
Functions
Leuze electronic
MSI-TRMB
16
Figure 4.6: Start/restart interlock and contactor monitoring (EDM)
Figure 4.7: Automatic start with EDM
A feedback contact of an external contact extension (K
ext
) can be connected in series with the start button.
Changing between the two start configurations is not allowed during operation. If a change is detected, the
device enters the error state and indicates this via the LEDs (see chapter 3.3 "Error display"). The specific
wiring of the external relays is shown in the application examples (see figure 7.1 – see figure 7.11). With
a monitored start, the device reacts to the falling edge of the start button; with a non-monitored start, it
reacts to the rising edge or the static signal.
4.8
Error state FAIL SAFE
If the device is in an error state (FAIL SAFE), this is indicated by the LEDs (see chapter 3.3 "Error display").
In the error state, the OSSD safety switching outputs (relay outputs) and control outputs S11 and S21 are
switched off. The device no longer reacts to input actuation, e.g. pressing of the start button.
The error state can be reset by means of a software reset (see chapter 4.8.1 "Software reset") or by briefly
switching off the voltage supply at A1, e.g. using a reset button connected in series to the supply voltage
at A1.
4.8.1 Software reset
If the safety relay indicates a fault, it can be reset as follows:
• With monitored start: press the start button for at least 4 s.
• Between S35 and S36: press a button connected for the reset, for at least 4 s.
NOTICE
Operation of the device in the E-Stop application with automatic start (without restart interlock) is not
allowed.
NOTICE
With monitored start, K
ext.
must be connected between the start button and S35.
Start
S36
S35
K
ext
Start
S33
S34
K
ext