Endress+Hauser Levelflex FMP56 Operating Instructions Manual page 40

Electrical connection
40
CAUTION
L
To ensure electrical safety:
‣
Do not disconnect the protective ground connection.
‣
Disconnect the device from the supply voltage before disconnecting the protective
ground.
Connect protective ground to the inner ground terminal (3) before connecting the
power supply. If necessary, connect the potential matching line to the outer ground
terminal.
In order to ensure electromagnetic compatibility (EMC): do not ground the device
exclusively via the protective ground conductor of the supply cable. Instead, the
functional grounding must also be connected to the process connection (flange or
threaded connection) or to the external ground terminal.
An easily accessible power switch must be installed in the proximity of the device. The
switch must be marked as a disconnector for the device (61010IEC/).
Function diagram 4-wire: 4 to 20 mA HART (90 to 253 V
3
2
1
 24 Function diagram 4-wire: 4 to 20 mA HART (90 to 253 V
1 Evaluation unit, e.g. PLC
2 Resistor for HART communication (≥ 250 Ω); observe maximum load
3 Connection for Commubox FXA195 or FieldXpert (via VIATOR Bluetooth modem)
4 Analog display unit; observe maximum load
5 Cable screen; observe cable specification
6 Device
7 Supply voltage; observe terminal voltage, observe cable specification
7.1.2 Cable specification
• Devices without integrated overvoltage protection
Pluggable spring-force terminals for wire cross-sections 0.5 to 2.5 mm
• Devices with integrated overvoltage protection
Screw terminals for wire cross-sections 0.2 to 2.5 mm
• For ambient temperature T
HART
• A normal device cable suffices if only the analog signal is used.
• A shielded cable is recommended if using the HART protocol. Observe grounding concept
of the plant.
• For 4-wire devices: Standard device cable is sufficient for the power line.
7.1.3 Device plug
In the case of the device versions with a plug, the housing does not need to be opened
to connect the signal cable.
+
-
L
N
AC
≥60 °C (140 °F): use cable for temperature T
U
Levelflex FMP56, FMP57 HART
)
AC
4
5
6
3
I
4
Y
1
2
7
)
2 (20 to 14 AWG)
2
(24 to 14 AWG)
+20 K.
U
Endress+Hauser
A0036527