DBL

Supported Applications

The ACI DBL Series Differential Pressure Switches are general purpose pressure switches designed for HVAC and Energy Management applications. These units sense positive, negative, or differential air pressures when used in conjunction with a sampling tube such as the DBZ-06 tubing and pitot kit, A/SPT Series, or A/VPT Series.

Operating Conditions & Performance

The series operates within an ambient temperature range of -4 to 185°F (-20 to 85°C). The maximum operating pressure is rated at 40" wc (10 kPa), with a life expectancy of 1,000,000 cycles. Measured media are limited to air and other non-combustible, non-aggressive gases.

Performance specifications include:

• Contact Rating: 250 VAC maximum, 1.5A Resistive (0.4A Inductive)
• Set Point Adjustment: Factory calibrated linear set point adjusting knob; adjustable without comparing to a field gauge, manometer, or magnehelic.
• Switching Differential: Factory default is +/- 15% of Trip / Set Point. Specific ranges vary by model (e.g., DBL-205L offers 0.04 to 0.08" wc).

Configuration Options

The series is available in four standard models covering differential pressure ranges from low static pressures up to 10 inches of water column:

• DBL-205L (Item #105934): Range 0.08 to 0.8" wc; Adjustable Switching Differential 0.04 to 0.08" wc.
• DBL-205B (Item #102423): Range 0.20 to 2.0" wc; Adjustable Switching Differential 0.08 to 0.16" wc.
• DBL-205D (Item #102424): Range 0.80 to 4.0" wc; Adjustable Switching Differential 0.40 to 0.80" wc.
• DBL-205E (Item #106255): Range 2.0 to 10.0" wc; Adjustable Switching Differential 0.60 to 1.20" wc.

Installation and Mounting Notes

The enclosure is rated NEMA 3 (IP54) weather proof plastic, containing a single stage micro switch with two pressure chambers separated by a silicone diaphragm. The unit includes a ½" conduit knockout.

• Mounting Direction: Any vertical plane; mounting in the horizontal position requires deducting 0.08 inch WC (20 Pa) from the desired setpoint for offset adjustment.
• Restrictions: Do not mount with the pressure port connection pointing downwards if mounted vertically, and never install where the setpoint knob faces downward as this causes incorrect performance.

Safety Warnings

Do not adjust the setpoint knob or screw adjustment for switching differential when high voltage power is connected. ACI does not recommend adjusting the switching differential from its factory setting, as smaller differentials might cause failures and change switch behavior.

Key Product Differences

The DBL series of plastic differential pressure switches is offered in four standard models, each covering a different portion of the series' differential-pressure range:

• DBL-205B
• DBL-205D
• DBL-205E
• DBL-205L

All four share the same plastic housing and snap-action switching; select the model whose range matches the required differential pressure.