D2-16ND3-2

What function does this module perform?

It receives discrete ON/OFF signals from field devices and transfers their states to a compatible PLC system. Typical input devices include proximity sensors, limit switches, selector switches and push-buttons.

How many discrete input points are provided?

The module provides 16 discrete input points, allowing up to 16 compatible field signals to be monitored.

Which PLC platform is this module designed for?

The D2-16ND3-2 is designed for use within the Koyo DirectLogic DL205 modular PLC platform. Base, controller and system configuration compatibility should be checked before installation.

Can it be used with both sinking and sourcing field signals?

Yes. Its sink/source input design allows connection to compatible NPN or PNP-style DC field devices when the commons and signal conductors are wired correctly.

How are the inputs grouped?

The 16 inputs are arranged as two groups of eight points, with a separate common connection for each group. This provides greater flexibility when arranging field wiring.

Does the module control field devices directly?

No. This is an input module, so it monitors signals rather than switching loads. A suitable discrete output module is required to operate devices such as relays, contactors, lamps or solenoid valves.

What do the front indicators show?

The front status indicators provide a visual representation of the logical state of individual inputs. An illuminated indicator normally shows that the corresponding input has been recognised as ON.

What types of applications commonly use this module?

Common applications include machine-state monitoring, conveyor sensing, packaging equipment, material-handling systems, process skids and general factory automation.

What should be checked before replacing an existing module?

Confirm the module reference, DL205 base compatibility, field-signal voltage, sink/source arrangement, common-terminal layout, slot assignment and terminal wiring. The installation should be de-energised before the module or terminal block is removed.

Can existing field wiring be retained during replacement?

It may be possible to retain the existing wiring when the replacement has the same terminal arrangement and electrical requirements. Every terminal designation and common connection should still be verified before energising the system.

How does the PLC access the input states?

The controller reads the module as discrete input data associated with its position in the DL205 base. The exact input addresses depend on the controller, slot location and I/O configuration.

Why is correct common-terminal wiring important?

The common connections establish the required current path for each group of inputs. Incorrect polarity or common wiring can prevent signals from registering and may expose the module to unsuitable electrical conditions.