Connection

WARNING

Risk of injury through electric shock and damage to the device!

Bring the Bus Terminals system into a safe, de-energized state before starting mounting, disassembly or wiring of the Bus Terminals!

Connection 1:
Connection

Terminal point

No.:

Connection for

Comment

L1

1

Phase L1

Connections for the voltage measurement. (See note under Make sure terminal point N is zeroed or grounded!)

L2

2

Phase L2

L3

3

Phase L3

N

4

Neutral conductor N (internally connected to terminal point IN,
capacitively connected to the grounding contact for the mounting rail)

IL1

5

Current transformer at L1

Connections for the current transformers. (See note under Operate the current transformer as intended!)

IL2

6

Current transformer at L2

IL3

7

Current transformer at L3

IN

8

Star point of the current transformers
(internally connected to terminal point N,
capacitively connected to the grounding contact for the mounting rail)

*) The KL3403-0026 has no capacitive connection to the grounding contact of the mounting rail!

CAUTION

Make sure terminal point N is zeroed or grounded!

If you do not connect the terminal point N with the neutral conductor of your mains supply (e.g. if the KL3403 is used purely for current measurements), terminal point N should be earthed, in order to avoid dangerous overvoltages in the event of a current transformer fault!

CAUTION

Operate the current transformer as intended!

Please note that many manufacturers do not permit their current transformers to be operated in no-load mode! Connect the KL3403 to the secondary windings of the current transformers before using the current transformer!

UL compliance

Follow the instructions indicated below, in order to comply with the specifications of Underwriters Laboratories.

CAUTION

Connection 2:

Intended use

The terminals are exclusively intended for application with the UL-listed I/O systems of the series BKxxxx, BCxxxx, BXxxxx, LCxxxx, CXxxxx, KLxxxx, KSxxxx or KMxxxx from Beckhoff.

CAUTION

Connection 3:

cULus verification

For the cULus verification, the Beckhoff I/O system only examined for risk of fire or electric shock (in accordance with UL508 and CSA C22.2 No. 142).

CAUTION

Connection 4:

Phase voltage according to UL specifications 300 V max.

The maximum phase voltage of 500 V described in the technical data should be limited to 300 V for applications requiring UL approval.

CAUTION

Connection 5:

Current transformer

Current measurement inputs with the IDs IL1, IL2, IL3, N may only be connected to isolating current transformers, which limit the available current to max. 5 A, 20 V.

CAUTION

Connection 6:

No extended temperature range

The limited temperature range applies, if the KL3403-0000 / KS3403-0000 are used according to UL conditions (see Technical data).