KROHNE ALTOSONIC V12 EN - Manual (Page 25)

ELECTRICAL CONNECTIONS
4
25
ALTOSONIC V12
www.krohne.com 04/2013 - 4002643502 - MA ALTOSONIC V12 R02 en
4.3 Digital I/O connections
• The digital outputs are passive open collector outputs, galvanically isolated from each other
and from the main circuit. To use these outputs an external voltage source and current
limiting resistors must be used. (NEC class 2 power supply (max. 100 VA, 24 VDC, IEC 61010-
1, clause 6.3.1 and 6.3.2)
• For frequencies above 100 Hz, use shielded cables in order to reduce radiation from
electrical interferences (EMC).
• Terminal A+ is not used.
WARNING!
1. In order to prevent unauthorized or inadvertent opening and removal of the covers, an inter-
locking device is provided for each cover. Before a cover can be rotated (counter clockwise) for
opening, release this interlocking device with a 2.5 mm Allen key.
2. The foot of the converter housing provide an earthing point, this must be connected to the near-
est safety earth conductor.
3. Only open the converter housing one minute after the power has been switched off and after it
has been verified that there is no risk due to the presence of potentially explosive gas.
Figure 4-2: Digital I/O as NPN transistor