6
Assembly Instructions
enCore FC
Operating Instructions
Page 81 of 120
6.4.17 Gas Meter (Turbine): Encoder Index, 2 LF/HF Sensors
(EEx i) via ExMFE5 Boards
Hazardous Area
Safe Area
enCore device
Turbine:
encoder and
2 LF/HF sensors
Z1+
Z1−
SH
Z2+
Z2−
Z3+
Z3−
12 345 67,8
ExMFE5 board
Fig. 6-22: Interface for turbine meter
encoder index, 2 LF/HF sensors (EEx i) via ExMFE5
Characteristics ExMFE5:
•
three intrinsically safe, galvanically isolated input safe circuits of the
category [Ex ib Gb] II C for HF- or LF pulse sensor according to
NAMUR;
active isolated pulse amplifier integrated in the inputs as
“associated electrical equipment” according to EN50020
•
Alternatively, one encoder index can be connected with NAMUR
interface on channel 1.
•
max. input frequency depending on the operating mode:
− LF:
2 Hz,
min. pulse length 200 ms
− HF:
5 kHz
