4-channel digital output terminal, TwinSAFE, 24 V DC KL2904
Diagnostic 3, 4 
Diagnostic 1, 2 
Output 3, 4 
Output 1, 2 
Power contact
+24 V
Power contact 0 V
Output 1, 2
Output 3, 4
Top view 
Contact assembly 

KL2904 | 4-channel digital output terminal, TwinSAFE, 24 V DC

The KL2904 safety Bus Terminal is a digital output terminal with four channels. It switches 24 V DC actuators with up to 0.5 A current per channel. The KL2904 meets the requirements of DIN EN ISO 13849-1:2008 (Cat 4, PL e) and IEC 61508:2010 (SIL 3). If the Bus Terminal detects a fault, it switches off automatically (fail stop).

Technical data KL2904
Connection technology 2-wire
Safety standard DIN EN ISO 13849-1:2008 (Cat 4, PL e) and IEC 61508:2010 (SIL 3)
Number of outputs 4
Protocol TwinSAFE/Safety over EtherCAT
Status display 8 LEDs: 1 per output, 4 diagnostic
Current consumpt. K-bus 250 mA
Fault response time ≤ watchdog time (parameterisable)
Bit width in the process image 6 byte input/6 byte output
Supply voltage 24 V DC (-15 %/+20 %)
Output current 0.5 A max./20 mA min. (per channel)
Special features 4 safe outputs
Weight approx. 100 g
Operating/storage temperature 0…+55 °C/-25…+70 °C
Permitted degree of contamination 2
Climate class EN 60721-3-3 3K3
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
Installation position horizontal
Protection class IP 20
Approvals CE, UL, Ex, TÜV SÜD