Stahl 8624-1, Operating Instructions Manual

Page: 41 / 60

167921 / 862460300010
S-BA-8624/1-01-en-30/07/2008
Function/troubleshooting
11
Control unit Ex p
8624/1
07188E02
Fig. 7-7: Circuit diagram, connection of an external signal lamp
X
If necessary, connect a signal station to the potential-free contact K1 (see fig. 7-7).
X
Close the enclosure cover of the control unit carefully.
X
Carefully screw down all the cable entries.
X
Ensure that unused cable entries are sealed with plugs certified to Directive 94/9/EC.
8 Function/troubleshooting
8.1 General functional description
07172E00
Fig. 8-1: General function
T1: After connecting the power and compressed air supply, the control unit starts a
self-test.
T2: Purging is finished.
The preset internal pressure of the enclosure is adjusted (2 mbar).
The devices in the Ex p enclosure are connected.
T3: Normal operation starts.
The internal pressure of the enclosure is regulated to the nominal value (2 mbar).
It is monitored in order not to fall below the MIN value (factory settings: 0.8 mbar)
or exceed the MAX value (factory settings: 15.0 mbar).
1 2
(+) 3
(-) 4 5
6 7
8
9 10
1 2
3
K1
L1 (+)
N (-)
PE
Ex p-release
external signal light
valve
0,0
10,0
8,0
6,0
4,0
2,0
T1 T2 T3