Series-MSX-Pro

Supported Applications

The Dwyer Series MSX Pro Magnesense® Differential Pressure Transmitter is designed for critical building performance applications. It monitors uni- or bidirectional differential pressure and can calculate linear velocity or flow via square root extraction. The transmitter delivers outputs in specified units (in w.c., mm w.c., Pa) suitable for HVAC control systems.

Service media includes air and non-combustible, compatible gases. Wetted materials should be confirmed by consulting the factory.

Operating Conditions & Performance

The Series MSX Pro operates within an ambient temperature range of -4 to 158°F (-20 to 70°C). Accuracy is specified as ±0.5% FSO for all ranges, except the unidirectional .5 in w.c. range which is rated at ±1% FSO. Long-term stability is documented as ±1% FSO/year.

Pressure limits vary by selected range:

• Ranges 0 and 1: 3.6 psi max operation, 6 psi burst
• Ranges 2, 3, and 4: 6 psi max operation, 6 psi burst

Response time is instantaneous by default or selectable to 3 seconds via DIP switch configuration.

Configuration Options

The series supports a total of 32 pressure ranges across five range groups (0 through 4), configurable for unidirectional (0-based) or bidirectional (± maximum span) operation. Units are selectable as in w.c., mm w.c., Pa, kPa, FPM, m/s, CFM, or CMH.

Output signals and power configurations include:

• 2-wire output: 4-20 mA with 10-36 VDC supply (max loop resistance 0-1250 Ω)
• 3-wire output: Selectable 0-10 V or 0-5 V with 17-36 VDC or isolated 21.6-33 VAC supply
• Simultaneous outputs: Current and voltage available when using a DC power supply (not designed for AC operation)

The enclosure is rated NEMA 4X (IP66) with UL 2043 (Plenum) and UL94 V-0 compliance. Electrical entry uses a 1/2" NPS thread with an included cable gland, connecting to a 4-position removable terminal block for 16 to 26 AWG wire.

Process connections accept flexible tubing in sizes: 1/8", 3/16", 1/4", 5 mm, and 6 mm ID. Mounting options include wall mount brackets, duct mount brackets (universal model required), and DIN rail mounts. An optional 4-digit LCD display is available for local viewing.

Key Product Differences

The Series MSX Pro includes communicating models that support BACnet MS/TP or Modbus® RTU protocols over TIA/EIA-485 interfaces, distinct from the standard analog output variants. Communication parameters such as baud rate (9600 to 115200), parity, and stop bits are configurable via DIP switches.

Models differ by mounting style (Universal vs. Wall/DIN) and directionality (Unidirectional vs. Bidirectional). The optional LCD display is a separate accessory that plugs into the circuit board pins; it must be removed prior to wiring if installed. Factory calibration certificates are available as options, including NIST traceable versions.