N
N Cook
- Jan 1, 1970
- 0
On industrial kit, matrixed 25 switches panel (but no CE key so for any
repeat bounce you have to re-enter parameters from the start) in a dirty
environment, used day in day out.
Buttons through pierced aluminium top cover engage with click switches in a
matrix
through a plastic sheet barrier. The protruding small nibs under the buttons
eventually punch through the plastic sheet, allowing grime in.
Suggested solutions / any other opinions or ranking of the following.
Clean up/ replace the existing panel then
cover the whole panel and surround with some sort of semi-moulded but
flexible covering as found over the till buttons in fast-food joints/ bars
etc.
Add plastic rings around each nib to decrease the punch through force.
Extend the switch lines to an external properly sealed/robust switch panel
and block off the original, problem here is shift function for doubling the
key functions would require legends specific to the shift function for
operator use as well as the basic 0 to 9 etc
Add small caps to the control lines which have 10K pullups to Vcc, going to
the PA terminals of Rockwell R6520A in/out interface chip
Any other possibles
repeat bounce you have to re-enter parameters from the start) in a dirty
environment, used day in day out.
Buttons through pierced aluminium top cover engage with click switches in a
matrix
through a plastic sheet barrier. The protruding small nibs under the buttons
eventually punch through the plastic sheet, allowing grime in.
Suggested solutions / any other opinions or ranking of the following.
Clean up/ replace the existing panel then
cover the whole panel and surround with some sort of semi-moulded but
flexible covering as found over the till buttons in fast-food joints/ bars
etc.
Add plastic rings around each nib to decrease the punch through force.
Extend the switch lines to an external properly sealed/robust switch panel
and block off the original, problem here is shift function for doubling the
key functions would require legends specific to the shift function for
operator use as well as the basic 0 to 9 etc
Add small caps to the control lines which have 10K pullups to Vcc, going to
the PA terminals of Rockwell R6520A in/out interface chip
Any other possibles