Scanivalve ZOC 33/64Px, Instruction And Service Manual

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13
ZOC33
Section 3: Installation & Operation
Calibration Valve Operation
As discussed in Section 2, Introduction, ZOC33/64Px and
ZOC33/64PxX2 modules are equipped with an internal
calibration valve in each sensor pack. The calibration valve
can take one of four states:
It is important that all control pressures should be dry,
filtered instrument air or nitrogen.
Operate Mode
This connects each Px input to its associated
pressure sensor. The ZOC33/64PxX2 module
allows the customer to select one of two banks
for input.
Calibrate Mode
This mode connects all the pressure sensors to
the calibration input.
Purge Mode
This mode connects the Px inputs to the pressure
sensors and the calibration input. A safe purge
pressure can be applied to purge input lines.
Isolate Mode
This mode isolates the pressure sensors from the
Px and calibration lines.
Tables 3.1, 3.2 and 3.3 are state tables that describe pneu -
matic logic for each state of the valves.
Table 3.1 - ZOC33/64Px Valve
Logic
Mode Px CTL CAL CTL
Operate X 65psi
Calibrate 65psi X
Purge X X
Isolate 65psi 65psi
Table 3.2 - ZOC33/64PxX2 Valve Logic
Mode PxA CTL PxB CTL CAL CTL
Operate A X 65psi 65psi
Operate B 65psi X 65psi
Calibrate 65psi 65psi X
Purge X X X
Isolate 65psi 65psi 65psi
Table 3.3 - ZOC33/64Px Valveless
Valve Logic
Mode Px CTL CAL CTL
Operate X X
Calibrate N/A N/A
Purge N/A N/A
Isolate N/A N/A
NOTE: Valveless Modules do not have control pressure
inputs
Figure 3.5 - ZOC33/64Px Valveless Pneumatic
Inputs
Figure 3.6 - ZOC33 Channel Identification