Series-616KD-LR

Supported Applications

The Dwyer Series 616KD-LR is a low-range differential pressure transmitter designed to sense the pressure of air and non-combustible, compatible gases. The series provides factory-calibrated models for applications requiring precise monitoring in environments such as air handlers, where space constraints and installation simplicity are priorities.

Operating Conditions & Performance

The Series 616KD-LR operates within an ambient temperature range of 0 to 140°F (-17.8 to 60°C). It is rated for a maximum operating pressure of 1 psi with a burst pressure rating of 10 psi. The device features a response time defined by a 2.5 Hz sample rate and maintains stability within ±1% / year FSO.

Accuracy varies by measurement range as specified in the series documentation:

• ±0.25% FS for ranges of ±0.4" (100 Pa) and ±0.5" (125 Pa)
• ±0.5% FS for a range of ±0.25" (60 Pa)
• ±1% FS for a range of ±0.1" (25 Pa)

The enclosure carries an NEMA 1 (IP20) rating, and the unit weighs 1.8 oz (51 g).

Voltage & Load Requirements

• Power Supply: 10 to 35 VDC for 2-wire operation; 17 to 36 VDC or isolated 21.6 to 33 VAC for 3-wire operation.
• Load Resistance: Current output supports a maximum of 0 to 1250Ω; voltage output requires a minimum load resistance of 1kΩ.

Configuration Options

The series offers configurable options for process connections, electrical outputs, and calibration features. Models are available with specific accuracy classes denoted by suffix codes (e.g., -A for 0.25% FS, -B for 1.0% FS, -D for 0.5% FS).

Process Connections

• Barbed: Dual size to fit 1/8" and 3/16" (3 mm and 5 mm) ID rubber or vinyl tubing.
• NPT: Available as a 1/4" NPT connection block; some configurations feature a front push button with the process port.

Output Signals & Electrical Connections

• 2-Wire Output: 4 to 20 mA (simultaneous voltage outputs available in specific combinations).
• 3-Wire Outputs: 0 to 5 VDC or 0 to 10 VDC.
• Electrical Interface: Screw-type terminal block; European style removable terminals support wire gauges from 16 to 26 AWG.

Calibration & Options

The transmitter utilizes digital push buttons for zero and span adjustments, eliminating the need for separate reference pressure sources or turn pots during calibration. A 5-second delay occurs after button release before the change takes effect to prevent stress-related offsets on lower ranges.

• Mounting: Integral DIN rail mounting kit (35 mm) allows side or back mounting; vertical orientation with pressure connections pointing down is required for operation.
• Certifications & Documentation: CE approved. Optional plenum-rated units meet UL Standard 2043. Available options include aluminum tags, terminal covers, factory calibration certificates, and NIST traceable calibration certificates.

Key Product Differences

The Series 616KD-LR distinguishes itself through specific range codes that define the measurement span in both inches of water column (in w.c.) and Pascals (Pa). The series supports unidirectional ranges (e.g., 0 to 0.4 in w.c.) and bidirectional differential ranges (e.g., 0 to ±0.4 in w.c.).

Model construction follows the pattern SERIES-ACCURACY-RANGE-PROCESS CONNECTION-OUTPUT-OPTIONS. For example, a model code ending in "34" indicates a range of 0 to 0.4 in w.c., while "45" denotes 0 to ±0.5 in w.c. Accuracy codes (-A, -B, -D) determine the precision class available for specific ranges; note that certain low-range options (e.g., 25 Pa or 60 Pa) may be restricted to B and C accuracy classes depending on configuration.

Wetted materials are not explicitly listed in standard documentation; users must consult the factory for compatibility with gases other than air. The unit is not field serviceable, and repair requires returning the device to Dwyer Instruments after obtaining a Return Goods Authorization number.