4 adjustment with hart® handheld, 4 adjustment with hart, Handheld – VEGA Capacitive electrodes EL 4 … 20 mA - Compact User Manual

Page 31: Multidrop mode, Burst mode

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Capacitive electrodes EL 4 … 20 mA - Compact

31

22652-EN-020809

Connection to a VEGA signal conditioning
instrument

(fig. 3 on the next page)
If you operate a HART

®

capable sensor on a

VEGA signal conditioning instrument, you
have to a connect a resistance (acc. to the
following table) to the sensor connection on
the signal conditioning instrument during the
HART

®

adjustment.

VEGA signal conditioning instr.

Rx

VEGAMET 513, 514, 515, 602
VEGATRENN 544
VEGATOR 521…527

50 … 100

Ohm

VEGAMET 614

no additional

VEGADIS 371

resistance
necessary

VEGAMET 601

200 … 250 Ohm

VEGASEL 643

150 … 200 Ohm

VEGAMET 513 S4, 514 S4
515 S4

100 … 150 Ohm

4.4 Adjustment with HART

®

handheld

The capacitive electrodes EL with oscillator
CAP E32 H Ex are HART

®

protocol capable

and can be adjusted with a HART

®

handheld.

All relevant sensor functions can be executed
with the HART

®

standard menus. A manufac-

turer-specific DDD (Data-Device-Description)
is not necessary.
Connect the HART

®

handheld to the sensor

signal cable after you have connected the
sensor to power supply.

Multidrop mode

The multidrop mode can be selected with the
HART

®

handheld.

With this mode, several HART

®

sensors can

be connected to a single two-wire cable.
Beside the 4 … 20 mA signal, the sensor also
delivers a digital (HART

®

) level signal.

• If you enter address 0 (factory setting), the

sensor consumes a level-dependent
4 … 20 mA current and delivers a digital
(HART

®

) level signal. It is also possible to

connect e.g. an indicating instrument
(4 … 20 mA) to this cable.

• If you enter an address between 1 and 15,

the sensor consumes a permanent 4 mA
current and delivers a digital (HART

®

) level

signal.

Burst mode

Normally the sensor signals the measured
values to the processing unit only on request.
If you switch on the burst mode, the sensor
signals the measured value without being
requested.

4

3

2

1

+ - + -

mA

250 Ohm

HART

®

handheld

Setup

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