Series-DM

Supported Applications

The Dwyer Series DM DigiMag® Differential Pressure Transmitter is designed to sense the pressure of air and non-combustible, compatible gases. The transmitter provides a standard 4-20 mA output signal for integration into control systems monitoring differential pressure conditions.

Operating Conditions & Performance

The Series DM operates within an ambient temperature range of -4 to 158°F (-20 to 70°C). Accuracy is specified as ±1% FSO for most ranges, with specific exceptions: the 0.25 in w.c. range offers ±2% FSO accuracy, and ranges at or below ±0.1 in w.c. offer ±4% FSO accuracy. Stability is rated at < ±1%/year FSO.

Pressure limits vary by measurement range:

• Ranges > 1 in w.c.: 6 psi max operation, 6 psi burst
• Ranges ≤ 1 in w.c.: 3.6 psi max operation, 6 psi burst

The unit features a thermal effect of 0.036% FS/°C (0.02% FS/°F). Response time is configurable via buttons for Fast (0 seconds) or dampened (4 seconds) response.

Configuration Options

The series offers a wide range of factory-calibrated models covering differential pressure ranges from 0.1 in w.c. to ±1250 Pa, including specific options for mm w.c. and negative-to-positive spans such as -0.05-0.20 in w.c.

Key configurable features include:

• Housing & Mounting: Polycarbonate molded housing with integral pressure connections, designed to mount in the same 5" OD (127 mm) cutout as a standard Magnehelic® gage. The unit is not sensitive to mounting orientation.
• Process Connections: Male ports on the side accommodate flexible tubing sizes of 1/8", 3/16", 1/4", 5 mm, and 6 mm ID.
• Electrical Interface: Screw-type terminals for a 2-wire system powered by 10-35 VDC. Maximum loop resistance is 0 to 1250 Ω max., with current consumption up to 21 mA max.
• Calibration & Display: Digital push-button zero and span adjustments replace turn-potentiometers. A single push-button allows field selection of 4 to 6 engineering units depending on the range.

The enclosure is rated NEMA 4X (IP66). Wetted materials should be confirmed by consulting the factory.

Key Product Differences

Different models within the Series DM are distinguished primarily by their calibrated pressure ranges. Model numbers follow a specific code structure where suffixes indicate options:

• -FC: Factory calibration certificate
• -LG: Light grey overlay
• -NIST: NIST traceable calibration certificate
• -SS: 304 brushed SS bezel

The series includes models for positive-only ranges (e.g., DM-001 at 0.1 in w.c.) and bidirectional ranges (e.g., DM-202 at ±0.25 in w.c.). The unit carries CE approval.