Series-626-628

Supported Applications

The Dwyer Series 626 and 628 are industrial pressure transmitters designed to monitor compatible gases and liquids. The product overview identifies specific use cases in precision irrigation and outdoor power equipment applications. These piezo-resistive sensors convert single positive pressure into standard electrical signals for process monitoring.

Operating Conditions & Performance

The series offers two accuracy classes: Series 626 provides 0.25% FS (Full Scale) and 0.20% RSS, while Series 628 delivers 1.0% FS and 0.5% RSS. For absolute pressure ranges in the Series 626, accuracy is specified as 0.5% FS or 0.35% RSS. These figures include linearity, hysteresis, and repeatability.

Performance specifications are defined across a compensated temperature range of 0 °F to 175 °F (-18 °C to 79 °C), with process temperatures supported up to 200 °F (93 °C). The thermal effect is ±0.02% FS/°F for Series 626 and ±0.04% FS/°F for Series 628, including zero and span. Response time is rated at 300 ms.

Pressure limits vary by range; for example, the 0 to 5 psi range lists a maximum pressure of 10 psi with an overpressure limit of 50 psi. The series supports measurement ranges from 0 psia to 300 psia (absolute) and 0 psi to 8000 psi (gauge), as well as metric options including 0 bar to 40 bar.

Configuration Options

The series is configurable across housings, process connections, electrical terminations, and output signals. The enclosure rating is NEMA 4X (IP66).

• Housing Options: Available in a stainless steel general purpose housing (-GH) or a cast aluminum conduit box housing (-CB). Wetted materials are Type 316L SS, with C-276 available as an option.
• Process Connections: Includes 1/8", 1/4", and 1/2" male NPT; 1/4" female NPT; 1/4" male or female BSPT; 1/8" or 1/4" male BSPT ISO 1179; and 1/4" female SAE valve depressor.
• Electrical Connections: Options include wire end, Hirschman DIN EN 175301-803-C, Packard, Deutsch, M12 connectors (UL listed or non-UL listed), cable glands with prewired cables (3', 9'), and 1/2" female NPT conduit.
• Output Signals: Supports 4 mA to 20 mA; voltage outputs of 0 Vdc to 5 Vdc, 1 Vdc to 5 Vdc, 0.5 Vdc to 4.5 Vdc (ratiometric), 0 Vdc to 10 Vdc, and 2 Vdc to 10 Vdc. The -CB option supports field-selectable voltage outputs.
• Approvals: Standard CE compliance is included; optional certifications include NSF/ANSI 61/372, ANSI/UL 218, ANSI/UL 508, and NEPA 20.

Key Product Differences

The primary distinction between the two series is accuracy. Series 626 models are designated for higher precision (0.25% FS), while Series 628 models offer standard industrial accuracy (1.0% FS). The conduit box housing (-CB) variant features a removable terminal block and an internal zero adjustment button, whereas the general purpose housing (-GH) is compact with various pre-wired or connector options.

Specific ranges are restricted by housing type; absolute pressure ranges (e.g., 0 psia to 15 psia through 300 psia) are available only on -GH housing models. The series also offers optional accessories including a field-upgradeable LCD display (-A-62X-LCD), NIST traceable calibration certificates, and special cleaning for oxygen use.