Analog Output Modules - Siemens SIMATIC S5-100U System Manual

S5-100U
11.5

Analog Output Modules

Analog output modules convert the bit patterns that are output by the CPU into analog output
voltages or currents.
11.5.1 Connection of Loads to Analog Output Modules
No adjustments are necessary if you want to connect loads to the analog outputs.
Check the following items before connecting loads:
• The load voltage 24 V DC must be connected to terminals 1 and 2.
• The maximum permissible potential difference between the outputs is 60 V AC.
• Unused outputs must be left open-circuited.
Figure 11-9 shows how to connect loads to the voltage outputs of the following modules:
• 470-8MA12 (2x±10 V)
• 470-8MD12 (2x+1 to 5 V)
The sensor lines (S+ and S-) must be directly connected to the load, so that the voltage is
measured and regulated directly at the load. In this manner, voltage drops of up to 3 V per line can
be compensated for.
The sensor lines can be left out if the resistances of the QV and M lines are negligible compared to
the load resistance. In such a case, connect terminal S+to terminal QV, and terminal S- to M
1
L+ M
24 V DC
(4/8) (3/7)
QV S+
R
L
Figure 11-9. Load Connection via a Four-Wire Circuit (6ES5 470-8MA12 or 6ES5 470-8MD12)
EWA 4NEB 812 6120-02b
S+ S- S+
3 5 7
QV
M QV
ANA
2 4 6 8
(5/9) (6/10) Terminal assignment
S- M Terminals
ANA
Analog Value Processing
S-
9
Key:
M
ANA
QV: Analog output "Voltage"
S±: Sensor line
M
: Chassis ground terminal
10
ANA
of the analog unit
R : Load resistor
L
.
ANA
11-19