BK1250

What is this compact coupler used for?

This compact bus coupler connects EtherCAT E-bus terminals with standard K-bus terminals, allowing established KL-series I/O modules to be integrated into an EtherCAT terminal system.

Which communication protocol does the coupler use?

The BK1250 uses the EtherCAT protocol and supports a communication rate of 100 Mbaud.

How many K-bus terminals can be connected?

Up to 64 K-bus terminals can be connected directly. This can be expanded to as many as 255 terminals using the appropriate K-bus extension interfaces.

What power supply does the unit require?

The coupler requires a nominal 24 V DC supply with a permitted tolerance of -15% to +20%.

How much K-bus current can the coupler supply?

The BK1250 provides a maximum K-bus supply current of 500 mA at 5 V. The total current requirement of the connected terminals should be checked during system design.

What is the maximum fieldbus data capacity?

The coupler supports up to 1,024 bytes of input data and 1,024 bytes of output data. It can accommodate up to 8,192 digital peripheral signals or 256 analog peripheral signals, subject to the connected terminal arrangement.

How is the coupler mounted?

It mounts on a standard 35 mm DIN rail that conforms to EN 60715. The terminal components should be joined using their tongue-and-groove guides so that the internal bus contacts engage correctly.

What are the approximate dimensions and weight?

The unit measures approximately 15 mm wide, 100 mm high, and 70 mm deep. Its aligned width is approximately 12 mm, and it weighs about 55 g.

What operating temperatures are permitted?

The permitted ambient operating range is -25°C to +60°C (-13°F to +140°F). The storage range is -40°C to +85°C (-40°F to +185°F), with relative humidity up to 95% and no condensation.

What level of environmental protection does the enclosure provide?

The coupler has an IP20 rating. It is intended for installation inside a suitable industrial control cabinet and does not provide protection against water.

Does the unit provide electrical isolation?

Yes. It provides 500 V electrical isolation between the power contacts, supply voltage, and communication side.

What are the ratings of the power contacts?

The power contacts are rated for a maximum of 24 V DC and 10 A. Their potential arrangement must be considered alongside the requirements of the connected I/O terminals.

Can the coupler be installed in different orientations?

Yes, the installation position is variable. A horizontal DIN rail with the terminal connection surfaces facing forward is generally preferred because it supports effective convection cooling.

What do the indicator LEDs show?

The front indicators provide status information for the E-bus connection, operating state, K-bus activity, K-bus errors, I/O condition, and power-contact supply, helping personnel identify common connection or terminal-chain issues.

What should be checked when replacing an existing unit?

Confirm the terminal sequence, total K-bus current demand, supply wiring, power-contact potential groups, device revision, and parameter settings. The replacement should be installed with the system de-energized and the complete terminal assembly correctly engaged on the DIN rail.