Advantages of AS-i
System overview
AS-i safety at work

AS-i functional safety

Safety at Work (SAW) has been available since 2000 as the first approved safety networking technology. SAW is an approved safety network that incorporates the required international safety approvals for functional safety. The system is certified by TUV, a Nationally Recognized Testing Laboratory that is recognized by OSHA.

Safety at Work wiring benefits

One cable from the main control cabinet for safety wiring
Feedback wiring is eliminated
Eliminates the need for additional PLC cards
M12 patch cables used for connecting safety devices to safety input modules

Operating principle

Each fail-safe AS-i slave has a unique code sequence that is 8 x 4 bits. While the contacts are in the closed position, a 32 bit number is transmitted over the AS-i cable 4 bits at a time. After eight scans, the pattern repeats. The bit pattern is referred to as a "Code Table".

The fail-safe AS-i slave responds to each cyclic data call of the AS-i master with one of the following:

the consecutive part of its code sequence if its two channels are active (ex. - e-stop unlocked)
"00xx" or with "xx00" if one of its two channels is inactive
"0000" if both channels are inactive.

The AS-i safety monitor only listens to the communication between the AS-i master and fail-save AS-i slave. The safety monitor also knows the code sequence of each configured safe AS-i slave because it is taught during set-up. The safety monitor safely switches off its output if the c ode sequence is received incompletely or not at all.

Select an AS-i safety monitor

	IP rating	Certifications	Features
AS-i safety monitor	IP 20	SIL 3 SILcl 3 PL e Cat. 4	Integrated safety monitor Safety relay with parameter setting via safety-certified ASiMon software Monitorin up to 31 fail-safe AS-i slaves Local fail-safe I/Os Chip card for storing the configuration

Select fail-safe AS-i modules

Part numbers	Description	IP rating	Certifications	Inputs	Outputs
AC009S / AC030S	Control cabinet module	IP 20	SIL 3 SILcl 3 PL e Cat. 4	2 SI (mechanical contacts (NC)) 4 I (non-safe) Sensor supply: AS-i	2 LED 2 relays (non-safe) 1 SQ relay
AC50xS	ClassicLine with quick mounting technology	IP 67	SIL3 SILcl 3, SILcl 2 PL e Cat. 4, PL d Cat. 3	2 SI (mechanical contacts (NC), OSSD, electronic contacts) Sensor supply: AS-i, AUX	2 LED 2 semiconductor outputs (non-safe)
AC01xS	E-stop	IP 67	SIL 3 SILcl 3 PL e Cat. 4	2 SI (2-channel mechanical contacts (NC)) 2 I Sensor supply: AS-i	1 LED 3 LED
PCB solutions	With the help of AS-i PCBs mechanical switches can be integrated into AS-i networks	Depends on housing	SIL 3 PL e Cat. 4	2 SI (2-channel mechanical contacts (NC)) Sensor supply: AS-i	1 LED
AC90xS	Safety switch with guard locking	IP 67	PL d	2 SI (2-channel mechanical contacts (NC)) Sensor supply: AS-i	2 LED 1 lock