver for the rear-panel screws). Opening a
Power1401 is described on the following page.
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Summary of Contents for Power1401-3
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