VEGA VEGASON 51K…53K - Manual (Page 13)

VEGASON 51K … 53K 13
- +
4 … 20 mA
2
2
2
4
Measuring system with VEGASON 51K … 53K vi a separator (Smart-Trans-
mitter) on passive DCS
• Two-wire technology (loop powered), intrinsically ia-supply via the signal line from the sepa-
rator for operation of the sensor in Ex-Zone 1
• Output signal sensor 4 … 20 mA passive
Output signal separator 4 … 20 mA active
• Optional external indicating instrument with analogue and digital indication (can be mounted
up to 25 m away from the sensor)
• Adjustment with PC, HART ® -handheld or adjustment module MINICOM (can be plugged in
the sensor or in the external indicating instrument VEGADIS 50)
Types and versions
(active) 2)
VEGA-
CONNECT 2
Separator (e.g. VEGATRENN 149 Ex see
"3.2 Approvals“)
VEGADIS 50
1 )
DCS (passive) 3)
Ex-area Not Ex-area
1) If the resistors of the processing systems
connected to the 4 … 20 mA-signal output are less
than 200
Ω
, a resistor of 250
Ω
to 350
Ω
must be
connected to the connection line during adjust-
ment.
The digital adjustment signal would be extremely
damped or short-circuited via too small input
resistors of the connected processing system
which means that the digital communication with
the PC could no longer be ensured.
2) 4 … 20 mA active means that the separator
delivers level dependent a current of 4 … 20 mA.
The separator therefore reacts electrically against
the DCS like a current source.
3) 4 … 20 mA passive means that the sensor takes,
a current of 4 … 20 mA, depending on the level.
The sensor therefore reacts electrically like a
resistor (consumer) on the DCS.
HART ® -handheld