DQL Measurement Light Curtain (Measuring Grating)

High-precision measuring light curtain for industrial automation. Spacings 1.25 / 2.5 / 5 / 10 / 20 / 40 / 80 mm; typical range 0.3–3 m (1.25 mm: 0.2–1 m); ambient light immunity ≥10,000 Lux; response time ≤ 15 ms; enclosure IP65. Outputs: RS485 / 4–20 mA / 0–10 V for analog/serial measurement.

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DQL Measurement Light Curtain main image
DQL measuring scenarios
Measuring / sizing scenarios
DQL dimensions and wiring
Dimensions & wiring
DQL applications
Typical applications
Product Highlights
  • High precision: minimum spacing 1.25 / 2.5 mm options for fine measurement.
  • Fast & reliable: ≤15 ms typical response; robust self-diagnostics to ensure valid data.
  • Industrial outputs: RS485 (Modbus RTU), 4–20 mA / 0–10 V analog—easy to integrate with PLC/SCADA.
  • Strong immunity: resists EMI, welding arc, strobe; ambient light immunity ≥10,000 Lux.
  • Durable body: Aluminum profile, IP65; shock-resistant SMT design.
  • Flexible installation: Circular aviation connector, dedicated cables; multiple mounting kits.

Measurement distance for 1.25 mm versions is typically 0.2–1 m; other spacings 0.3–3 m (0.3–6 m optional).

Spacing & Use Guide
Spacing (K)Typical Use
1.25 / 2.5 mmFine height / edge / profile measurement; precision sizing & counting
5 / 10 mmGeneral dimensioning, presence/height measurement
20 / 40 / 80 mmLarge object sizing, passage counting, area detection

Protective/measurement height H = (n − 1) × K. Overall length L ≈ H + addon (see spec tables).

Technical Parameters (DQL Series)

CategoryItemTypical Value / OptionNotes
OpticalOperating principleThrough-beam infrared LED, modulatedEmitter/receiver pair; synchronous scanning
Spacing (K)1.25 / 2.5 / 5 / 10 / 20 / 40 / 80 mm1.25 & 2.5 mm for fine measurement
Measurement height (H)H = (n−1) × Kn = number of beams
Response time≤ 15 msVaries with beams
Ambient light immunity≥ 10,000 LuxIncidence ≥ 5°
Range0.3–3 m (typ.); 1.25 mm: 0.2–1 m0.3–6 m optional (except 1.25 mm)
Electrical / I/OSupplyDC 12/24 V; AC 110–220 V (with controller)Reverse/over-voltage protection
OutputsRS485 (Modbus RTU) / 4–20 mA / 0–10 VReal-time measuring data
IndicatorsPower / Beam OK / BlockClear status display
ConnectorCircular aviation connectorDedicated cables
Short/over-current protectionYesAuto recovery
SynchronizationOpticalFewer cables, strong immunity
ProtocolModbus RTU 4800–38400 bps8N1, 16-bit CRC
Mechanical / EnvironmentBody sectionApprox. 36 × 36 mmAluminum, ABS reinforced nylon endcaps
Overall lengthL ≈ H + addonAddon depends on K
Ingress protectionIP65Dust-tight, water-jet resistant
Operating temp.−10 ~ +40 °CStorage −25 ~ +55 °C
HumidityOperating 35–85 %RHStorage 35–95 %RH

DQL Series Detailed Specifications

Tables list typical beam counts (n) for each spacing (K) with measurement height H and overall length L. Model format: DQLnn/K-H. Example: DQL40/2.5-97.5. Output mode is selected by wiring (RS485 / 4–20 mA / 0–10 V).

K (mm)Beams nMeasurement Height H (mm)Overall Length L (mm)Model ExampleRangeOutputs
1.256478.8132.8DQL64/1.25-78.80.2–1 mRS485 / 4–20 mA / 0–10 V
1.2596118.8172.8DQL96/1.25-118.80.2–1 mRS485 / 4–20 mA / 0–10 V
1.25128158.8212.8DQL128/1.25-158.80.2–1 mRS485 / 4–20 mA / 0–10 V
1.25160198.8252.8DQL160/1.25-198.80.2–1 mRS485 / 4–20 mA / 0–10 V
1.25192238.8292.8DQL192/1.25-238.80.2–1 mRS485 / 4–20 mA / 0–10 V
1.25224278.8332.8DQL224/1.25-278.80.2–1 mRS485 / 4–20 mA / 0–10 V
1.25256318.8372.8DQL256/1.25-318.80.2–1 mRS485 / 4–20 mA / 0–10 V
1.25288358.8412.8DQL288/1.25-358.80.2–1 mRS485 / 4–20 mA / 0–10 V

Model format DQLnn/K-H. For long-range (0.3–6 m) builds (except 1.25 mm), specify on order.

Typical Applications

  • Sizing / profiling / height: online size inspection, profile gauging, accuracy correction.
  • Counting / sorting: logistics, packaging, lanes; piece counting and classification.
  • Wood / board / tube: length/diameter, edge detection, cut control.
  • General automation: connect RS485 / analog to PLC or DAQ for measurement and monitoring.

For safety stop functions use DQA/DQC/DQR safety light curtains; DQL is for measurement output.

Working Principle

The DQL series uses opposed infrared beams. The emitter sends modulated pulses scanned sequentially; the receiver detects each channel. When an object blocks one or more beams, the controller calculates the blocked-channel count/position and outputs measurement via RS485 (Modbus RTU) or analog 4–20 mA / 0–10 V. Optical synchronization and filtering ensure strong ambient-light immunity; self-diagnostics guarantee reliable data.

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