Pn Plus Terminal Box - Siemens SINUMERIK 840D sl Equipment Manual

Connecting
7.2 Terminal Box PN
7.2.2

PN Plus terminal box

The PN Plus terminal box differs from a PN Basic terminal box in that it has four relays mounted
on the board.
①
②
Figure 7-3
Switching states of the emergency stop circuit
HT 8
Connected
Connected
Not connected
Danger of death resulting from the inadvertent disconnection of the HT 8
If you disconnect the HT 8 from the PN Plus terminal box, the emergency stop circuit is closed,
thereby clearing the stop state of the system to be monitored. This occurs irrespective of
whether the emergency stop button has been pressed on the HT 8.
102
Board
Relays
Inner view of the PN Plus terminal box
Emergency
Stop button
Not pressed
Pressed
WARNING
Switching status, emergency stop circuit
Emergency Stop circuit in the terminal box remains closed.
The emergency stop circuit in the terminal box is open.
The system to be monitored is stopped.
- Emergency Stop circuit in the terminal box remains closed.
Handheld Terminal HT 8
Equipment Manual, 02/2024, A5E52918633B AA