FS-N42N Keyence FS-N40 Fiber Optic Sensor Amplifier

FS-N42N Keyence FS-N40 Digital Fiber Optic Sensor Amplifier (NPN, Expansion Unit)

Key Technical Specifications

• Brand: Keyence; Model: FS-N42N; Series: FS-N40
• Unit role: expansion unit with one NPN control output
• Output type: open-collector, 30 V max, 100 mA max per output
• Response time options: 23 µs (S-HSPD) through 64 ms (TERA)
• Light source: red four-element LED at 660 nm wavelength
• Supply voltage: 10 to 30 VDC with 10% ripple P-P or less
• Power consumption: 870 mW or less (34 mA at 24 V)
• ECO modes lower draw to 800 mW (ECO ON) and 710 mW (ECO FULL)
• Weight: approximately 48 g; cable type connection

Performance and Environmental Tolerance

• Eight selectable response speeds cover high-speed and slow-response applications.
• The 23 µs setting suits small-part detection and fast registration tasks.
• The 64 ms setting stabilizes readings on low-contrast or moving targets.
• Operating temperature range spans -20 to +55 °C without freezing.
• Thermal limits derate as you add more units to the chain.
• Residual voltage stays at 1.4 V at 10 mA for clean signal transfer.
• Residual voltage reaches 2 V across the 10–100 mA load range.
• Stable LED output resists ambient light interference in production areas.

Expansion and Installation Guide

• Link the expansion unit to a main amplifier before powering the system.
• Combine up to 16 expansion units for 17 amplifiers in total.
• A dual-output model counts as two units within the expansion limit.
• Mount the cable-type unit on a DIN rail or bracket near the sensing point.
• Feed the unit from a 10–30 VDC Class 2 or LPS supply.
• Hold supply ripple at 10% P-P or less to protect measurement stability.
• Keep output wiring separate from high-current lines to reduce noise.
• Review parameters on the OLED display after each channel change.

Package Contents

• 1 × Keyence FS-N42N expansion amplifier unit
• 1 × Instruction manual
• 1 × Mounting bracket and hardware set
• Protective packaging for safe transport
• Shipping via FedEx, UPS, or DHL

Frequently Asked Questions

• Q: Can the FS-N42N work without a main unit?
  A: No, this expansion unit needs a main amplifier such as the FS-N41N to operate and display settings.
• Q: How many units can I chain together?
  A: You can connect up to 16 expansion units, giving 17 amplifiers total. A dual-output unit counts as two.
• Q: Which response time fits my application?
  A: Choose 23 µs for high-speed detection and 64 ms for stable readings on difficult targets.
• Q: What supply voltage does this amplifier require?
  A: It runs on 10 to 30 VDC with ripple at 10% P-P or less, using a Class 2 or LPS source.
• Q: Does the FS-N42N provide external inputs?
  A: No, this expansion unit has no external input and offers one NPN control output.
• Q: What is the operating temperature range?
  A: The unit works from -20 to +55 °C without freezing, with derating as you add units.
• Q: How much does the amplifier weigh?
  A: The FS-N42N weighs approximately 48 g, lighter than the main unit.
• Q: Is stock available and how fast do you ship?
  A: Yes, we hold new original stock and ship within 5 days via DHL, FedEx, or UPS.
• Q: What is your return policy?
  A: We accept returns within 30 days of delivery.