Photoelectric light curtain designed for vehicle separation, counting and classification at tolls, WIM, intersections and traffic monitoring sites. Resolutions 20/40/80 mm; protective height H=(n−1)×K; typical detection range 0.3–15 m (options up to 0.3–40 m); optical synchronization, fast response, strong anti-interference. Dual-channel NPN/PNP (NO/NC) plus RS485 option. Optional heated outdoor enclosure for snow and low-temperature scenarios.
Data summarized from the provided DQLV manual sheets. If discrepancies occur, the official datasheet prevails.
Resolution & Selection Guide
Resolution (K)
Typical Application
20 mm
Precise vehicle head detection, separation & counting
40 mm
Standard vehicle presence & classification
80 mm
Wide openings / long-range presence
Protective height H = (n − 1) × K. Overall length for DQLV L = P + H + J + 18 + 18. P/J depend on resolution (see tables below).
Technical Parameters (DQLV Series)
Category
Item
Typical Value / Option
Notes
Optical
Operating principle
Through-beam IR LED, modulated
Emitter/receiver pair with filtering & anti-jamming
Resolution (K)
20 / 40 / 80 mm
Vehicle separation, counting, classification
Protective height (H)
H = (n−1) × K
n = number of beams
Response time
≤ 15 ms
Depends on beam count
Detection range
0.3–15 m (typ.)
Options up to 0.3–40 m
Ambient immunity
High sunlight immunity
Flicker & stray-light suppression
I/O & Power
Supply
DC 12–24 V (controller AC 110–220 V optional)
Reverse/over-voltage protection
Outputs
Dual-channel NPN / PNP, NO/NC selectable
Plus RS485/232 communication option
Protection
Short / over-current / over-load
Auto recovery
Indicators
Power / All-clear / Blocked LEDs
Front window indication
Sync
Optical synchronization
Stable wiring
Cable length
3.5 m / 5 m / 10 m / 15 m
Factory-selectable
Ingress protection
IP65 (sensor)
Heated housing NEMA 3R / IEC IP54
Heated Outdoor Enclosure (Option)
Power
24 V / 10 A
Automatic heating & humidity control
Controllers
Main 4 °C off / 29 °C on; Backup 55 °C off / 36 °C on
Panel-sealed thermostats
Materials
Stainless steel / aluminum; heated glass window
Anti-fog, anti-frost
Env. range
Typical −20 °C ~ +70 °C
For rainy/snowy/low-temp sites
DQLV Series Detailed Specifications
Model format: DQLV-K-NN-H. Example: DQLV-40-04-120 (K=40, n=4, H=120). P/J from the dimension sheet; overall length uses L = P + H + J + 36 (18 mm allowance at both ends).
K (mm)
Beams n
Protective Height H (mm)
P/J (mm)
Overall Length L (mm)
Model Example
Range
20
4
60
10/25
131
DQLV-20-04-60
0.3–15 m (typ.)
20
6
100
10/25
171
DQLV-20-06-100
0.3–15 m (typ.)
20
8
140
10/25
211
DQLV-20-08-140
0.3–15 m (typ.)
20
10
180
10/25
251
DQLV-20-10-180
0.3–15 m (typ.)
20
12
220
10/25
291
DQLV-20-12-220
0.3–15 m (typ.)
20
14
260
10/25
331
DQLV-20-14-260
0.3–15 m (typ.)
20
16
300
10/25
371
DQLV-20-16-300
0.3–15 m (typ.)
20
18
340
10/25
411
DQLV-20-18-340
0.3–15 m (typ.)
20
20
380
10/25
451
DQLV-20-20-380
0.3–15 m (typ.)
20
22
420
10/25
491
DQLV-20-22-420
0.3–15 m (typ.)
20
24
460
10/25
531
DQLV-20-24-460
0.3–15 m (typ.)
20
26
500
10/25
571
DQLV-20-26-500
0.3–15 m (typ.)
20
28
540
10/25
611
DQLV-20-28-540
0.3–15 m (typ.)
20
30
580
10/25
651
DQLV-20-30-580
0.3–15 m (typ.)
20
32
620
10/25
691
DQLV-20-32-620
0.3–15 m (typ.)
20
34
660
10/25
731
DQLV-20-34-660
0.3–15 m (typ.)
20
36
700
10/25
771
DQLV-20-36-700
0.3–15 m (typ.)
20
38
740
10/25
811
DQLV-20-38-740
0.3–15 m (typ.)
20
40
780
10/25
851
DQLV-20-40-780
0.3–15 m (typ.)
20
42
820
10/25
891
DQLV-20-42-820
0.3–15 m (typ.)
20
44
860
10/25
931
DQLV-20-44-860
0.3–15 m (typ.)
20
46
900
10/25
971
DQLV-20-46-900
0.3–15 m (typ.)
20
48
940
10/25
1011
DQLV-20-48-940
0.3–15 m (typ.)
20
50
980
10/25
1051
DQLV-20-50-980
0.3–15 m (typ.)
20
52
1020
10/25
1091
DQLV-20-52-1020
0.3–15 m (typ.)
20
54
1060
10/25
1131
DQLV-20-54-1060
0.3–15 m (typ.)
20
56
1100
10/25
1171
DQLV-20-56-1100
0.3–15 m (typ.)
20
58
1140
10/25
1211
DQLV-20-58-1140
0.3–15 m (typ.)
20
60
1180
10/25
1251
DQLV-20-60-1180
0.3–15 m (typ.)
20
62
1220
10/25
1291
DQLV-20-62-1220
0.3–15 m (typ.)
20
64
1260
10/25
1331
DQLV-20-64-1260
0.3–15 m (typ.)
20
66
1300
10/25
1371
DQLV-20-66-1300
0.3–15 m (typ.)
20
68
1340
10/25
1411
DQLV-20-68-1340
0.3–15 m (typ.)
20
70
1380
10/25
1451
DQLV-20-70-1380
0.3–15 m (typ.)
20
72
1420
10/25
1491
DQLV-20-72-1420
0.3–15 m (typ.)
For long lanes select range variants up to 0.3–40 m. Keep the model format DQLV-K-NN-H.
Typical Applications
Toll lanes / ETC / toll plazas: vehicle separation and anti-tailgating; reliable head detection.
Weigh-in-Motion (WIM) & traffic statistics: counting, presence and classification with RS485 integration.
Intersections / access control / logistics gates: long-range presence, queue monitoring and alarm output.
Harsh outdoor sites: add the heated enclosure to maintain clear optics in rain, snow and low temperatures.
When selecting range variants (A…H), choose according to lane width and installation height; for >5 m please specify in advance.
Frequently Asked Questions
What is a vehicle separation light curtain and how does it work?
It is a through-beam photoelectric barrier with paired emitter and receiver columns that project a grid of modulated infrared beams across a lane. When a vehicle interrupts the beams, the DQLV detects presence, separates tail-gating vehicles and counts axles or bodies. With 20/40/80 mm resolution it suits tolling, WIM and traffic-counting sites.
What resolution should I choose: 20, 40 or 80 mm?
Choose by how fine the detection must be. 20 mm gives precise vehicle-head detection, separation and counting; 40 mm covers standard vehicle presence and classification; and 80 mm suits wide openings or long-range presence. Protective height follows H=(n−1)×K, so beam count and resolution together set the curtain height you order.
How far can the DQLV detect, and is it usable outdoors?
Typical builds detect 0.3–15 m, with selectable options of 0.3–3/6/10/15/20/25/30/40 m up to 40 m. For rain, snow and low-temperature sites, add the optional heated outdoor enclosure with automatic heating, humidity control and anti-fog glass, rated NEMA 3R / IEC IP54; the sensor itself is IP65.
What outputs and communication does the DQLV provide?
The DQLV gives dual-channel NPN/PNP outputs, NO/NC selectable, for direct wiring to a PLC, counter or controller, plus an optional RS485/232 serial interface for traffic statistics and integration. Front-window LEDs show power, all-clear and blocked status. Supply is DC 12–24 V, with an AC 110–220 V controller option.
How is the DQLV model number and overall length determined?
Models use the format DQLV-K-NN-H, for example DQLV-40-04-120 (K=40 mm, n=4 beams, H=120 mm). Protective height is H=(n−1)×K, and overall length is L = P + H + J + 36, allowing 18 mm at each end. P and J depend on the chosen resolution; see the detailed dimension tables on this page.
