Model-ULSS

Supported Applications

The Dwyer Series ULS (Models ULSS, ULSM, and ULSL) provides non-contact, continuous ultrasonic level measurement for fluids in small to medium-sized tanks. Designed as a replacement for float, conductance, and pressure sensors that fail due to contact with dirty, sticking, or scaling media, the series is applied in skid, machine, tool, and process applications.

The general purpose sensors offer single and multi-function capabilities including measurement, switching, and control. The Series ULS is not designed for operation when immersed; it must be mounted so the enclosure and transducer do not contact application media under normal conditions. Additionally, these units are not intended for use within classified hazardous environments.

Operating Conditions & Performance

The series covers three distinct measurement ranges: ULSS-10 up to 49.2" (1.25m), ULSM-10 up to 9.8' (3.0m), and ULSL-10 up to 18.0' (5.5m). Accuracy varies by model: ULSS provides 0.125" (3mm) accuracy, while ULSM and ULSL provide +/- 0.2% of range. Resolution is specified as 0.019" (0.5mm) for ULSS, 0.039" (1mm) for ULSM, and 0.079" (2mm) for ULSL.

Operating limits include a process temperature of 20° to 140°F (-7° to 60°C) with automatic temperature compensation, and an ambient temperature range of -31° to 140°F (-35° to 60°C). The maximum working pressure (MWP) is rated at 30 PSI. Each model features a specific dead band: ULSS has a 2" (5 cm) blind zone, ULSM has a 4" (10 cm) blind zone, and ULSL has an 8" (20 cm) blind zone.

Configuration Options

The series is configurable across mounting interfaces, output signals, and relay logic to suit specific installation needs. Key capabilities include:

• Housing & Materials: Enclosures are Type 6P encapsulated (IP68) with corrosion resistance and submersible ratings. The housing material is Polycarbonate with a TPE strain relief gland. Wetted materials consist of a Polyvinylidene Fluoride (PVDF) transducer and an FKM mount gasket.
• Process Connections: ULSS and ULSM models feature 1" NPT (1" G) threads, while the ULSL model utilizes a 2" NPT (2" G) connection. Optional reducer bushings are available for various pipe sizes including sch. 40 and sch. 80 PVC fittings.
• Electrical Output: All models provide a 4-20 mA, two-wire signal powered by 12-28 VDC with a maximum loop resistance of 400 Ohms. The output is invertible (4-20 mA or 20-4 mA) and supports fail-safe modes including 4 mA, 20 mA, 21 mA, 22 mA, or hold last.
• Relay Control: Units include four SPST relays rated at 60 VA, 1A maximum. Relay hysteresis is selectable (no hysteresis, 1/4", 1/2", 1", 1/2 cm, 1 cm, 2 cm, or 5 cm). Fail-safe behavior for power loss holds the last contact state; on power up, contacts can be set to open, close, or hold last.
• Configuration: Programming is performed via free PC software using a USB adaptor (Part# ULS-ACC-USB) connected through the 9-conductor shielded polyurethane jacket cable. Memory is non-volatile.

Key Product Differences

The Series ULS differentiates models primarily by measurement range and physical dimensions:

• ULSS-10 (Short Range): Designed for ranges up to 49.2" (1.25m). Features a body diameter of 3-1/4" [82.55] with an overall height of 2" [50.85]. Includes a 1" NPT process connection and a beam width of 2" (5cm).
• ULSM-10 (Medium Range): Designed for ranges up to 9.8' (3 m). Features a body diameter of 3-5/64" [78.18] with an overall height of 2-45/64" [68.66]. Includes a 1" NPT process connection and a beam width of 2" (5cm).
• ULSL-10 (Long Range): Designed for ranges up to 18' (5.5 m). Features the same body diameter as ULSM but utilizes a larger 3" (7.6 cm) beam width and requires a 2" NPT process connection.