Keyence FS-N43N Dual Output Sensor Amplifier

Keyence FS-N43N Dual Output Digital Fiber Sensor Amplifier

The Keyence FS-N43N is the main unit of the FS-N40 series. It carries two NPN control outputs and one external input. Because it is a main unit, it supplies power and control signals to connected expansion amplifiers. Engineers pick the FS-N43N when a line needs two independent detection channels plus synchronized timing control.

Technical Specifications

A red four-element LED with a 660 nm wavelength drives the optical system. This design keeps emission strong across the full fiber length. The amplifier offers eight response modes, from 23 µs (S-HSPD) to 64 ms (TERA). Therefore, one model covers high-speed registration marks and slow, dusty targets.

• Response time: 23 µs (S-HSPD) / 50 µs (HSPD) / 250 µs (FINE) / 500 µs (TURBO) / 1 ms (SUPER) / 4 ms (ULTRA) / 16 ms (MEGA) / 64 ms (TERA)

• Control outputs: 2 (NPN open-collector)

• External input: 1, input time 2 ms (ON) / 20 ms (OFF) or longer

• Output rating: 30 V max, 100 mA max per output

• Residual voltage: 1.4 V at 10 mA; 2 V at 10–100 mA

• Unit expansion: up to 16 units (17 total including main; dual-output counts as 2)

Electrical and I/O Details

The supply voltage spans 10 to 30 VDC with 10% ripple P-P or less. A Class 2 or LPS source is required. Power consumption stays at 870 mW or less, which equals 34 mA at 24 V. With ECO ON it falls to 800 mW, and ECO FULL brings it to 710 mW. Additionally, the external input accepts a bank-switching or timing signal from a PLC. This feature lets users switch settings without touching the display.

Mechanical and Environmental Parameters

The main unit weighs approximately 83 g, which is heavier than the expansion model due to the built-in power circuit. Operating temperature ranges from -20 to +55 °C with no freezing. Furthermore, thermal derating applies as users add expansion units. The housing fits standard DIN rail mounting inside a control cabinet.

Installation Guide

First, clip the main unit onto the DIN rail at the left end of the amplifier group. Next, wire the 10–30 VDC supply and the two NPN outputs to the PLC. Then, connect the external input if the application needs bank switching. After that, attach expansion units to the right side through the expansion connector. Finally, set the response mode and thresholds through the OLED display, and run a test with the actual workpiece.

Keep the fiber bend radius within the manufacturer limit and route cables away from high-voltage lines. For long output runs, check the voltage drop against the load tolerance.

Packaging List

• 1 × Keyence FS-N43N main amplifier unit

• 1 × Mounting bracket

• 1 × Instruction sheet

FAQ

Q1: What makes the FS-N43N different from an expansion unit?
A: The FS-N43N is a main unit. It has its own power supply circuit and two control outputs. Expansion units such as the FS-N42N need a main unit to operate.

Q2: How many expansion units can I connect?
A: You can add up to 16 expansion units for 17 total amplifiers. A dual-output model counts as two units, so plan the count carefully.

Q3: What is the external input used for?
A: The external input supports bank switching and timing functions. It responds to signals of 2 ms ON and 20 ms OFF or longer.

Q4: Which response mode fits my application?
A: Choose 23 µs for high-speed detection. Use 4 ms or slower modes when targets move slowly or when dust and vibration affect stability.

Q5: How do you ship this product?
A: We ship by Fedex, UPS, or DHL. Orders usually leave the warehouse within 1–3 business days after payment confirmation.