Toshiba 18 - 1250 A - Manual (Page 78)

TE Series Digital Solid State Soft Starters 18 – 1250A
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ALWAYS shuts the starter down WITHOUT Decel (as in setting 1
above) even if F025 is set to 2.
F025 = Begin Decel Level (BDL)
Factory Setting = 60%
Range = 0 - 100% of line voltage
Use to drop voltage to a level where there is a noticeable effect
on motor torque during Decel mode. Generally, systems with
high head pressure need to start Decel near the top of the ramp
(85-95%). Low head systems can drop to lower settings (50-
60%). System conditions vary greatly by pump type, pipe size
and system head. Some experimentation with settings may be
necessary.
F026 = Decel Shut Off Voltage
Factory Setting = 30%
Range = 0 to (BDL -1)%
Sets the level where the starter is turned off, corresponding to
where motor torque during Decel is no longer effective. Always
set this function lower than the setting of F026, Begin Decel
Level (this function is restricted from being less than F026
minus 1%). This function is used to shut the motor off once the
check valve closes. Again, because systems vary greatly this
setting may require adjustment several times. If you cannot
hear or see the check valve close, observe fluid pressure or
flow if available.
F027 = Decel Ramp Time
Factory Setting = 10 seconds
Range = 1 - 60 seconds
Sets the maximum time for the deceleration ramp to go from the
Begin Decel Level setting (F026) to the Decel Shut Off Voltage
(F027). This function is used to dampen the effect of reducing
pump torque as much as possible. If the check valve still slams
at the end of ramp, try extending this time function a little. Since
motor heating increases as voltage is lowered, the setting
should not exceed the time necessary to achieve the
deceleration effect.
ƒ NOTE:
When using the Decel function, count these cycles as additional
“starts” when determining maximum starts-per-hour.
Other Applications:
Another common application for Decel control is on material handling
conveyors as a means to prevent sudden stops that may cause
products to shift, fall over or to bump into one another.
In overhead crane applications, Soft Stopping of the Bridge or Trolley
can prevent loads from beginning to over swing on sudden stops.