KEYENCE KV-N Series PLC Modules: KV-N3AM, KV-N8EXT, KV-N24DT,

Technical Dossier

Product Details And Specifications

KEYENCE KV-N Series: Comprehensive Module Range and Technical Overview

The KEYENCE KV-N Series is a compact, high-density programmable logic controller (PLC) platform deployed across global heavy industries including petrochemical refineries, nuclear auxiliary systems, food processing lines, and automotive assembly plants. Its modular backplane architecture allows engineers to configure systems ranging from standalone micro-controllers to distributed I/O networks spanning hundreds of points. The KV-N Series occupies a critical position in mid-range automation infrastructure, particularly in facilities where panel space is constrained and cycle-time determinism is mandatory. Installed base across Asia-Pacific and European process industries remains substantial, making long-term spare parts availability a primary concern for maintenance engineers and procurement teams.

The Evolution of KV-N Series Architecture

The KV-N Series succeeded the earlier KV-700 and KV-1000 platforms, inheriting the high-speed ladder execution engine while introducing a unified USB/Ethernet programming interface and an expanded instruction set compatible with IEC 61131-3 structured text overlays. Early KV-N units (circa 2010–2014) relied on RS-232C and RS-422 serial links for HMI and SCADA integration. From 2015 onward, Ethernet/IP and MODBUS TCP became standard on CPU modules, enabling direct integration with Yokogawa, Honeywell, and Emerson DCS environments without protocol converters. The backplane bus operates at a fixed 10 MHz scan cycle with deterministic interrupt handling down to 0.1 ms, a specification that remains competitive against contemporary micro-PLC offerings. As of 2024, the KV-N Series has entered the mature/end-of-active-production phase for several base unit variants; KEYENCE continues to supply replacement modules through authorized channels, but new project designs are directed toward the KV-8000 platform. This lifecycle status elevates the importance of certified refurbished and new-old-stock (NOS) sourcing for existing installations.

KV-N Series Full Catalog & Functionalities (SKU List)

CPU / Base Units

• KV-N3AM: Compact CPU base unit, 3-slot expansion, built-in USB programming port, 20 kHz high-speed counter input.
• KV-N4AM: 4-slot CPU base unit with dual RS-232C ports and analog I/O option slot.
• KV-N6AM: 6-slot CPU base unit, Ethernet/IP standard, 128k-step program memory.
• KV-N8AM: 8-slot CPU base unit, extended instruction set, supports up to 512 I/O points natively.

Digital I/O Expansion Units

• KV-N8EXT: 8-point digital I/O expansion unit, NPN/PNP selectable, 24 VDC, DIN-rail mount.
• KV-N16EX: 16-point digital input expansion, sink type, 5–24 VDC compatible.
• KV-N16EY: 16-point digital output expansion, transistor source type, 0.5 A per point.
• KV-N32EX: 32-point high-density digital input module, 24 VDC, 40-pin connector.
• KV-N32EY: 32-point high-density digital output module, transistor sink, 40-pin connector.

Analog I/O Modules

• KV-N24DT: 24-point mixed digital I/O with integrated analog conversion, 12-bit resolution, 4–20 mA / 0–10 V selectable.
• KV-NA8V: 8-channel analog voltage input module, ±10 V, 16-bit resolution, 1 ms/ch conversion speed.
• KV-NA4V: 4-channel analog voltage output module, 0–10 V / ±10 V, 12-bit DAC.
• KV-NA4T: 4-channel thermocouple input module, K/J/T/E/R/S/B type, ±0.3°C accuracy.

Communication & Network Adapters

• KV-NE20: Ethernet/IP adapter module, 100BASE-TX, supports explicit and implicit messaging.
• KV-NL20V: CC-Link Ver.2 slave adapter, up to 896 I/O points per station.
• KV-NDP21: PROFIBUS-DP slave module, 12 Mbps, GSD file provided.

Power Supply Units

• KV-N1PU: 24 VDC input power supply unit for KV-N backplane, 5 A output, short-circuit protected.
• KV-N2PU: Dual-rail power supply unit, 100–240 VAC input, redundant output configuration support.

Sourcing Hard-to-Find & Obsolete KV-N Series Parts

DriveKNMS maintains a dedicated inventory program for KV-N Series modules that have been discontinued or placed on restricted allocation by KEYENCE. Our sourcing network spans certified industrial surplus channels across Japan, South Korea, Germany, and the United States, enabling us to fulfill requests for base units, I/O expansion modules, and communication adapters that are no longer available through standard distribution. All units sourced through DriveKNMS are subject to provenance verification: serial number cross-referencing against known production batches, physical inspection for counterfeit indicators (label adhesion, connector pin plating, PCB silkscreen consistency), and functional pre-shipment testing on a KV-N compatible backplane. For facilities operating KV-N installations with a remaining service horizon of 5–15 years, DriveKNMS offers blanket order agreements to reserve critical spare modules against future demand, reducing unplanned downtime risk.

Quality Control for the KV-N Series Range

KV-N Series modules present specific quality control challenges due to their high-density backplane bus connectors and proprietary inter-module communication protocol. DriveKNMS applies the following test protocol to all KV-N units prior to dispatch: (1) Visual inspection under 10× magnification for connector pin deformation, PCB trace corrosion, and capacitor bulge on the power regulation stage. (2) Backplane insertion test on a live KV-N CPU rack to verify module recognition and error-free initialization within the KV STUDIO programming environment. (3) I/O point functional test: each digital input and output point is cycled at 24 VDC; analog channels are verified against a calibrated signal source at 0%, 50%, and 100% of rated range. (4) Communication module validation: Ethernet/IP and serial adapters are tested for packet integrity under continuous polling at rated baud rate for a minimum of 30 minutes. (5) Burn-in soak: modules are powered continuously for 4 hours at ambient temperature before final packaging. Test records are retained and available upon request for quality-critical procurement processes.