Allen-Bradley PowerFlex 755TL User Manual

102 Rockwell Automation Publication 750COM-UM009A-EN-P - May 2017
Chapter 5 Using Explicit Messaging
Formatting a Message to Write a Single Parameter
Figure 22 - Set Attribute Single Message, Configuration Dialog-boxes
The following table identifies the data that is required in each box to configure
a message to write a parameter.
Configuration Tab Example Value Description
Message Type
Service Type
(1)
Service Code
(1)
Class
Instance
(2)
Attribute
(3)
Source Element
Source Length
Destination
CIP Generic (network)
Set Attribute Single
10 (hexadecimal)
93 or 9F (hexadecimal)
(5)
42875 (Dec.)
9 or A (hexadecimal)
Accel_Time_1
(6)
4-bytes
(6)
—
Used to access the DPI Parameter Object in the drive.
This service is used to write a parameter value.
Code for the requested service.
Class ID for the Class ID for the DPI Parameter Object or Host DPI Parameter Object.
Instance number is the parameter number plus the port offset
Attribute number for the Parameter Value attribute.
The tag where the data that is written is stored
Number of bytes of service data to be sent in the message.
Leave blank (not applicable).
Communication Tab Example Value Description
Path
(4)
My_PowerFlex_755T_Drive The path is the route that the message follows.
Tag Tab Example Value Description
Name Single_Write_Message The name for the message.
(1) The default setting for Service Type is ‘Custom’, which enables the entry of a Service Code not available from the Service Type pull-down menu. When choosing a Service
Type other than ‘Custom’ from the pull-down menu, the appropriate hexadecimal value is automatically assigned to the Service Code box, which is dimmed (unavailable).
(2) The instance is the parameter number plus the offset for the port. For example, to write to a 10:1915 [Vref Accel Time 1] of a PowerFlex 755T drive, the instance would be
40960 + 1915 = 42875. See DPI Parameter Object on page 145
(Class code 0x93) or The number of instances depends on the maximum number of faults or events that are
supported in the queue. The maximum number of faults/events can be read in Instance 0, Attribute 2. on page 154 (Class code 0x9F) to determine the instance number.
(3) When the Attribute value is set to ‘9’, the parameter value is written to nonvolatile storage (NVS) of the drive. The drive retains the parameter value even after the drive
power is cycled. Important: When set to ‘9’, the NVS can quickly exceed its lifecycle and cause the drive to malfunction. By setting the Attribute value to ‘A’ it writes the
parameter value to temporary memory, which deletes the parameter value after the drive power is cycled. When frequent write messages are required, we recommended
using the ‘A’ setting.
(4) Click ‘Browse’ to find the path, or type in the name of the device listed in the I/O Configuration folder (for this example, My_PowerFlex_755T_Drive).
(5) See Table 8 on page 96
for limitations of PowerFlex 755T drives when using DPI Parameter Object Class code 0x93 or Host DPI Parameter Object Class code 0x9F for Explicit
Messaging.
(6) In this example, Accel Time 1 is a 32-bit REAL (floating point) parameter that requires the Data Type field to be set to ‘REAL’ when creating the controller tag. To write to a
32-bit integer parameter, set the tag Data Type field to ‘DINT’. For a 16-bit parameter, set the Data Type field to ‘INT’. Also, the Source Length field on the Message
Configuration dialog box must correspond to the selected Data Type in bytes. For example, 4-bytes for a REAL or DINT, or 2-bytes for an INT. See the drive documentation to
determine the size of the parameter and its data type.

Allen-Bradley PowerFlex 755TL Specifications

General

Brand	Allen-Bradley
Model	PowerFlex 755TL
Category	Controller
Language	English