ModelMPS4164

Miniature Analog Pressure ScannerFeatures• New valve design provides "isolate-purge"• On board sensor excitation• 40kHz data output• Double-isolated, ultra-stable pressuresensors• Direct legacy compatability with ZOC seriesscanners• Removable input headers• Upgradable to Ethernet MPS4264 standard

MPS4164 Analog
Pressure Scanner

General Description
The MPS4164 analog miniature pressure scanner
is an extremely compact 64 channel pressure
scanner.  It has been designed from the groundup with size, accuracy and functionality inmind.  Each MPS4164 module incorporates 64
individual silicon pressure sensors, calibration
valving, a high-speed multiplexer (45kHz) and an
instrumentation amplifier.  Simply, it accepts up
to 64 individual pneumatic pressure inputs andconverts them to high level electronic signals.  Itboasts a small footprint, a rugged isolate-purge
calibration valve, extremely stable and repeatablepressure sensors and a wealth of other innovativefeatures.
The MPS4164 is designed around a core sensor
pack that uses a custom packaged, ultra-stablesensor. Scanivalve engineers evaluated knowncauses of non-repeatability in piezoresistive
pressure transducers.  Designing a double
isolation method of bonding the sensors tothe base substrates (patented) minimizes themechanical influences of assembly and thermal
expansion. This process dramatically improves thestability and the resulting accuracy of the sensors.
A brand new valve has been designed that fully
isolates the sensors from purge pressure andprovides long term, maintenance free operation.  
Not only is the valve design an improvement overlegacy products, but two different valve actuation
options are available.  The "standard" (CPx)actuation uses opposing 65psi control pressures

to shift the valve into whichever state is desired.  
The new "Normal Px" (NPx) option uses a spring
to default the valve into measurement mode and120psi to shift it into calibrate mode.    

Applications
The MPS4164 electronic pressure scanning module is specifically designed for use in wind tunnel and flight tests where operational conditions
are very space constrained and pressures do not
exceed 50 psi. It is ideal for use inside small supersonic wind tunnel models.
The very low pressure ranges offered and smallsize also make it an ideal fit for wind engineering
applications where the measurement pressures arevery low.  In high channel count systems, the lower
cost-per channel makes it an affordable solution.
It may be mounted in any position so the pressure
sensors may be close coupled to the pressuresources to be measured. Removable headers allow
for easy installation and removal without breaking
the pneumatic lines.
The MPS4164 module is designed to be used inconjunction with Scanivalve model ERAD4000 Remote A/D or model DSM4000 Digital Service Module. Each MPS4164 pressure scanner incorporates
an embedded RTD to monitor the temperature ofthe pressure sensors. The ERAD4000 communicates via Ethernet. The DSM4000 communicates
via Ethernet, RS-232, or ARINC 429.
ISO 9001:2015 CERTIFIED

Removable input
headers(available with0.031" and0.042" tubes)

Multiple mounting options(side and bottom)

Legacy Compatibility
The MPS4164 was designed specifically to replace
the legacy ZOC series of pressure scanners. ThisMPS can directly replace a ZOC33 64-channel
analog scanner.  It can be a drop-in replacement
for the ZOC33 or can be used to expand anexisting ZOC33 system.  
The electrical interface of the MPS4164 is exactly
the same as a ZOC scanner.  The electricalconnector is the same meaning it operates using
existing cabling and hardware infastructure.  
Firmware in the DSM4000 and the ERAD4000 canbe easily field-updated to support the MPS4164*.  
An integrated TEDs ID chip in the MPS4164
supports automatic system configuration at system
power-up.  
The pneumatic interface and valve logic of theMPS4164 is also the same as a ZOC scanner.  Inthe "CPx" configuration, the MPS4164 operates
65psi control pressures with the same control logic
as a ZOC33.  This allows single logic operation in
mixed ZOC/MPS4164 system.
While directly legacy compatible with the ZOC
scanners, the MPS4164 offers many featureupgrades.  Overall sensor performance isimproved, the operating temperature is extended,
the scanner is physically smaller and the MPS
valve includes full "isolate-purge" functionality.
*DSM4000 firmware V2.16 and ERAD4000 firmware V2.19 and later fully
support MPS4164

AnalogInterface
Connection

Improved sensors, Improved
Accuracy
The primary focus of the MPS4164 was to improvethe unit's overall accuracy across the entire
temperature range.  Scanivalve worked directlywith a leading sensor designer to create a custom
sensor package specifically for the MPS seriesof scanners.  This design uses two layers of RTV
to isolate the pressure sensor from mechanicalinfluences like those caused by thermal expansion
or assembly.  Piezoresistive sensors also change
greatly in span and zero over temperature so
we placed eight individual RTDs in very close
proximity to the sensors.  Combined with the design
placing the sensors in an aluminum housing in thecenter of the module to prevent rapid temperaturechanges, these RTDs allow us to accurately correct
for any change in the sensor's behavior due totemperature.   

MPS4164
SensorPackExploded
view of thevalve

Removablepressure input
headers are
standard

Pneumatic Calibration Valve
The valve design is a sliding-type valve.  Analuminum shuttle, populated with self-lubricating
O-rings cycles back and forth between twopositions to achieve each of the pneumatic states.  
The "bearing plate" between the sliding O-rings andthe aluminum stationary portion of the valve is aproprietary compound that is extremely low friction.  
The O-rings are supported completely to preventany deformation during a state change.  The valve
shuttle is supported on ball bearings to provide
minimal friction and maximum support.  This design
allows for low actuation force and minimal “stiction”- meaning the actuation force does not noticeably
increase after long periods of dormancy.  Samplesof the valve design were tested to over 1,000,000
cycles without maintenance.

Existing pressure scanners require outside pneumaticpressure as a force to switch the valve logic.  In
most applications, this "control pressure" must becontinuously supplied to the scanner to maintain thedesired valve state.  The MPS4164 offers a unique
option with a valve that defaults to the "measurement"mode, allowing sample pressures to be read without
any outside pneumatic control pressure.  This option,
called "Normal Px," is another way the MPS4164
simplifies system architecture.
An optical valve position sensor has been integrated
allowing the valve state to be queried with a simple
software command.

Example Wind Tunnel System Architecture

Shown using ERAD4000 mounted in the test article. Alternatesystem configuration uses DSM4000 installed under the test
section or in the control room.

Specifications (for MPS4164 version)

Maximum
Reference Pressure:

Inputs (Px):0.042" [1.067mm] OD (standard)
0.031" [.787mm] OD (optional)

Maximum
Environment Pressure:100 psia (690kPa absolute)

Inputs(Cal, Ref, CTL, Prg):        0.063" [1.600mm] OD

Minimum
Environment Pressure: 0.5 psia (3.45kPa absolute)             Full Scale 					Ranges:4 inH2O, 8 inH2O, 1psid, 5psid,15psid, 50psid[995.4Pa, 1990.7Pa, 6.89kPa,34.5kPa, 103.4kPa, 344.7kPa]
Accuracy*:

4 inH2O:
8 inH2O:
1psid:
5psid:
15psid:50psid

0.20%FS
0.15%FS
0.08%FS
0.08%FS
0.08%FS
0.08%FS

Shock & Vibration:

MIL-STD-810G, Category 24

Scan Rate:

40kHz (standalone)

Power
Requirements:

P34
P33

65psi (CPx)120psi (NPx)Electrical Connector:		 15 pin MDM 15SL2P				
Weight:6.59oz [186.9g]

OperatingTemperature:

0° to 70°C

Storage Temperature: 0° to 80°C
* Non-standard pressure ranges may result in a reduction of accuracy. Please contact
Scanivalve for more information.

Dimensions (for MPS4164 version) Inches [mm]
CALIBRATION CONTROLPRESSURE INPUT(CALCTL)+15Vdc @ 120mA-15Vdc @ 30mA

Control Pressure
Requirements:

Overpressure						Capability:
4 inH2O:        25x8 inH2O:        15x1psid:       15x5psid:       10x15psid:       5x50psid:              2xMedia		Compatibility:
Gases compatible with silicon,silicone, aluminum, and Buna-N

50 psig (345kPa)

ISOLATE-PURGE(PRG)
CHANNEL 33~64
P48
P47

P50
P49

MEASUREMENT CONTROLPRESSURE INPUT(Px CTL) FOR CPx
SPRING RETURN FOR NPx

P64
P63

22.23.875
MTG HOLEANALOG CABLE
CONNECTION(MATE: 15 PIN MDM 15SL2P)REFERENCEPRESSURE INPUT(REF)CALIBRATIONPRESSURE INPUT
(CAL)

P2

P16P18P32P1P15P17P31

ISOLATE-PURGE(PRG)
CHANNEL 1~32
99.31
3.910
MTG HOLE

3.18.125
MOUNTING
HOLE

6.86
.270

.659
31.98
1.259

36.12
1.422

29.08
1.145

1.27
.050

89.28
3.515
105.41
4.150

Scanivalve Headquarters
1722 N. Madson Street
Liberty Lake, WA 99019
Tel: 509-891-9970
800-935-5151
Fax: 509-891-9481
e-mail: scanco@scanivalve.com
Printed in USA©
2019, Scanivalve Corp.

www.scanivalve.com
2006