Pressure Measurement (Px) Ports; Calibration (Cal) Port; Reference (Ref) Port; Control 1 (Clt1) Port - Scanivalve DSA3217-PTP Series Operation And Service Manual

DSA3200-PTP

Pressure Measurement (Px) Ports

Each DSA-PTP module has 16 pressure measurement ports,
or Px ports. They will be labeled 1-16, or for dual range
units ± 1-8. Each of these ports are connected to a discrete
pressure transducer. If any Px ports are not being used, it
is recommended that they be plugged to prevent dust or
debris from clogging the port or contaminating the internal
calibration valve.

Calibration (CAL) Port

For each pressure range the DSA-PTP module has, there
will be a 'CAL' port. Most modules will only have one 'CAL'
port, but dual range modules will have two (labeled 'CAL'
and 'CAL B'). The 'CAL' port provides a means to apply
a known calibration pressure to a single port and have it
manifolded to all of the transducers of the related pressure
range. During normal operations, with no control pressures
applied this port in internally blocked off. Any pressure
applied to the 'CAL' port will not reach the transducers
unless the internal calibration valve has been configured
to direct the calibration pressure to the transducers. For
low pressure modules (below 5 psi) the 'CAL' port should
be routed to a known, stable static location when not being
used to apply calibration pressures. This ensures that when
a zero offset calibration (CALZ) is performed no unwanted
offsets are introduced.

Reference (REF) Port

For each pressure range the DSA-PTP module has, there
will be a 'REF' port. Most modules will only have one
'REF' port, but dual range modules will have two (labeled
'REF' and 'REF B'). On differential pressure modules, the
'REF' port is labeled 'CAL REF.' There is no 'REF' port on
absolute or individual reference pressure modules. The
'REF' port ties into a manifold that connects the back side
(or negative side) or all transducers of the same pressure
range together. During most applications, the 'REF' port
of low pressure modules (below 5 psi) should be routed
to a known, stable static location. This ensures that when
a zero offset calibration (CALZ) is performed no unwanted
offsets are introduced. During a calibration, positive pres-
sures will be applied through the 'REF' port to perform the
negative portion of the calibration.

Control 1 (CLT1) Port

Control 1 (CTL1) is the 'isolation' control. Applying 90-120
psi to the CTL1 port closes a normally open (flow) valve and
configures the internal calibration valves into isolate mode,
meaning that pressures applied to the pressure measure-
ment ports (Px 1-16) will not reach the transducers. CTL1
controls both internal calibration valves simultaneously,
they cannot be operated separately. Ensure that any con-
trol air applied to CTL1 is clean, dry instrument grade air or
nitrogen.

Control 2 (CTL2) Port

Control 2 (CTL2) is the 'calibration' control. Applying
90-120 psi to the CTL2 port opens a normally closed (no
flow) valve and configured the internal calibration valve
into calibration mode, meaning that pressures applied to
the 'CAL' port(s) will reach the transducers. CTL2 controls
both internal calibration valves simultaneously, they cannot
be operated separately. Ensure that any control air applied
to CTL2 is clean, dry instrument grade air or nitrogen.

Control Supply (CTL SUPPLY or CTL)

The Control Supply port (CTL SUPPLY on DSA3217-PTP, CTL
on DSA3218-PTP) is only required when the quick zero
jumper is being used. In this case, 90-120 psi is applied to
the CTL Supply port and through the quick zero jumper is
directed to the CTL1 and CTL2 ports to put the DSA-PTP
module into zero offset calibration (CALZ) mode. This
allows the user to remotely perform zero offset calibration
(CALZ) as long as 90-120 psi is supplied to the CTL Supply
port. For more information on the quick zero jumper, refer-
ence "Quick Zero Jumper" on page 14.

Return (RTN) Port

Like the Control Supply port, the Return (RTN) port is only
required when using the quick zero jumper. 90-120 psi
control air that is supplied through the Control Supply port
is switched internally within the module, and when com-
manded returned out of the Return port to be used to put
the module into zero offset calibration (CALZ) mode. For
this to function correctly, the quick zero jumper must be
installed between the Return (RTN), Control 1 (CTL1) and
Control 2 (CLT2) ports. For more detailed information on
the quick zero jumper, reference "Quick Zero Jumper" on
page 14
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Section 4: Hardware