Series-1620

Supported Applications

The Dwyer Series 1620 comprises single and dual pressure switches designed for differential, positive, or negative pressure applications. These units utilize a power diaphragm and calibrated spring mechanism to actuate a snap switch at a set point. The series is specified for service with air and non-combustible, compatible gases.

Operating Conditions & Performance

The Series 1620 operates within process temperature limits of -30 to 130°F (-34.4 to 54.4°C). Ambient temperatures should not exceed 130°F, and the location must be free from excessive vibration. The switches feature a repeatability of ±1%.

Pressure ratings are defined as Max. 50 in w.c. (12.44 kPa) continuous with a surge limit of 2 psig (13.79 kPa). Process connections consist of two 1/8" female NPT ports for high and low pressure inputs.

Operating ranges vary by model suffix, covering the following spans in w.c.:

• .15 to 1.5 (Model -1)
• .5 to 6.0 (Model -5)
• 2.0 to 11 (Model -10)
• 8.0 to 24 (Model -20)

The series supports approximate dead bands ranging from .10 in w.c. minimum on the lowest range up to .50 in w.c. minimum on the highest range, with maximum set point adjustments varying accordingly.

Configuration Options

The Series 1620 is available in two primary configurations: Model 1626 featuring a single Single-pole double-throw (SPDT) switch and Model 1627 equipped with dual SPDT switches for independent control. Both models support open or close action.

• Electrical Ratings: 15 A @ 120-480 VAC, 60 Hz; Resistive loads of 1/8 HP @ 125 VAC and 1/4 HP @ 250 VAC.
• Connections: Three screw-type electrical terminals (common, normally open, normally closed) with a 1/2 conduit connection opening sized for Ø7/8 [Ø22.23].
• Housing Options: Standard construction is available; add suffix -WP for weatherproof housing or -EXPL for explosion-proof housing (Class I, Groups C & D; Class II, Groups E, F & G; Class III).
• MIL Construction: Add suffix -MIL for MIL environmental construction.

The switches are normally calibrated for mounting in the vertical position with pressure and electrical connections pointing down. For weatherproof housing installations, pressure and electrical connections must face down when mounted. Consult the factory regarding other orientation requirements or wetted materials.

Key Product Differences

Differences between models are defined by switch count and set point adjustment capabilities:

• Model 1626 (Single Switch): Contains one SPDT electric switch. Models include 1626-1, 1626-5, 1626-10, and 1626-20.
• Model 1627 (Dual Switches): Contains two SPDT electric switches allowing for independent control. Models include 1627-1, 1627-5, 1627-10, and 1627-20.
• Dual Set Point Adjustment: Model 1627 units feature an adjustable difference between set points ranging from 0.5 in w.c. (Model -1) to 5.0 in w.c. (Model -20).

Accessories include the A-302F-A, a 303 SS static pressure tip with mounting flange for 3/16" ID tubing, and the A-489, a 4" straight static pressure tip. An optional A-331 filter vent plug is available to prevent dirt collection in dusty environments.