Bosch Rexroth DKCXX.3-040-7-FW vs DKC03.3-040-7-FW: Differences & Technical Comparison

Engineers and plant managers working with Bosch Rexroth Indramat drives often encounter part numbers like DKCXX.3-040-7-FW and DKC03.3-040-7-FW. At first glance, these codes look similar, but understanding their difference is crucial for selecting the right servo drive and ensuring compatibility with your automation system. Both are part of the Indramat ECODRIVE03 DKC series – a family of industrial servo drive controllers known for reliability and cost-effectiveness. Wake Industrial stocks a wide range of DKC products and offers comprehensive repair and replacement options. Call 1-919-443-0207 to speak with a representative now and avoid costly downtime!

Overview of the Indramat DKC ECODrive03 Series

Bosch Rexroth’s Indramat DKC ECODRIVE03 series is a line of digital servo drive controllers designed for versatile motion control tasks. These drives are highly regarded for their favorable price/performance ratio and modular design, making them popular in a broad range of industrial applications. The “03” in ECODRIVE03 denotes the generation, reflecting updated features and performance over earlier drives. Key characteristics of this series include ease of installation, high availability, and integrated positioning functions for single or multi-axis control tasks.

Power Classes: DKC ECODRIVE03 units come in several power ratings to suit different servo motor sizes. Standard continuous output current classes are 16 A, 40 A, 100 A, and 200 A for the main variants. Both DKCXX.3-040-7-FW and DKC03.3-040-7-FW belong to the 40 Amp class, meaning they can deliver 40 A continuous current to the motor – suitable for medium power servo axes.

Communication Interfaces: One of the defining features of the DKC series is the variety of control interface options available (denoted by the code before the decimal in the part number). Indramat offered the ECODRIVE03 in multiple interface versions to accommodate different control systems and fieldbus networks:

DKC Option Cards

All these variants share the same basic drive design and power electronics but differ in their communication module or firmware. This modular approach lets you choose a drive that seamlessly integrates with your machine’s control system – whether you are using a traditional +/-10V analog controller, a high-speed digital motion network, or a PLC fieldbus like Profibus or CANopen.

Decoding the Part Numbers.

Before diving into differences, it helps to understand what each segment of the part number signifies:

DKC – Indicates the drive is part of the DKC series of servo drive controllers.

XX.3 or 03.3 – This is the interface and version code. The letters/numbers before the dot denote the interface type (as listed above), and “.3” indicates the hardware series (ECODRIVE03, version 3 hardware). For example, “03.3” specifically means a Profibus-DP interface unit, hardware version 3. “XX.3” is a placeholder used in documentation to mean “any interface version, hardware series 3.” In other words, DKCXX.3 refers to the general family of ECODRIVE03 drives without specifying which interface option is installed.

040 – The current rating in Amps. “040” signifies a 40 A drive.

7 – The voltage class of the drive. In Indramat’s nomenclature, “7” typically corresponds to a three-phase 380–480 VAC supply category that also supports nominal DC bus around 700 V DC.

FW – Stands for Firmware. The drive requires a firmware module that defines its operational firmware and features. In the DKC drives, the firmware is a removable module (often ordered separately) that plugs into the drive controller. Different firmware versions (e.g. for basic drive, positioning control, etc.) can be installed, but “FW” in the part number just denotes that the standard firmware-based configuration is used.

Now, let’s clarify the two specific codes in question:

DKCXX.3-040-7-FW

This is a general designation for a 40 A, 380–480 V class ECODRIVE03 servo drive. The “XX.3” does not pin down the communication interface; it could be any of the available interface versions (Profibus, SERCOS, analog, etc.). Indramat uses the placeholder “DKCxx.3-040-7-FW” in manuals and catalogs to discuss specifications that apply to all 40 A units in the series. For example, a manual might state “DKCxx.3-040-7-FW drives have a DC bus nominal voltage of 700 V DC and support multiple interface options,” applying to all variants in that class. Essentially, DKCXX.3-040-7-FW is not a single unique product, but rather a category reference for any DKC drive of that rating.

DKC03.3-040-7-FW

This is a specific model of DKC drive: the 40 A unit equipped with a Profibus-DP communication interface (as indicated by the “03.3” code). In practice, if you order or have a DKC03.3-040-7-FW, it means the drive comes with the Profibus interface module (often referred to by the option card DKC03.3-LK-PBK02, where PBK indicates Profibus) either installed or as part of its configuration. This model is part of the ECODRIVE03 family and shares the same power electronics as other 40 A drives, but it is intended to be controlled via a Profibus network.

The key difference between DKCXX.3-040-7-FW and DKC03.3-040-7-FW is specificity: the former is a generic label for the family of 40 A drives, while the latter denotes the Profibus-enabled variant of that family. In other words, DKC03.3-040-7-FW is one instance of what would generically be called a DKCXX.3-040-7-FW drive. Functionally, when comparing a particular DKC03.3 unit to another DKCXX.3 unit of the same rating, the communication interface and connectivity are what set them apart. For example, a DKC01.3-040-7-FW (analog interface version of the 40 A drive) and a DKC03.3-040-7-FW (Profibus version) will have the same power handling capability, but one accepts ±10 V analog/±DIN signals while the other connects to a Profibus-DP fieldbus.

It’s worth noting that because the Profibus variant (03.3) includes a fieldbus communication module, it was designed to work in distributed control systems and can handle a broader input voltage range.

Aside from the interface and input range considerations, all DKCXX.3-040-7-FW drives share core attributes. They require a 3-phase AC supply, and internally they generate a nominal ±700 V DC bus for the servo power stage. The drives are modular in hardware – for instance, the firmware module is a removable plug-in card that contains the drive’s operating firmware and parameter memory. This modular firmware design means if you need to update the functionality or replace a corrupted firmware, you can swap the module without replacing the whole drive. Both DKCXX.3 and DKC03.3 units use this concept: the standard firmware defines their features such as operating modes, support for positioning blocks, etc., and must be compatible with the drive hardware.

In summary, DKC03.3-040-7-FW is basically the Profibus DP version of the generic DKCXX.3-040-7-FW drive. If you see “DKCXX.3” in documentation, think of it as “any DKC03/02/04/etc drive of this type” – you’d then identify the exact interface from the actual part number on the unit. For practical purposes, an engineer replacing a drive needs to get the exact match (e.g. Profibus model for a Profibus-controlled system). Installing a different interface variant in place of another would require changes to the control system or firmware. And for more type code breakdowns of DKC and other Bosch Rexroth products be sure to watch our YouTube series. 

Purchasing and Repairing DKC Drives

Having the right drive controller in stock can be mission-critical when your production line is on the line. Wake Industrial specializes in providing fast, reliable access to industrial automation products like the DKC03.3-040-7-FW. Wake Industrial understands that downtime is costly, so we offer rapid quoting and same day shipping to get your operations back up and running as soon as possible.

If you are looking to buy or repair a DKCXX.3-040-7-FW or DKC03.3-040-7-FW drive, Wake Industrial is the source for DKC units.  Wake Industrial stocks Bosch Rexroth Indramat drives, motors, accessories, and offers repair services for these units  (Wake Industrial is not an authorized Bosch Rexroth distributor). Wake Industrial has a wealth of DKC drives in stock, ready to ship with quick turnaround, which means your down time is minimized when you need to get a production line back up and running.

Don’t hesitate, get the Wake Industrial Advantage by calling 1-919-443-0207 or emailing sales@wakeindustrial.com today to get a quote back within 15 minutes during business hours.