Samson 3730-4 - CHECKBACK - Device Status

14.2.3 Integration for PCS7 control system
The following steps must be observed on integrating the positioner into a Simatic S7 control
system to ensure that the positioner functions properly:
1. The module in Slot 1 can be read out over the function component SFC 14 “DPRD_DAT“
and, for example, assigned to a data module.
2. Existing modules in Slot 2 and/or Slot 3 need to be allocated over the MOVE command
as the use of SFC 14 is not permissible in this case.
Note: Data consistency is first provided from a data length of 3 bytes or 5 bytes.
Use the MOVE command for data types BYTE, WORD and DWORD.
If the SFC 14 is to be used over several slots, do not forget that the data length is always to
be regarded for each slot separately!
14.2.4 General instructions to start up the positioner
The positioner remains in the fail-safe position until it receives a valid setpoint from the pro-
cess control system (status < 0x80). S blinks on the positioner display to indicate that the
positioner is in the fail-safe position (see page 55). First when a valid set point (status
≥
0x80) is set, the positioner leaves the fail-safe position and follows the reference variable.
14.3 CHECKBACK – Device status
Each bit can be masked individually for cyclic communication per class 2 master. This allows
a targeted selection to be made from the existing alarms.
Byte Bit Name Description
0 0 CB_FAIL_SAFE Fail-safe position: The fail-safe position has been trig
-
gered. This may have been caused by the local operation,
activation of the SET_ FAIL_SAFE_POS option or due to a
communication failure.
R
1 CB_REQ_LOC_OP Request for local operation: This is set when the initializa
-
tion key of the local operation is activated.
A
2 CB_LOCAL_OP Local operation:
•
The device has been set by the local operation into the
MAN or SAFE mode.
•
The device is in the self-testing mode (initialization, zero
point calibration or diagnostic function active). In this
case, the CB_SELFTEST bit is also set.
R
94 EB 8384-4 EN
PROFIBUS-PA communication
INIT