Scanivalve ZOC 33/64Px, Инструкция по эксплуатации и обслуживанию

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ZOC33
Section 4: Electronic Components
Multiplexer Board
Each eight (8) channel sensor pack has its own combina -
tion multiplexer and excitation board. The board consists
of a precision voltage regulator, eight sensor mounts, and
a multiplexer. The board is installed on the sensor housing
(Figure 3.8).
The board is powered by ±15Vdc. This voltage must be
regulated, but does not need to be “instrumentation qual -
ity”. The precision voltage regulator is an LT1021 which
converts the ±15Vdc to a precision 5.00Vdc. The LT1021 has
a very tight output voltage tolerance and a very low tem -
perature coefficient. The output of the LT1021 is used as an
excitation voltage for the sensors.
The multiplexer receives millivolt input signals from each of
the sensors. It also receives inputs from the decoder board
which select the channel to be output to the amplifier
board. The multiplexer is a DG507. It has a settling time of
400 nanoseconds.
The Multiplexer board plugs into the decoder board.
Figure 4.3 - ZOC33 Multiplexer Board Schematic