Safety
10
2.6 Safety circuit of the
The safety circuit ensures that the Autoloader can only be commissioned under certain
conditions.
The safety circuit checks the following conditions:
•
Pneumatic pressure is present
•
Furnace cover has been installed and closed
•
Crucible bin is present
If one of these conditions is not met, the power supply to the main board and to the valves of
the Autoloader will be interrupted. The gripper fingers remain closed. Crucibles are furthermore
held for at least 5 minutes in the event of a fault. The following diagram shows the safety circuit
procedure:
Fig. 1: Flow diagram of the safety circuit
Pneumatic pressure ok?
Top/bottom cover
assembled?
Autoloader switched on?
Furnace cover
closed?
Crucible bin in place and
not full?
Relay:
Power supply to the main board is
established.
Power supply to the pneumatic
valves is established.
Gripper fingers:
Controlled by the software.
Relay:
Power supply to the main board is
interrupted.
Power supply to the pneumatic
valves is interrupted.
Gripper fingers:
Closed by the safety circuit.
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
