Rockwell Automation FlexPak 3000 Digital DC Drive Version 4.3 - Manual (Page 36)

4-16 FlexPak 3000 DC Drive Software Reference
4.3 Speed Reference Ramp
From the speed reference source select block, the value of SPD SOURCE SELECT OUT
(P.193) is amplitude-limited by a minimum/maximum block. This block limits the
reference between
MINIMUM SPEED (P.003) and MAXIMUM SPEED (P.004). You can
modify the results from this block using REVERSE DISABLE (P.015) and AUTO MODE MIN
BYPASS (P.111). The inverter block changes the sign of the signal based on the
forward/reverse signal.
If your automatic speed reference signal is already conditioned, you can bypass the
S-curve block by using
AUTO MODE RAMP BYPASS (P.112). You can also bypass the
amplitude limit block while in auto mode by using AUTO MODE MIN BYPASS (P.111)
If you use the S-curve block, S-curve smoothing rounds the SPD SOURCE SELECT OUT
(P.193) signal. It provides a smoother transition from constant level speed to the
acceleration or deceleration condition. This helps reduce machine wear.
The S-curve block controls how fast the speed reference changes based on the
ACCELERATION TIME (P.001), DECELERATION TIME (P.002), and S - CURVE ROUNDING
(P.014). Within the S-curve block, S - CURVE ROUNDING specifies the maximum rate of
change allowed for ramping. When a step change occurs on the input, the output’s
rate of change increases by
S - CURVE ROUNDING until the acceleration or deceleration
rate is reached. The rate is maintained until the output reaches a distance from the
input where the rate begins decreasing in
S - CURVE ROUNDING intervals.
The speed reference ramp block diagram is shown in figure 4.5.
TRIM REFERENCE SELECT (P.108)
Trim reference
selection. Parameter Range: REGISTER
ANALOG MANUAL
ANALOG IN 1
NETW IN REG 1
NETW IN REG 2
NETW IN REG 3
ANALOG IN 2
Default Setting: REGISTER
Parameter Type: Tunable
OIM Menu Path(s): Drive Reference - Drive Reference Trim
The choices are:
•
REGISTER : The reference is TRIM REF REGISTER (P.107).
•
ANALOG MANUAL : The reference is the analog manual reference input from
terminals 16, 17, and 18 of the Regulator board. Do not select this option if this
input is being used for the analog manual speed reference.
•
ANALOG IN 1 or 2: The reference is from an I/O Expansion kit analog input. These
are only available if an I/O Expansion kit is installed.
•
NETW IN REG 1, 2, or 3: The reference is from a communication register. These
options are available only if a network kit is installed. Note that the network input
registers are updated only when Control Source (P.000) is set to
NETWORK and
the network is active.