KROHNE VARIFLUX IFS 6000 F-EEx EN - Manual (Page 7)

ALTOFLUX IFS 4000F-EEx, PROFIFLUX IFS 5000F-EEx, VARIFLUX IFS 6000F-EEx 7
1.2.1 Mechanical construction
The IFS 5000 F-EEx primary head is the measuring unit of the flowmetering system (see block
diagram in section 1.4). It contains two field coils and two electrodes in type of protection intrinsic
safety category "ib" according to EN 50020. The type of protection of the field coils is Encapsulation
"m" according to EN 50028 and Increased Safety "e" according to EN 50019.
The electrode circuits are wired by separate shielded cables and marked by the color of the outer
insulation sheath of the cable (white and purple). The intrinsical safe "EEx ib" electrode circuits inside
the IFS 5000 F-EEx primary head have the following maximum values (entity parameters):
Maximum input voltage
U
max
= 20 V
Maximum input current I
max
= 170 mA
Maximum internal capacitance C
i
= 0
Maximum internal inductance L
i
= 0
The two field coils inside the primary head are connected in series and have a maximum resistance
of approximately 60
Ω per coil with a wire diameter of at least 0.25 mm and insulation class H (T
max
≥
180°C) according to IEC 85. The field coils are supplied with a square-wave signal with a voltage of ±
40 V and a nominal current of 125 mA. The coil circuit is protected by two 160 mA series fuses,
which are installed inside the associated signal converter unit (e.g. IFC 090 F/…-EEx).
1.2.2 Data plates of PROFIFLUX IFS 5000 F-EEx
Data plate 1 Data plate 2