Yaskawa iQpump Micro - Manual (Page 110)

H2 Multi-Function Digital Output Settings
H2-oo
Setting
Function Description
89 Output I Limit
Closed: Drive output speed is being limited due to the output current limit or the single phase foldback
regulator.
The drive displays a message on the keypad when the drive is in output current limit.
Digital Operator Display Message
Current Limit Foldback
(CUr)
Displayed when drive output speed is being limited due to the output current limit. Reduce the load or replace with
higher capacity drive.
n Speed Follower Deceleration Time Switchover
The iQpump Speed Follower will attempt to match the speed of the Lead Drive after the Lag Drive Fixed Speed Delay.
Consider a scenario wherein the system needs help from an idle drive to maintain system pressure. When the idle drive is
called to run, the difference between the setpoint and the feedback may be too small to make the drive accelerate faster. In
such cases, the system is configured with these settings:
• Set for Lag Drive Speed Follower
• Add Pump method is Frequency Reference
• Frequency Reference setting close to the maximum frequency
The system will drop the speed after the Lag Drive Fixed Speed Delay expires in order to follow the output frequency of the
previously idle drive. This transition may cause unwanted pressure drops. A longer deceleration time will be activated on the
lag drives when the system switches the drive that is being followed. The longer deceleration time will be effective for a
programmable setting, after which the regular deceleration time is used.
Functional Operation
If P9-05 = 3 (Follow Lead Spd), the lag drive will use the network information and the lead drive output speed as its frequency
reference. The lag drive final speed reference is affected by (Lag Follower Gain, P9-30) and then by (Lag Follower Bias,
P9-31).
Lag Drive Speed = ( Lead Drive Speed x Lag Follower Gain ) + Lag Follower Bias
When P9-33 > 0.0 sec, an alternate deceleration time (Lag Follower Decel, P9-32) is used when the drive switches from the
latched speed (Lag Fixed Delay, P9-07) to the new Lead drive output frequency. The deceleration time is active for the duration
set in P9-33, Lag Follower Deceleration Time Active Time, and will switch back to the regular deceleration rate when it
expires.
Note: Parameter functionality stated below only applies when P1-01 = 3 (MEMOBUS Network)
Related Parameters
No. Name Description Values
P9-05 Lag Drive Mode
Determines the functionality of the lag drives.
0: Fixed speed. The drive runs at the P9-06 setting after the time set in P9-07
expires.
2: Turn off. The drive stops running when it switches to a lag drive after the time
set in P9-07 expires.
3: Follow Lead Speed. The drive will follow the speed of the current lead drive,
applying P9-30 gain and P9-31 bias.
Default: 0
Range: 0, 2, 3
P9-07 Lag Fixed Speed Delay
Specifies how long speed is latched before performing the function specified in
P9-05 when the drive changes from a lead to a lag.
Default: 5 s
Min.: 0
Max.: 1000
P9-30 Lag Drive Speed Follower Gain
Sets the gain to be applied to the speed of the current lead drive when P9-05 is set
to 3. The bias to be applied is set in P9-31.
Default: 100.0%
Min.: 0.0
Max.: 300.0
P9-31 Lag Drive Speed Follower Bias
Sets the bias to be applied to the speed of the current lead drive when P9-05 is set
to 3. The gain to be applied is set in P9-30.
Default: 0.00 Hz
Min.: -60.0
Max.: 60.0
P9-32
Lag Follower Deceleration
Time
Sets the deceleration time when the P9-33 timer is running and the drive is running
as Lag Drive Speed Follower (P9-05 is set to 3).
Default: 60.0 s
Min.: 0.0
Max.: 1000.0
P9-33
Lag Follower Deceleration
Time Active Time
Sets the time during which the deceleration time set in P9-32 is effective. The drive
will use the standard deceleration rate when it expires.
Setting this parameter to 0.0 disables the function.
Default: 0.0 s
Min.: 0.0
Max.: 360.0
4.7 iQpump Presets and Functions
110 YASKAWA TOEP YAIQPM 03B YASKAWA AC Drive - iQpump Micro User Manual