74 FP5/GP5 User’s Manual
Chapter 3 - Programming Features
FP5/GP5 Operation
· Over/undertorque Detection Level (n078, Torq Det Level)
Sets the torque detection current level in units of 1%
Inverter rated current: 100%
Factory default: 160%
· Over/undertorque Detection Time (n079, Torq Det Time)
The over/undertorque detection delay time inserts a delay, between the time
motor current exceeds or falls below the over/undertorque detection current
level (n078) and when the over/undertorque detection function is enabled.
Factory default: 0.1 second
If the time during which motor current exceeds or falls below the over/
undertorque detection level (n078) is longer than the over/undertorque
detection time (n079), the over/undertorque detection function is enabled.
Tripless Operation
When starting into a coasting motor, use the speed search command or
DC injection braking at start, to prevent a drive trip and motor burnout.
· Speed search
This function allows the restart of a coasting motor without the neces-
sity to stop. It is useful during inverter bypass operation, when switch-
ing between the motor receiving power directly from the line to the
inverter.
Set the multi-function contact input selection (n036 to n40) to “SpdSrch
(MAXFREQ)” (start search command from maximum output fre-
quency) or “SpdSrch (SETFREQ)” (start search command from the set
frequency).
Build a sequence so that the FWD (REV) run command is input at the
same time as the search command, or after the search command. If the
run command is input before the search command, the search command
is not effective. Below is a timing diagram of the search command input:
FWD (REV) Run Command
Speed Search Command
Max. Output Frequency or
Frequency Reference at
Run Command Input
Output Frequency
ON
ON
Speed Search
Speed Search Start
(Condition: Inverter Output Current
≥
n056 Speed Search Level)
Min. Baseblock
Operation
Time (n057)
Speed Detection Agree
(Condition: Inverter Output Current
< n056 Speed Search Level)
Figure 44 Search Command Input Timing Diagram
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