FT-R40
AI

The **FT-R40** is a specific diffuse reflective photoelectric sensor head from Keyence’s **Tuff-Sensor** fiber optic series. It is not an active electronic device on its own; rather, it is a passive optical component designed to work in conjunction with a separate fiber optic amplifier (such as the FS-N series).
Below is a breakdown of its electronic and structural components.
### 1. Technical Specifications
The FT-R40 is categorized as a **Threaded Fiber Unit**. Its electronic performance depends heavily on the amplifier it is paired with.
| Feature | Specification |
| :--- | :--- |
| **Fiber Type** | Diffuse Reflective (Emitter and Receiver in one head) |
| **Housing Material** | Stainless Steel (SUS303) |
| **Minimum Bend Radius** | R1 mm (High-flexibility fiber) |
| **Fiber Diameter** | ø1.0 mm × 2 |
| **Detection Distance** | Varies by amplifier (e.g., 20mm to 120mm typical) |
| **Ambient Temperature** | -40 to +70 °C |
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### 2. Core Electronic Components & Structure
Since the FT-R40 is a fiber optic sensor head, its "electronics" are primarily focused on light transmission rather than integrated circuitry.
#### A. The Optical Fibers (Cores)
Inside the protective cladding, there are two distinct plastic fiber cores:
* **Transmitting Fiber:** Carries the modulated light (usually red LED or Laser) from the amplifier to the target.
* **Receiving Fiber:** Captures the light reflected off the object and returns it to the amplifier's photodiode.
#### B. The Sensor Head (Tip)
The tip is a threaded stainless steel bolt (M4 size). This housing ensures:
* **Precision Alignment:** The two fibers are held at a fixed distance and angle to optimize the "sensing spot."
* **Durability:** Protects the delicate fiber ends from mechanical stress and industrial environments.
#### C. The Fiber Optic Interface
The end of the cable that plugs into the amplifier is polished to ensure maximum light coupling. The electronic signal conversion (Light $\rightarrow$ Voltage) happens inside the **Amplifier Unit**, not the FT-R40 head itself.
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### 3. Compatible Amplifier Units
To make the FT-R40 functional, it must be connected to an electronic amplifier. These units handle the logic and output:
1. **FS-N40 Series:** Digital CMOS amplifiers.
2. **FS-V30 Series:** High-speed dual-digital display amplifiers.
3. **Output Logic:** These amplifiers provide the NPN or PNP transistor outputs based on the light intensity received back through the FT-R40.
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### 4. Installation Considerations
* **Cutting the Fiber:** The FT-R40 comes with a specific fiber cutter. Because the electronic accuracy depends on light transmission, a jagged cut at the amplifier end will cause "light leakage" and signal instability.
* **Bend Radius:** While it features a "Tuff-Flex" R1 mm radius, repeated bending beyond its limits will fracture the internal plastic cores, leading to a permanent loss of signal.
- ⤷
What is the maximum sensing distance of the FT-R40 when used with an FS-N41 amplifier?
- ⤷ How does a diffuse reflective sensor differ from a thrubeam sensor in this series?
- ⤷ Can the FT-R40 be used in high-temperature environments above 70°C?