Inovance H3U Series - Communication Settings and DIP Switches

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1 Overview
1
1.2 PLC Operating Principle
• [1]: The three channels of AB phase counters support differential or single-ended inputs.
• [2] High-speed outputs are only applicable to models with transistor outputs. H3U standard models use open-drain
outputs. Motion models use differential outputs.
• [3]: 3-axis output is dened. Each axis includes two groups of differential outputs, which can serve as AB phase
outputs in the CW/CCW output format or pulse plus direction mode.
• [4]: The H3U local extension module does not support the H2U-XP extension module, but supports the AM600
local extension module.
• [5]: For the motion control functions of the H3U-PM model, see
“Chapter 7 Motion Control” on page 466
.
• [6]: For application of the electronic cam of the H3U-PM model, see
“Chapter 8 Electronic Cam” on page 563
.
1.2 PLC Operating Principle
After a programmer downloads a designed and compiled ladder chart program to the PLC memory, the PLC scans
the user program.
When running, the PLC mainly detects the X input, scans and operates the user program, refreshes the status of
other elements, and outputs the Y cache status to the Y hardware port in cycles. User program scanning is the
core task. The process is shown in the following gure.
Read the status of the X port
Refresh the T and C components
X1
X2
Y1
(Y1)
Scan and execute the ladder logic program
Save the computed status of Y, M, S and
other soft components to the internal buffer
M1
(M3)
Y1
Output the Y status to the hardware port
X2
Network 1
Network 2
Before executing a user program, the PLC reads and stores the X hardware port status to the X variable buffer.
The user program is scanned based on network blocks. A network block is a group of elements connected through
wires. See the two networks in the preceding gure. The calculation is executed from the rst network to the
last one. The "contact" statuses of elements in each network are logically calculated and synthesized one after
another from the left to the right. The PLC outputs the result to the "coil" of the element, or determines whether to
perform an operation based on the logic.
In the ladder chart, the part on the left now serves as a "live wire" with the default (potential) state of ON. Each
time an element is passed, the logic operation result transitory status is refreshed. The intermediate operation
result transitory status is sometimes called a "ow". The intermediate logic operation result status is ON; that is,
the "ow" is valid. The output status of this network is the status of the ow that outputs electricity. If the right most
indicates an operation and the ow is valid, the operation is performed; otherwise, the operation is not performed.