Festo CPX-FVDA-P2 Original Instructions Manual page 19

General safety instructions
Term/abbreviation
Cross circuit
Cross-circuit monitor-
ing
Acknowledgment
Black channel
Safe state
Safety-related commu-
nication
Safety integrity
Safety integrity level
Safety circuit
Safety pilot circuit
Safety program
Festo — CPX-FVDA-P2 — 2018-10b
Meaning
Accidental bypasses in switches, e.g. between 0 V and FE. These can be
triggered, for example, by pinched cables and can cause impermissible
currents in circuits. If, for example, 0 V and FE are connected to each other
in the system power supply, a cross circuit between the 0 V current path
and FE downstream of the M-switch results in the switch being bypassed.
The switch is rendered ineffective. In a similar way, a cross circuit can also
result in the P-switch being bypassed.
Function that detects possible cross currents in the device's own circuits
and switches the device or the output channel into a safe state. This pre-
vents accidental switching of the load due to impermissible cross currents.
Signal or procedure for depassivation. By acknowledging, the user con-
firms that the module can be reintegrated, or the output channel can be
depassivated without any risk.
If the complete module has been passivated, acknowledgment is carried
out via regular reintegration (standard PROFIsafe process).
If an output channel has been passivated (channel-wise passivation),
acknowledgment takes place via an acknowledgement signal from the pro-
cess image 2.2.3 Bit pattern of the output and input data (F-user data).
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The transmission channels of PROFIBUS and PROFINET IO are not influ-
enced by PROFIsafe. They do not need to be considered in more detail with
regard to PROFIsafe and are therefore called black channels.
State in which the system is safe.
Exchange of safety-related messages between the F-Host and F-Device
(e.g. via PROFIsafe)
Effectiveness of safety functions in a safety-related system under require-
ment-based conditions.
Safety integrity level for safety-related systems in acc. with IEC 61508.
There are 4 levels (SIL 1 to SIL 4). SIL 1 is the lowest level and SIL 4 is the
highest level of safety integrity. The higher the level, the less probable it is
that the system will fail in a dangerous manner.
Output module CPX-FVDA-P2 with all the connected consumers. A safety
circuit is formed when the load to be operated safely is supplied from an
output (CH0, CH1, CH2) of the CPX-FVDA-P2. A switched-on (supplied) load
can either be safely switched off upon request (via PROFIsafe) or the mod-
ule automatically switches off the load safely if it detects a safety-related
error.
Safety circuit including safety-related control by the controller.
Safety-related user program in the F-Host
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