Current Measurement/Control - Siemens ET 200SP Manual

Configuring/address space
4.2 Pulse width modulation PWM mode
4.2.1.7

Current measurement/control

Current measurement
The technology module measures the load current at the digital output. The measured value
of the current is returned as an S7 analog value in the MEASURED_CURRENT value in the
feedback interface (Page 58).
A valid measured value is available when the STS_ENABLE feedback bit is set after the first
period duration of the output sequence. The returned measured value is an average of the
measured values that were acquired over a time period of at least one period duration. If a
valid measured value is not available, the value 32767
When dithering is active, the average is for the time period of an entire dithering period
duration.
Note
In order to use the current measurement, the high-speed output must be deactivated.
Measuring range and accuracy
The measuring range and accuracy are dependent on the channel configuration:
Two-channel opera-
tion
One-channel opera-
tion
(parallel connection)
May only be exceeded for a short time.
1
When this current value is exceeded, the ERR_DQA feedback bit will be set.
2
With constant period duration in the respective measuring period.
3
44
Measured value Maximum measured
27648
D
2 A
1
4 A
1
Technology Module TM Pulse 2x24V (6ES7138‑6DB00‑0BB1)
is returned.
D
value
Period duration >
32511
D 333 μs
2.37 A ±40 mA
2
4.74 A ±80 mA
2
Manual, 05/2019, A5E35061186-AB
Accuracy
3
Period duration <
333 μs
-40 mA ...
+100 mA
-80 mA ...
+200 mA