Siemens SIMATIC S7-1500 Manual page 71

Configuring/address space
4.3 Manual operation (without technology object)
Feedback bit/value Explanations
LD_ERROR This bit indicates that an error occurred (latching) during loading via the control interface. The load-
ed values were not applied. When using an incremental or pulse encoder, one of the following con-
ditions is not fulfilled:
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•
•
When using an SSI absolute encoder, one of the following conditions is not fulfilled:
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•
The bit is reset once you have acknowledged the error with RES_ERROR .
LD_STS_SLOT_0 This bit indicates by a status change (toggling) that the load request for SLOT_0 (LD_SLOT_0) was
detected and performed.
LD_STS_SLOT_1 This bit indicates by a status change (toggling) that the load request for SLOT_1 (LD_SLOT_1) was
detected and performed.
MEASURED_VALUE This value indicates the current measured value with data type REAL or the complete SSI frame
with data type DWORD:
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•
•
•
The measured values are returned as a signed value. The sign indicates whether the counter value
or position value went up or down in the relevant time interval.
The update time is asynchronous to the opening of the internal gate, i.e. the update time is not
started when the gate opens. After the internal gate closes, the last calculated measured value
continues to be returned.
POWER_ERROR This bit indicates that supply voltage L+ is not present or is too low or the front connector is not
inserted. If you have enabled the diagnostic interrupts (Page 76), the diagnostic interrupt "Load
voltage missing" is triggered at a supply voltage error.
When supply voltage L+ is available at a sufficient level once again, POWER_ERROR is automati-
cally set to 0.
RES_EVENT_ACK This bit indicates that the reset of event bit EVENT_SYNC, EVENT_CMP0, EVENT_CMP1,
EVENT_OFLW, EVENT_UFLW, EVENT_ZERO is active.
Reserved Reserved bits are set to 0.
STS_CNT This bit indicates that at least one count pulse or a position value change has occurred in the last
ca. 0.5 s.
STS_DI0 This bit indicates the status of digital input DI0.
STS_DI1 This bit indicates the status of digital input DI1.
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Low counting limit <= counter value <= high counting limit
Low counting limit <= start value <= high counting limit
Low counting limit <= comparison value 0/1 <= high counting limit
0 <= position value <= maximum position value
0 <= comparison value 0/1 <= maximum position value
Frequency: The mean frequency is calculated from the time profile of the count pulses or posi-
tion value changes in one measurement interval and returned as a floating-point number in the
unit of hertz.
Period: The mean period is calculated from the time profile of the count pulses or position value
changes in one measurement interval and returned as a floating-point number in the unit of
seconds.
Velocity: The mean velocity is calculated from the time profile of the count pulses or position
value changes in one measurement interval and returned as a floating-point number in the con-
figured unit.
Complete SSI frame: Instead of a measured quantity, the least significant 32 bits of the unpro-
cessed current SSI frame are returned. This provides you with encoder-specific additional bits,
such as error bits, in addition to the position value. If the SSI frame is shorter than 32 bits, the
complete SSI frame is returned right-aligned and the top unused bits are returned with "0" in the
feedback interface.
Technology module TM PosInput 2 (6ES7551-1AB00-0AB0)
Manual, 06/2018, A5E03982218-AB