Introduction:

The Meriam Model M330 is an accurate, fully compensated, self-contained, digital pressure measurement instrument designed to be tightly integrated into your systems. Ideal for integrators and designers familiar with C/C++, Visual Basic or LabVIEW® programming, these instruments accommodate digital communication using UART or I2C hardware layers (both standard). A Development Kit is available to assist with the integration effort.

The M330 EPI is designed for OEMs who require accurate, temperature compensated pressure measurements but do not want the expense of designing and maintaining the calibration infrastructure necessary for this precision. M330 brings Meriam’s 25 years of experience in these areas directly to your system. In addition, the M330 communicates digitally for best possible accuracy, uses no internal hoses, eliminating potential leak paths, and can be field re-calibrated using the standard command set provided.

Table A:
Available Pressure Ranges and Wetted Parts

Examples:   M330-DN0415 = M330, Differential Non-isolated, 0 - 415” H2O full scale measurement
                  M330-GI1000 = M330, Gauge Isolated, 0 - 1000 PSIG full scale measurement
                  M330-CI0100 = M330, Compound Isolated, -14.7 to +100 PSIG full scale measurement

Performance:

Single of Dual Pressure Sensors

M330 is for a single pressure sensor of any type and range listed in the table above. Model M332 includes dual pressure sensors using the standard enclosure and pressure manifold using any combination of GI, CI or AI pressure sensors. A customized M332, without the standard enclosure, can accommodate any combination of two pressure sensors including differential (DN or DI) sensors. This option can reduce the total purchase price, installation cost and the mechanical foot print within a system. The same “Get Measure” command issued to the M332 returns both pressure measurements.

Dual sensor example: M332-AI0017-GI0030 = M332 dual sensor unit, P1 location is a AI0017 Absolute sensor and P2 location is a GI0030 Gauge sensor

Measurement Accuracy and Temperature Performance

±0.025% of F.S. (unless otherwise noted) including all affects of linearity, repeatability, hysteresis and temperature from -4º to +122º F (-20º to +50º C).

Operating Temperature: -4º to +122º F (-20º to +50º C)
Storage Temperature: -40º to +185º F (-40º to +85º C)

Temperature Measurement
M330 measures sensor temperatures from -4º to +122º F (-20º to +50º C).
Accuracy is ±3.6º F (±2º C)

Update Rate
M330 Single Pressure Sensor Models: 14 fully compensated samples per second
M332 Dual Pressure Sensor Models: 7 fully compensated sample per second
Contact the factory for faster update rates

Pressure Connections
1/8” NPT(F) for all pressure types and ranges. DI types available with optional flushing ports and plugs.

Overpressure Limits by Sensor Type
DN: 2x range when pressurized on P1 (High) side only, 150 PSI when applied simultaneously to P1 (High) and P2 (Low) sides.
DI: 1000 PSI common mode pressure, P1 (High) side only 3x range, P2 (Low) side only 3x range or 150 PSI, whichever is less.
GI, CI & AI: 2x Full Scale

Power and Power Connections
Power Requirements: 4.2 to 9 VDC excitation Consumption: less than 20 milliWatts
Standard Connector: .1 pitch, 20 pin header (2 rows of 10 pins) Custom (without enclosure): Capton cable

Pressure Units
Select from 32 standard units or set up two user-defined units

Standard Enclosure
IP40, aluminum case, 316LSS pressure manifold Dimensions: 3.81” L x 2.125” W x 1.25” H Weight: 10 oz for DN, GI, CI and AI pressure types, 13 oz for DI type

Customization
Options may be available for pressure connections, pressure manifold styles & materials, communication connections and enclosure style. A few of the possible variations are shown below. Consult Meriam to discuss your customization needs.

Programming & Integration
The M330 uses Meriam Serial Protocol (MSP) over a UART or I2C hardware layer for communication with the host system. Customers will need expertise with suitable development software such as C/C++, Visual Basic or LabVIEW® to implement the MSP commands.

M330 Development Kit
The M330 Development Kit (pn Z9A450) allows the M330 to connect directly to a host PC (USB cable included) for software development. The MSP Implementation Guide documents the protocol command strings. The Kit includes the M330 Development Interface, USB cable (type B by type A), MSP Implementation Guide and samples of source code implementing various commands.