LD-200 / LD-202 Dual Channel Vehicle Loop Detector

The JUTAI LD-200 / LD-202 is a dual-channel inductive vehicle loop detector designed for parking barrier gates, vehicle entrance and exit control, access control systems and traffic management applications.

Unlike a single-channel detector, the dual-channel design can connect two independent inductive loops, CH1 and CH2, allowing one detector to monitor two vehicle detection zones. The two-loop configuration also supports vehicle direction detection, making the detector particularly suitable for parking entrances, exits and bidirectional vehicle lanes.

The detector provides configurable presence and pulse relay outputs, eight sensitivity levels for each channel, four selectable operating frequency levels and six operating modes for different parking and traffic control requirements.

Key Features

Dual Channel Vehicle Detection

LD-200 / LD-202 supports two independent loop inputs:

• CH1 Loop
• CH2 Loop

Both channels can detect vehicles independently, allowing one detector to perform the functions normally requiring two separate single-channel detection circuits.

This makes it suitable for:

• Parking entrance and exit lanes
• Barrier gate control
• Vehicle presence detection
• Direction recognition
• Traffic control
• Vehicle passage logic

Vehicle Direction Detection

One of the key advantages of the dual-loop design is direction detection.

Two loops can be installed sequentially in the vehicle travel path.

For example:

CH1 → CH2

can be interpreted as one travel direction, while:

CH2 → CH1

can be interpreted as the opposite direction.

This allows the controller to distinguish vehicle entry and exit movements and generate the corresponding CH1 or CH2 relay output according to the selected operating mode.

The manual provides several direction-detection modes based on the sequence in which vehicles enter and leave CH1 and CH2.

Six Selectable Working Modes

The detector provides six operating modes for different control requirements.

Mode 1 — Direction Pulse Detection

Detects the sequence between CH1 and CH2 and produces a relay pulse after the vehicle leaves the corresponding loop.

Mode 2 — Direction Presence Detection

Uses the two-loop sequence to determine direction and generates a presence output according to the selected travel direction.

Mode 3 — Alternative Direction Presence Logic

Provides another dual-loop direction-control logic for applications requiring different vehicle entry and exit output timing.

Mode 4 — Independent Two-Channel Detection

CH1 and CH2 operate as separate vehicle presence detection channels.

This mode is useful when two independent loops need to be monitored without direction detection.

Mode 5 — Entry Pulse Detection

When a vehicle enters CH1 or CH2, the corresponding relay generates a pulse output.

Mode 6 — Exit Pulse Detection

The corresponding relay generates a pulse after the vehicle leaves CH1 or CH2.

This flexible mode structure allows the same detector to be used for both simple dual-loop detection and more advanced vehicle direction applications.

8-Level Independent Sensitivity Adjustment

Each channel provides 8 selectable sensitivity levels.

This allows the installer to adjust CH1 and CH2 according to:

• Loop size
• Vehicle type
• Installation conditions
• Required detection sensitivity

The manual also provides a special sensitivity increase function for applications such as trailers, where stable presence detection is important.

20–100kHz Adjustable Frequency

The operating frequency can be adjusted from approximately 20kHz to 100kHz using four selectable frequency levels:

• High
• Medium-High
• Medium-Low
• Low

Frequency adjustment is useful when multiple loops are installed close to each other because different frequency settings can help reduce interference between adjacent detection loops.

Automatic Reset and Permanent Presence

The detector supports two vehicle-presence behaviors.

Permanent Presence Mode

A detected vehicle can remain continuously present without automatic reset until the vehicle leaves the loop or the detector is manually reset.

Automatic Reset Mode

In Normal Mode, the detector automatically resets after approximately 10 minutes of continuous vehicle presence.

This can help recover from abnormal or unintended long-duration detection conditions.

Technical Specifications

Typical Applications

Parking Barrier Gates

Detects vehicles approaching, passing through or leaving a parking barrier gate and provides signals to the barrier controller.

Parking Entrance and Exit Direction Detection

Two loops installed sequentially can distinguish vehicle travel direction according to the CH1/CH2 detection sequence.

Two Independent Vehicle Detection Zones

When direction detection is not required, CH1 and CH2 can operate as two separate presence channels.

Vehicle Access Control

Can provide vehicle presence or pulse signals to compatible access-control and gate-control equipment.

Parking Counting and Traffic Logic

The CH1 → CH2 or CH2 → CH1 sequence can be used by the connected control system for vehicle flow and direction logic.

Loop Installation

The manual recommends configuring loop turns according to the total loop perimeter:

For a typical dual-loop direction-detection installation, the manual illustrates CH1 and CH2 as two separate loops placed along the vehicle travel path, with approximately 1m spacing between the two detection loops.

Why Choose a Dual Channel Loop Detector?

Compared with a single-channel vehicle detector, the LD-200 / LD-202 provides several important advantages:

• One detector supports two inductive loops
• Supports vehicle direction detection
• CH1 and CH2 can also work independently
• 8 sensitivity levels for each channel
• 6 configurable operating modes
• Presence and pulse output options
• 20–100kHz frequency adjustment
• Automatic reset and permanent presence modes
• Suitable for entrance and exit vehicle control

For parking system integrators, this makes the dual-channel detector particularly useful where two loops, vehicle direction recognition or more flexible barrier-control logic are required.

• Power LED (RED): Illuminates to indicate "Power ON"
• CH1 Detection LED:
  • Steady On: Vehicle detection
  • Slow Blinking: Loop short circuit or insufficient twists
  • Fast Blinking: Loop open circuit or excessive twists
• CH2 Detection LED:
  • Steady On: Vehicle detection
  • Slow Blinking: Loop short circuit or insufficient twists
  • Fast Blinking: Loop open circuit or excessive twists

Sensitivity and frequency adjustment is facilitated through 7-way and 10-way dip switch settings:

• 8 different sensitivity settings available via dip switch configuration
• Dip switches 6, 7, and 8 govern CH1 sensitivity (0.8 to 0.015)
• Dip switches 3, 4, and 5 control CH2 sensitivity (0.8 to 0.015)

Switch 1 (S1) - Channel 1 Loop Function Selection:

• DIP 1 & DIP 2: Special Sensitivity Increase For Both Trailer (Both Channels)
• D3, D4, D5 and Switch 2 D1, D2: Special Functions (Mode1, 2, 3 Direction Detection. Mode 4, 5, 6 Normal mode)
• D6 & D7 & D8 and Switch 2 D3 & D4 & D5: CH1 and CH2 Sensitivity Selection (Eight Levels)
• D9 & D10 and Switch2 D6, D7: Frequency Selection (20 K to 100 KHz)

• Coil cutting size should be rectangle: length 1.0 to 2.0 meters, width 0.8 to 1.2 meters
• Avoid right angles at corners as much as possible
• Use ferromagnetic wires for induction coil, total length up to 500 meters
• Keep product plug and socket in vertical direction during installation

The JUTAI LD200/202 double-channel vehicle loop detector series, equipped with direction recognition function, is ideal for single-channel entry and exit scenarios when integrated with:

• JUTAI One door controller (Model: AC-11)
• JUTAI gate barrier (Model: BR-110)
• JUTAI long-range RFID reader (Model: PUHF-9)
• High-temperature resistance loop coils (Model: JTHT-11)

The JUTAI LD-200/202 Double Channel Loop Detector can also function as two independent single-channel loop detectors, suitable for standard one-in and one-out parking lots.

This configuration provides cost-saving benefits by reducing hardware costs associated with using separate detectors for each function.