Differential Level Transmitter DLT2.0

Measures Level, Differential Level and Open Channel Flow
Two Non-Contacting Ultrasonic Sensors
Large White Backlit LCD Display
Three Isolated 4-20mA Outputs
Built-in 5-Key Calibration
2 Programmable Control Relays
Optional 2 Million Point Data Logger
Optional Intrinsically Safe Sensors

  • Description
  • Application Areas
  • Specifications
  • Brochure
  • User’s Guide
  • How It Works

Product Description

  • Measures Level, Differential Level and Open Channel Flow
  • Two Non-Contacting Ultrasonic Sensors
  • Large White Backlit LCD Display
  • Three Isolated 4-20mA Outputs
  • Built-in 5-Key Calibration
  • 2 Programmable Control Relays
  • Optional 2 Million Point Data Logger
  • Optional Intrinsically Safe Sensors

Reduce costs and simplify instrumentation at treatment plant headworks. The DLT 2.0 can measure both differential level plus flow through a flume. Install one Sensor on each side of a mechanical barscreen to continuously monitor, transmit and control level. Use the built-in control relays or 4-20mA outputs to automatically activate the barscreen rake at preset levels.

The DLT 2.0 is a simple solution for barscreen level control at wastewater treatment plants, pump stations and combined sewer systems. It includes two non-contacting ultrasonic sensors to measure level. With sensors positioned above a channel, up and downstream from the barscreen, the DLT 2.0 can display and transmit differential level. The downstream sensor can also be installed above a flume or weir to measure and totalize open channel flow.

Three 4-20mA outputs are configured to transmit upstream level, downstream level (or flow) and differential level. Built-in relays can be calibrated for level control, differential level control or open channel flow.

DLT 2.0 applications
include two-tank inventory where you can monitor level in two tanks with one instrument. The DLT 2.0 will alternate display of level in both tanks plus transmit 4-20mA outputs. Use the built-in relays to activate alarms or level controls. This versatile dual-sensor instrument can also be configured as a submergence alarm for Parshall flumes.

Barscreen Differential Monitor  transmit and control barscreen level with one instrument. Ultrasonic sensors mount up and downstream from a barscreen. Use the isolated 4-20mA outputs or control relays to activate the screen’s cleaning rake at preset levels or differential leveL

Two-Tank Inventory Monitor level in two tanks with one instrument. The DLT 2.0 will alternate display of level in both tanks plus transmit 4-20mA outputs. Use the built-in relays to activate alarms or level controls. Calibration is easy with the DLT’s built-in keypad and menu system.

Submerged Flow Alarm Parshall flumes can provide accurate flow measurement with the discharge submerged up to 70% (depending on flume size). Use the DLT 2.0 to measure flow through the flume and to activate an alarm when discharge level reaches critical submergence level.

Contact AKTEK for specific recommendations in your application

Barscreen level control at wastewater treatment plant headworks
pump stations
Combined sewer systems
Flow rate measuring in an open channel

General Specifications

  • Electronics Enclosure: Watertight and dust tight NEMA4X (IP 66) poly carbonate with clear, shatterproof cover
  • Accuracy: ±0.25% of Range or 2 mm (0.08") whichever is greater, Repeatability and Linearity: ±0.1%
  • Display: White, backlit matrix - displays upstream, downstream and differential level, open channel flow and totalizer, relay states, operating mode and calibration menu
  • Programming: built-in 5-key calibrator with English, French or Spanish language selection
  • Power Input: 100-240VAC 50-60Hz (see Options), 3 Watts maximum (with standard features)
  • Outputs: Three Isolated 4-20mA (upstream and downstream level (or open channel flow) and differential level, 1000 ohm load maximum.
  • Control Relays: Qty 2, rated 5 amp SPDT, programmable for level control, differential control, or flow proportional pulse
  • Electrical Surge Protection: Sensor, 4-20mA outputs and AC power input
  • Operating Temp. (electronics): -5° to 140°F (-20° to 60°C)
  • Approximate Shipping Weight: 15 lbs. (6.8 kg)

Sensor Specifications

  • Maximum Range: 15 ft (4.57 m) with standard PZ15 sensor
  • Deadband (Blanking): Programmable, Minimum 8 in (203.2 mm)
  • Beam Angle: 8°
  • Operating Frequency: 92 Khz
  • Exposed Materials: PVC
  • Operating Temperature: -40° to 150°F (-40° to 65°C)
  • Temperature Compensation: Temperature probe inside level sensor for high accuracy in changing temperatures
  • Sensor Cable: RG62AU coaxial, 25 ft (7.6 m) standard length (See Options)

Differential Level Transmitter DLT2.0 Brochure

Differential Level Transmitter DLT2.0 User Guide

Ultrasonic Level

Ultrasonic sensors are mounted at the top of a tank or in a position above the liquid being measured. The sensor continuously transmits pulses of high frequency sound (typically 42 kHz) which travel away from the sensor, hit the surface of the liquid and return to the sensor.

The instrument electronics measure the time it takes from transmitted sound to return of the echo. With reference to the speed of sound in air, the exact distance of the liquid surface from the sensor can be calculated with high accuracy (±0.25% of maximum range).

Since the speed of sound is affected by air temperature,  ultrasonic level sensors include a built-in temperature sensor. Level/distance measurements are automatically temperature compensated throughout the operating temperature range of the sensor.

The sensor should be positioned so that it has a clear "view" of the liquid surface and away from ladders, pipes or other obstructions. Greyline recommends 1 ft. from the sidewall for every 10 ft. depth (300 mm for every 3 m depth). False echoes from agitators (sweeping under the sensor), turbulence and waves can be filtered and disregarded by the instrument.