19
Performance Section 1-7
Processing Cycle of MC
Unit
The MC Unit holds Control Cycle for the entire Unit and Communication Control Cycle.
The system software calculates each control cycle, and it operates when "Unit
cycle: Communications cycle" is "1:1" or "2:1".
Calculation methods for each control cycle are as follows:
• Calculates the Unit Cycle
• Calculates the Communication Cycle
• Adjusts and matches the Unit Cycle and Communications Cycle.
Calculation Method for
Unit Cycle
Basic formula for calculating Unit Cycle is shown below:
Unit Cycle [
µs] = (115.0 × No. of axes)+(165.0 × No. of motion tasks × No.
of parallel branches) + (0.3
× No. of general allocated words) + 350.0 --- (1)
• No. of axes:No. of axes allocated in [P1AA01:Physical axis setting] (Sum
of virtual and actual axes)
• No. of Motion tasks: P00001 [No. of Motion tasks]
• No. of parallel branches: P00002 [No. of parallel branches]
• No. of general allocated words:
No. of Allocated words to be used as general purpose I/O (Sum of inputs
and outputs)
Note for P00003 [Unit Scan time]
When P00003 [Unit Scan time] is greater than the result of the formula (1), the
formula (2) below is to be used.
Unit Cycle [
µs] = P00003 × 1000 ---(2)
Time lag per axis (Interpolation) 0 Time delay caused when interpolation is per-
formed with one motion task. No delay between
axes.
Time lag per axis (Independent operation)
0 Time delay caused when every motion task with
one axis is started simultaneously. No delay
between axes.
Minimum operation time Tm Minimum operation time required to stay in Pass
Mode.
The same as the Unit Cycle.
Minimum traverse reversal time Tm Minimum time required for reversal operation of
traverse command. The same as the Unit cycle.
External input
response time
Unit Built-in general
input
Tm or less Time from accepting the Unit built-in general
input until it is reflected to input variables. It is
the same or less than Unit cycle.
Unit Built-in deceleration stop input
2Ts+Tm+0.625ms~2Ts+Tm+
Ts+0.625ms+Tm
Time from receiving deceleration stop input until
the operation command is output to the control
loop of the servo driver
CW/CCW limit origin
proximity input
4Ts+Tm+0.625ms~4Ts+Tm+
Ts+0.625ms+Tm
Time from when the servo driver recognizes the
input until the operation command is output to
the control loop of the servo driver.
Synchronization delay
MECHATROLINK
slaves
4Ts+Tm+0.625ms~4Ts+Tm+
Ts+0.625ms+Tm
Time from when the slave recognizes the input
until the operation command is output to the
control loop of the servo driver.
Counter latch
startup time
W + NS115 [(20ms/Tm) ×5+5] ×Tm+
Ts×3+4ms~[(20ms/Tm) ×8+5]
×Tm+Ts×3+4ms
Time taken by the MC unit to become able to
execute the counter latch after issuing a LATCH
command. Refer toCalculation Method for the
Counter Latch Startup Time on page 20.
Unit Ver. 2.0 or Later
When the starting and target
positions are not specified:
Tm × 3 + Ts × 3 + 4 ms
Item Performance data Description