Operating Instruction

EDGE FCR 3 Operating Instruction
Page 52 of 64 Release Rev. C, 2019-09-10
© MYNXG Product GmbH, 2019. All rights reserved
6.7 HART and Current Loop Specifications
The HART interface is exposed at the terminal block with 8 positions to host a maximum of
four HART interfaces. The HART interfaces are integrated in line with the FieldCom-Group
specifications. MYNXG is certified member of the FieldCom-Group. The AD5755-1 provides
output voltages and currents with different ranges, which can be configured through the
software (see Table 14):
Table 14: Current Loop Specifications
Parameter
Min
Typ.
Max
Unit
Output Voltage Ranges
0
-
5
V
0
-
10
V
-10
-
+10
V
0
-
6
V
0
-
12
V
-6
-
+6
V
-12
-
+12
V
Output Current Ranges
0
-
24
mA
0
-
20
mA
4
-
20
mA
Resolution
16
-
-
Bits
In this case the 4-20 mA and the 0-12V ranges are used. The current loop sensors are
connected to a HART (AD5700). The used HART chip allows a signal generation, filtering,
detection, a frequency shift keyed modulation (FSK) and demodulation of the signal. Four
channels (A..D equal to 0..3) are available in the AD5755-1. Only one channel can be activated
each time. These 4 channels are connected to the HART through a multiplexer, whereby one
channel can be selected only.