Scanivalve ZOC 33/64Px, Instruction And Service Manual

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ZOC33
Section 3: Installation & Operation
Pneumatic Inputs
Pneumatic inputs consist of: Px Inputs(8 or 16), Control
Pressure Inputs ( PxA Ctl, Cal Ctl), a Calibration Input, and
a Reference Input. The duplex version also has a duplex
control pressure input (PxB). Valveless units do not have
Control Pressure and Calibration Inputs
All Px inputs are .040 inch(1.067mm) bulged tubulations.
These tubulations are designed to accept any .042 inch
tubing manufactured by Scanivalve Corp. Each sensor pack
valve block contains eight (8) or, in the duplex version,
sixteen(16) Px inputs. ZOC33 modules are capable of mea -
suring pressures up to 50 psid.
Control pressure inputs consist of: PxA CTL and CAL CTL.
The duplex module has a third control pressure input, PxB
CTL. These inputs are used to switch the valve logic to each
of the four (4) states: Operate, Calibrate, Purge, and Isolate.
The control pressures must be 65 psi. Figure 3.3 shows the
64Px valve logic. Figure 3.4 shows the 64PxX2 Valve Logic.
Calibration/Reference Inputs consist of a Calibration input
and a Reference input. The Calibration input is an .042 inch
O.D. tubulation. It is normally connected to a source of
calibration pressures. Internally, this input is manifolded
to all of the sensors through the calibration valving. The
Reference input is an .063 inch (1.6mm)O.D. tubulation. It
provides a point of reference for the transducers. All of the
sensors in each block of eight share a single reference.
Manifold blocks are provided with the module to facilitate
plumbing. This also permits easy removal of a sensor pack
in the event that field repairs are required.
Figure 3.3 - ZOC33/64Px Pneumatic Inputs
Figure 3.4 - ZOC33/64PxX2 Pneumatic Inputs