Siemens SIPART DR22 Manual page 17

Manual
The signal lines are connected by a plug terminal block with screw terminals. When using ther-
mocouples with internal reference junction terminal, this terminal block must be replaced by the
terminal 6DR2805-8A. With the measuring for TC, internal connector 6DR2805-8J in place of
the terminal block, the measuring range of the direct input (0/20 to 100 mV) can be extended to
0/2 up to 10 V or 0/4 up to 20 mA.
The UNI module operates with an AD converter with 18 bit resolution. The measuring inputs
and ground of the standard controller are electrically isolated with a permissible common mode
voltage of 50 V UC.
6DR2805-8A reference junction terminal
D Terminal with internal reference junction terminal for thermocouples
This terminal is used in connection with the UNI module for temperature measuring with ther-
mocouples at an internal reference junction terminal. It consists of a temperature sensor which
is pre-
assembled on a terminal block and plated to avoid mechanical damage.
6DR2805-8J measuring for TC, internal connector
D measuring for TC, internal connector for current 0/4 to 20 mA or voltage 0/2 to 10 V
The measuring for TC, internal connector is used in connection with the UNI module to
measure current orvoltage. The input variable is reduced to 0/20 to 100 mV by a voltage divider
or shunt resistors in the measuring for TC, internal connector.
Wiper resistors with 250 Ω or 50 Ω are available optionally at 2 different terminals for 0/4 to
20 mA signals.
The electrical isolation of the UNI module is retained even when the measuring for TC, internal
connector is used.
6DR2801-8D Module with 2 BA relays
D Digital output module with 2 relay contacts
To convert 2 digital outputs to relay contacts up to 35 V UC.
This module is equipped with 2 relays whose switching contacts have potential free outputs.
The RC combinations of the spark quenching elements are respectively parallel to the rest and
working contacts.
In AC consumers with low power the current flowing through the capacitor of the spark
quenching element when the contact is open may interfere (e.g. the hold current of some
switching elements is not exceeded). In this case the capacitors (1 μF) must be removed and
replaced with low capacitance capacitors.
The 68 V suppressor diodes parallel to the capacitors act additionally to reduce the induced
voltage.
SIPART DR22 6DR2210
C79000-G7476-C154-03
1 Technical Description
1.4 Function principle
1.4.2 Description of the option modules
15