KROHNE OPTIWAVE 7300 IECEx - Manual (Page 14)

3
ELECTRICAL CONNECTIONS
14
OPTIWAVE 7300 C
www.krohne.com 10/2010 - 4000176502 - AD IECEX OPTIWAVE7300 R02 en
3.5.2 Maximum intrinsically-safe values for the electrical circuit
Level transmitter with the 4...20 mA output option (output terminal 1 or 2)
• U
i
≤30 V
• I
i
≤300 mA
• P
i
≤1 W
• C
i
=30 nF
• L
i
=0.2 mH
3.5.3 Supply voltage
Level transmitter with the 4...20 mA output option
3.5.4 Electrical schema
INFORMATION!
The optional second output is galvanically isolated from the main power supply, output 1 and
parts of the device that are grounded.
Current output terminal Minimum voltage at output
terminal [VDC]
Maximum voltage at output
terminal [VDC]
1 (U
S1
) 14 1 30 1
2 (U
S2
) 2 10 1 30 1
1 Minimum voltage at output terminal for a current output of 22 mA
2 Optional. Use a second power supply. This power supply energizes current output terminal 2 only.
Figure 3-2: Electrical schema for Ex i-approved equipment with the 4...20 mA output option
1 Intrinsically-safe power supply (use a second power supply for optional terminal 2 if the device has two 4...20 mA out-
puts)
2 Non-Ex zone
3 Ex zone
4 Resistor for HART
® communication