40 Function Description
WAGO I/O System 750 XTR
750-495/040-010 3-Phase POM 20KV 300A XTR
Manual
Version 1.0.0
The representation of the energy values can be scaled by a factor in the process
image (PI). This factor can be set by the user in accordance with the application
being used (WAGO-I/O-
CHECK
or register 35) and can be changed at any time.
The 2 examples below illustrate the information required for this:
Example 1:
- Meter for active energy import, L1 (UInt32 in the PA)
- Scaling (WAGO-I/O-
CHECK
, Register 35): 0 (1 mWh)
- Maximum value in the PI: 4,294,967,294
≙
~4,295 kWh
A counter overflow can occur for the counter shown in the PI even though the
internal meter has not yet reached the overflow threshold. This is signaled in
the PI by the flag “Range limiting for process value x.” The user must select the
scaling of the measured value in accordance with the application being used.
Example 2:
- Meter for total reactive energy (Int32 in the PI)
- Scaling (WAGO-I/O-
CHECK
, register 35): 7 (10 kVARh)
- Maximum value in the PI: +2,147,483,646
≙
~21,474,836,460 kVARh
Due to the scaling setting, an overflow of the internal meter can occur here, as
it can only count to a maximum of 9,999,999,999 kVARh. However, the value in
the PI could represent significantly higher energy values.
The values for the energy meters can be set via WAGO-I/O-
CHECK
. More
information on this is given in the section “Commissioning.”
The I/O module also allows you to set thresholds for energy measurement, i.e.,
energy is not metered until these start values settings are reached. This
threshold can be defined for each type of energy using WAGO-I/O-
CHECK
or
parameters 40, 41 and 42. More information on this is given in the section
“‘Module’ Tab.”
You can also define the storage interval using WAGO-I/O-
CHECK
or register 46
in which the energy meter values are saved internally. The valid range for this is
60 … 255 s. With a storage interval of 60 s, the lifetime of the internal meters is
around 190 years.
Determining the Frequency
The phase frequencies are calculated using zero crossing detection of the
sampled signals for each phase. The minimum and maximum frequencies are
determined over a configurable time period (WAGO-I/O-
CHECK
or parameters
37, 38 and 39).
