NorPak???
Reid Allen
Reid.Allen at eni.com
Mon Nov 17 10:29:07 CST 2008
Norpak was a logic device that used only 'NOR' gates. It preceded the PLC concept. The gates were hardwired. Since any logic function can be created using negative Boolean operators (NOR or NAND) they were usable for solid state control systems in place of relays. We used a Norpak system at the San Francisco International Airport on a plane fueling system in the middle 1960s. They had 10 NOR gates per module, and we wired modules using something like #20 AWG wires with some kind of termination on the end that could be inserted into the Norpak units.
One had to be very careful using the units because after the various functions and their arrangement had been designed there were often redundant gates in series that could be eliminated, but this caused transparency of design to be lost.
I was working for the Standard Oil Company of California in those days down on 225 Bush Street.
Reid C. Allen, P.E.
Roberts & Schaefer
10150 South Centennial Parkway #400
Sandy, Utah 84070
Reid.Allen at eni.com
Tel: 801.984.0900 Ext. 210
Fax: 801.984.0909
Cell: 801.634.5640
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