Omron GRT1-ECT SmartSlice, Руководство по эксплуатации

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8 Sysmac Studio
GRT1-series EtherCAT Communication Unit - Operation Manual
8-3
Calcula
ting
I/O Refresh
T
ime
8
8-3
-1 Intr
oduction
8-3 Calculating I/O Refresh Time
This section describes the calculation of the I/O Refresh Time for a SmartSlice configuration.
The I/O Refresh Time is the time required to process the Outputs, transmitting the EtherCAT data and
processing the Inputs.
The I/O Refresh Time depends on the hardware configuration of the Slave.
For more information refer to manual W501 (NJ-series Software user’s Manual).
To calculate the I/O Refresh Time:
1.
Define the SmartSlice configuration.
2.
List for all available units the input size and the output size.
The input- and output size are the number of bits required for the signal.
Additional information
• One digital Input or Output has a I/O size of 1 bit. (On / Off)
• One Analog Input or Output has a I/O size of 2 bytes.
• One Counter Unit has an Input size of 6 bytes and an Output size of 6 bytes.
• 1 byte = 8 bits
3.
Calculate the total number of bytes for Inputs, named IN_size.
IN_size = Size Digital Size Analog Size
Communication Unit status
• Size Digital Inputs (DI)
The IN_size is in bytes, the actual unit is bits, so conversion from bits to bytes is required.
• Add all digital inputs together.
• Convert the result from bits to bytes.
= (Total number of DI / 8) and then round to next integer value.
• Size Analog Inputs (AI)
Each analog SmartSlice Input uses 2 bytes.
One analog SmartSlice unit has 2 analog inputs and therefore an Analog Inputs Size of 4
bytes.
• Add all Analog inputs together.
• Multiply AI by 2.
• Size Counter Inputs (CI)
Each Counter SmartSlice Unit uses 6 bytes.
• Add all Counter Units together.
• Multiply AI by 6.
8-3-1 Introduction
8-3-2 Calculation I/O Refresh Time
Calculate the IN_size