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4-channel digital input terminal, Safety

4-channel digital input terminal, Safety

The AKT2G-SDI-004 is a digital input terminal with 4 fail-safe inputs. With two-channel connection, the this meets the requirements of IEC 61508:2010 SIL 3,DIN EN ISO 13849-1:2015 (Cat 4, PL e), UL508, UL1998 and UL991.

Product available worldwide


Please refer to the KAS webhelp for important information regarding the application and use of safety rated I/O terminals.

Technical Data AKT2G-SDI-004
Number of inputs 4
Status Display

4 (one green LED per input)

Reaction time (read input/write to E-bus)

typically: 4 ms,

maximum: see error reaction time

Error reaction time

≤ watchdog time

Cable length between sensor and terminal

unshielded max. 100 m (0.75 or 1 mm²) shielded max. 100 m (0.75 or 1 mm²)

Output current of the clock outputs

typically 10 mA, max. 15 mA

Input process image

6 bytes

Output process image

6 bytes

AKT2G-SDI-004 supply voltage (PELV)

24 VDC (–15% / +20%)

Signal voltage "0" inputs

-3 V to 5 V (EN 61131-2, type 3) see section Characteristic curve of the inputs

Signal voltage "1" inputs

11 V to 30 V (EN 61131-2, type 3) see section Characteristic curve of the inputs

Current consumption of the modular electronics at 24 V (without current consumption of sensors)

4 channels occupied: typically 12 mA

0 channels occupied: typically 1.4 mA

Current consumption via E-bus

4 channels occupied: approx. 200 mA

Power dissipation of the terminal

typically 1 W

Electrical isolation (between the channels)


Electrical isolation (between the channels and the E-bus)


Insulation voltage (between the channels and the E-bus, under common operating conditions)

insulation tested with 500 VDC

Dimensions (W x H x D)

12mm x 100mm x 68mm


approx. 50 g

Permissible ambient temperature (operation) up to SW 05

0 °C to +55 °C (see note in Installation position and minimum distances)

Permissible ambient temperature (operation) from SW 06 (week 02/2014)

-25°C to +55 °C (see note in Installation position and minimum distances)

Permissible ambient temperature (transport/storage)

-40°C to +70°C

Permissible air humidity

5% to 95%, non-condensing

Permissible air pressure (operation/storage/transport)

750 hPa to 1100 hPa

(this corresponds to a height of approx. -690 m to 2450 m over sea level assuming an international standard atmosphere)

Climate category according to EN 60721-3-3


(the deviation from 3K3 is possible only with optimal environmental conditions and also applies only to the technical data which are specified differently in this documentation)

Permissible level of contamination according to EN 60664-1

level of contamination 2

(comply with the section Safety I/O Maintenance)

Impermissible operating conditions

Safety terminals must not be used under the following operating conditions:

•   under the influence of ionizing radiation (that exceeds the level of the natural environmental radiation)

•   in corrosive environments

•   in an environment that leads to unacceptable soiling of the Bus Terminal

EMC immunity/emission

conforms to EN 61000-6-2 / EN 61000-6-4

Vibration/shock resistance

conforms to EN 60068-2-6 / EN 60068-2-27


15 g with pulse duration 11 ms in all three axes

Protection class


Permitted operating environment

In the control cabinet or terminal box, with minimum protection class IP54 according to IEC 60529

Permissible installation position

see section Installation position and minimum distances


CE, cULus

Media & Downloads

Title File Language Date Share URL
AKT2G I/O Manual EN English
Share URL /sites/default/files/public_downloads/AKT2G_IO.pdf
Title File Language Date Share URL
AKT2G-SDI-004-000 TUV Certification English
Share URL /sites/default/files/public_downloads/AKT2G-SDI-004%20TUV%20Certitication%20Rev.00.pdf
AKT2G-SDO-004-000 TUV Certification English
Share URL /sites/default/files/public_downloads/AKT2G-SDO-004%20TUV%20Certitication%20Rev.00.pdf
Kollmorgen EU Declaration of Conformity AKT2G (DE) English
Share URL /sites/default/files/public_downloads/ce_AKT2G%20IO_e.pdf

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