Siemens SIMATIC C7-635, Manual

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Technical Specifications
A-18
C7-635 Control System
A5E00155581-04
Analog inputs
Number
Number of inputs
•
Current / voltage input
•
Resistance input
4 channels
1 channel
Cable length
•
Shielded Maximum 100 m (109 yd.)
Voltage, Currents, Potentials
Resistance input
•
No-load voltage 2.5 V, typically
•
Measured current 1.8 mA to 3.3 mA, typically
Galvanic isolation
•
Between channels and I/O
bus
Yes
•
Between channels No
Permissible potential difference
•
Between inputs and M
ANA
(V
CM
)
8.0 VDC
•
Between M
ANA
and M
internal
(V
ISO
)
75 VDC/60 VAC
Insulation tested at 500 VDC
Analog Value Generation
Measuring principle Momentary value encoding
(successive approximation)
Integration time/conversion time/tesolution (per channel)
•
Configurable Yes
•
Integration time in ms 2.5 / 16.6 / 20
•
Permissible input frequency Maximum 400 Hz
•
Resolution (including
overdrive)
11 bits + sign bit
•
Suppression of interference
frequency f1
400 / 60 / 50 Hz
Time constant of the input filter 0.38 ms
Basic execution time 1 ms