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CR720S CR721S
36
ifm electronic gmbh ● Friedrichstraße 1 ● 45128 Essen We reserve the right to make technical alterations without prior notice!
26/11/2020
CR721S / page 6
CR721S (HW version: V1.0.5.x)
ST A and ST B / input characteristics
Control systems
ST A:
IN0000...0003
IN0500...0503
ST B:
IN1000...1003
IN1500...1503
Resolution
12 bits
Digital inputs, frequency measure-
ment
(IN FREQUENCY-B)
Frequency input (FRQ
L/H
)
Input resistance
10 kΩ
Input frequency
Mode
min.
(Hz)
max.
(kHz)
IN_PERIOD_RATIO_CSx
0.01
5.0
IN_PERIOD_RATIO_US_CSx
0.1
5.0
IN_FREQUENCY_CSx
0.5
30.0
IN_COUNT_CSx
0.0
30.0
IN_INC_ENCODER_CSx
0.0625 5.0
IN_PHASE_CSx
0.0625 5.0
Switch-on level
> 0.7 VBB
30
Switch-off level
< 0.3 VBB
30
Accuracy
± 10 µs
Voltage input 0...10 V (A)
Input resistance
67.6 kΩ
Range diagnostics min./max.
0 V / 10 V (default)
Accuracy
± 1 % FS
Digital input (B
L/H
)
(default: B
L
)
Input resistance
10 kΩ
Input frequency
< 330 Hz
Switch-on level
> 0.7 VBB
30
Switch-off level
< 0.3 VBB
30
Accuracy B
L
/ B
H
± 1 % FS / ± 3 % FS
Range diagnostics
configurable minimum and maximum values
for the measuring range to detect short circuit
to VBB and short circuit to GND / wire break
Range diagnostics min./max.
1 V / 0.95 VBB
30
(default)
ST A:
IN0400...0401
IN0900...0901
Resolution
12 bits
Input frequency
< 330 Hz
Range diagnostics
configurable minimum and maximum values
for the measuring range to detect short circuit
to VBB and short circuit to GND / wire break
Digital/ resistor inputs
(IN RESISTOR-A)
Digital input (B
L
)
(default)
Input resistance
3.2 kΩ
Switch-on level
> 0.7 VBB
30
Switch-off level
< 0.3 VBB
30
Accuracy B
L
± 1 % FS
Range diagnostics min./max.
1 V / 0.95 VBB
30
(default)