Leuze electronic
MSI 420.TMC-03
6
3.3
Muting phases
Phase 1 - Preparing muting
First, the two control signal inputs on the MSI 400 must be activated, i.e. a HIGH signal must be present
at each input. When doing so, it is essential to ensure that the control signals originate from different signal
sources. Typically, the Control 1 signal is generated by the PLC whereas the Control 2 signal comes from
the conveyor belt (e.g. motor contactor).
The sequence in which the control signals are applied is irrelevant for operation of the MSI 400. The time
period between application of Control 1 and Control 2 can be between 0 ms and any length of time. The
control signals must remain active (HIGH level) throughout the entire muting process.
To test the muting sensors, the MSI 400 outputs a test pulse at the Start 1 OUT / Start 2 OUT outputs.
Each time an edge change is requested, a maximum reaction time (tR) of 240 ms is available for the
sensors. This means that at the Start 1 IN / Start 2 IN inputs the MSI 400 expects them to follow the
predefined signal change within the predefined time. The muting function is ready as soon as testing of
Start 1 and Start 2 has been successfully completed.
If tR is exceeded, muting is not initiated and an error message is output (see chapter 5 "Diagnostics
Start 1
Start 1 IN, input
Muting sensor 1, receiver
A test cycle initiated by the
MSI 400 checks whether
an edge change pre
-
defined at "Start 1 OUT/
Start 2 OUT" is registered
by the muting sensor and
returned to the MSI 400 via
"Start 1 IN/Start 2 IN".
Start 1 OUT, output
Muting sensor 1, transmit
-
ter
Start 2
Start 2 IN, input
Muting sensor 2, receiver
Start 2 OUT, output
Muting sensor 2, transmit
-
ter
SLS receiver
Input
Protective sensor
Receiver of the protective
sensor
SLS transmitter
Test output
Protective sensor
Transmitter of the protec
-
tive sensor
Start/activation input Input
External sensor or PLC
Depending on the operat
-
ing mode, this input func
-
tions as the start input or
activation input
Signals at MSI 400
Source
Description
Figure 3.1: Phase 1 - Muting preparation is activated by applying the control signals. The pallet is still
completely inside the danger zone.
Danger zone
Protective sensor
Start 1
Start 2
