Jetter JM-204-480, User Manual, Page: 102 / 126

13 Safe Standstill (Option)
102 Jetter AG
13.5.4 Application 3
Fig.: 28: Application 3
The safety device(s) transmit(s) a +24 V signal for activating the digital servo
amplifier to the input Enable1 and Enable2 individually. There are alternating
interruptions of 1 ms max. with each signal, which serve checking the signals for
shorts between contacts, short circuits or interference voltages (OSSD-signals). This
interruption of 1 ms max. will not lead to deactivating the servo amplifier, though. At
calling up the safety function, the signals are omitted. This blocks the servo controller
from being activated. In case of an error, it is sufficient that at least one of those two
signals is omitted, in order to switch off the motor safely (dual-channel switch-off).
Deactivating the inputs leads to immediate switching off the motor (Stop Category 0).
Possible errors (such as short circuits, shorts between contacts, or a quadrature-axis
component of voltage) can be recognized and safely controlled.
Following this example, "Safe Standstill" (according to EN 954-1 Category 3) with
Stop Category 0 (according to EN 60204) can be set up, if all safety devices involved
also meet the requirements of Category 3.
If the application allows for regular tests of the switch-off function, even the
requirements of category 4 to EN 954-1 can be met by means of connections to fig.
28, if all safety measures taken also meet the requirements of category 4. The time
intervals in between the test runs depend on the quality of the external controlling
devices, yet they should exceed 24 hours.
E2
COM
E1
X73
Safety
device
JetMove (D)2xx
Safety
device