KEBA DO321 | Digital Output Module

Description

Core Product Summary (Brand / Model / Key Attributes)

The KEBA DO321 (commonly supplied as DO321/B) is a digital output module manufactured by KEBA for industrial automation systems. It functions as an I/O interface card that switches 24 V DC control signals to field actuators, relays, and other discrete devices. The module is widely referenced in the context of KEBA control platforms and Engel injection molding machines.

It accepts 24 V DC supply from the front terminals (19.2 V to 30 V in accordance with IEC 61131-2) as well as from the K-Bus (24 V and 5 V). Addressing is performed via a 16-position address switch located on the side of the module. Field connections use open terminals on a 5.08 mm grid. Maximum power consumption on the K-Bus is specified as 2.1 W at 24 V and 0.4 W at 5 V. The module is classified under overvoltage category II and equipment class III according to EN 61131-2:2007.

Key Technical Specifications

Detailed Product Overview

The KEBA DO321 is a modular digital output card designed to interface a higher-level KEBA controller with discrete field devices. It converts binary control commands into switched 24 V DC signals that drive actuators, solenoids, indicator lamps, and similar loads commonly found on plastics processing machinery and other automated equipment.

In Engel injection molding machines the module appears as a rack-mounted I/O card that handles digital signal exchange between the machine controller and peripheral devices such as hydraulic valves, safety interlocks, and process sensors. Power can be taken either from dedicated front-side terminals or shared via the K-Bus backplane, allowing flexible system architectures. The side-mounted address switch enables multiple modules of the same type to be uniquely identified on a single K-Bus line.

Terminal blocks use a standard 5.08 mm pitch open-style design for straightforward field wiring. The module conforms to the electrical safety and environmental requirements of EN 61131-2 for programmable controllers, including the stated overvoltage category and equipment class. Because official manufacturer documentation for this specific older-generation part is limited in public channels, exact channel count, per-channel current rating, and diagnostic features should be confirmed against the physical unit or the original machine documentation.

DO321

DO321

System Compatibility & Integration Requirements

No official successor or migration path is documented in publicly available materials for this specific model.

Engineering Selection Highlights

• Confirm the exact suffix (/B or /16/B) and any internal part number (e.g., 21490) printed on the existing module before ordering a replacement.
• Verify that the host system uses the KEBA K-Bus architecture and that the required address range is available.
• Match the 24 V DC supply arrangement (front terminals or K-Bus) to the machine’s power distribution design.
• Ensure the field wiring terminals and pitch (5.08 mm) are compatible with existing cabling and terminal blocks.
• Check physical form factor and mounting style against the card cage or rack used in the target machine (commonly Engel presses).
• Treat the module as a system-specific spare; interchangeability with later KeConnect-series digital output modules cannot be assumed without verification.

Dimensions, Mounting & Connection Notes

Approximate external dimensions reported by suppliers are 12.7 cm × 24.8 cm × 20.3 cm with a weight of approximately 0.4 kg (values may include packaging or represent typical rack-module size). The module is designed for installation in a compatible KEBA card cage or rack. Field wiring uses open-style terminals on a 5.08 mm grid. Exact mounting orientation, clearance requirements, and torque values are not published in the available secondary references and should be taken from the original machine documentation or measured from the installed unit.

FAQ

What is the KEBA DO321?
It is a digital output module from KEBA that switches 24 V DC signals to field devices in industrial control systems, frequently used on Engel injection molding machines.

What is the difference between DO321 and DO321/B?
DO321/B is the most commonly listed variant of the DO321 digital output module. Both designations refer to the same functional family of K-Bus output cards.

What supply voltage does it require?
24 V DC supplied either from the front terminals (19.2 V to 30 V per IEC 61131-2) or from the K-Bus (24 V and 5 V rails).

How is the module addressed?
A 16-position rotary or DIP-style address switch located on the side of the module sets the K-Bus address.

What type of field connections does it use?
Open terminals with 5.08 mm pitch.

Is official documentation still available?
Publicly accessible full datasheets for this older module are limited. Identification and replacement should be based on the markings of the existing unit and the machine’s original documentation.

Can it be used outside Engel machines?
It is a KEBA K-Bus module and can be used in any compatible KEBA control system that supports the same bus and power architecture, subject to verification of address range, power budget, and mechanical fit.