PROFIBUS DP mapping

PKW aperiodic service

The PKW service, consisting of PKE, R/W, R/W/N and PWE, enables aperiodic access to Altivar 312 parameters in read and write mode.

Output PKWs

PKE

Parameter logic address

R/W

0:No request

1:Read

2:Write

One-off read and write requests can be triggered continuously while R/W equals 1 or 2.

Note:

Values other than 0, 1 and 2 should not be used.

PWE

If write: Value to be written

Input PKWs

PKE

Copies the output PKE value

R/W/N

0:No request

1:Correct read operation

2:Correct write operation

7:Read or write error

PWE

If correct read operation: Parameter value. This can be limited by the drive if the maximum value is exceeded by the write operation.

If correct write operation: Value of the write PWE

If there is an error:

0:Incorrect address

1:Write operation refused

Note:

The parameters in the output PZDs should not be changed by the PKW service.

Parameters linked to output PZDs should not be changed by the PKW service.

Example: The speed target and the frequency target.

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S1A10386 10/2009

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Schneider Electric 312 manual PKW aperiodic service, Output PKWs, Input PKWs