Siemens 6DR2410, Manual

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Manual 1 Technical Description
1.4 Function Principle
1.4.2 Description of the Option Module
SIPART DR24 6DR2410
C79000-G7476-C153-03
13
6DR2800-8A 3 AE module
D
Inputs for current and voltage
To expand the analog inputs.
Description of the module and technical data, see chapter 1.6.2, page 95 (Inputs standard con-
troller).
6DR2800-8J I/U module
D
Input variables current 0/4 to 20 mA or voltage 0/0.2 to 1 V or 0/2 to 10 V
The input amplifier of the module is designed as a differentiating amplifier with jumperable gain
for 0 to 1 V or 0 to 10 V input signal. For current input signals the 49.9 W 0.1 % impedance is
switched on by plug--in bridges on the module. The start value 0 mA and 4 mA or 0 V or 0.2 V
(2 V) is defined by configuration in the standard controller. The differentiating amplifier is de-
signed for common mode voltages up to 10 V and has a high common mode suppression.
As a result it is possible to connect the current inputs in series as for electrical isolation when
they have common ground. At voltage inputs this circuit technique makes it possible to sup-
press the voltage dips on the ground rail by two--pole wiring on non floating voltage supplies.
We refer to an electronic potential isolation.
6DR2800-8R R module
D
Input for resistance or current transmitter
Potentiometers with rated values of 80
Ω
to 1200
Ω
can be connected as resistance
transmitters. A constant current of Is = 5 mA is fed to the potentiometer wiper. The wiper
resistance is therefore not included in the measurement. Resistances are switched parallel to
the potentiometer by a slide switch on the module and a rough range selection made. Range
start and end are set with the two adjusting pots on the back of the module.
This fine adjustment can be made via the displays on the front module (with the appropriate
configuring). For adjustment with a remote measuring device, the analog output can be as-
signed to the appropriate input.
The external wiring must be changed for resistance transmitters which cannot withstand the
5 mA wiper current or which have a rated resistance > 1 k
Ω
. The constant current is then not
fed through the wiper but through the whole resistance network of the potentiometer. A voltage
divider measurement is now made through the wiper. Coarse adjustment is made by a remote
parallel resistor to the resistance transmitter.
This module can also be used as a current input with adjustable range start and end. The load
is 49.9
Ω
and is referred to ground.