If The Direction Of The Motor Rotation Is Reversed; If The Motor Does Not Put Out Torque Or If Acceleration Is Slow; If The Motor Operates At Higher Speed Than The Frequency Reference - YASKAWA Varispeed E7 Instruction Manual And Parameter Description

When using a 2-wire control, set the multi-function input terminal (H1-01 through H1-05, terminals S3 to S7)
to a value other than 0.
The frequency reference is too low.
If the frequency reference is set below the frequency set in E1-09 (Minimum Output Frequency), the Inverter
will not operate. Raise the frequency reference to at least the minimum output frequency.
The motor stops during acceleration or when a load is connected.
The load may be too heavy. The Inverter has a stall prevention function and an automatic torque boost func-
tion, but the motor responsiveness limit may be exceeded if acceleration is too rapid or if the load is too heavy.
Lengthen the acceleration time or reduce the load. Also consider increasing the motor capacity.
The motor rotates in one direction only.
"Reverse run prohibited" is selected. If b1-04 (Prohibition of Reverse Operation) is set to 1 or 3(reverse run
prohibited), the Inverter will not accept reverse run commands. To use both forward and reverse operation, set
b1-04 to 0 or 2.

If the Direction of the Motor Rotation is Reversed

If the motor operates in the wrong direction, the motor output wiring is faulty. When the Inverter T1(U),
T2(V), and T3(W) are properly connected to the motor T1(U), T2(V), and T3(W), the motor operates in a for-
ward direction when a forward run command is executed. The forward direction depends on the manufacturer
and the motor type, so be sure to check the specifications.
The direction of rotation can be reversed by switching two wires among U, V, and W, or use constant b1-04 to
reverse output direction (in V/f mode only).

If the Motor Does Not Put Out Torque or If Acceleration is Slow

The stall prevention level during acceleration is too low.
If the value set for L3-02 (Stall Prevention Level during Acceleration) is too low, the acceleration time will be
very long. Check to be sure that the set value is suitable.
The stall prevention level during running is too low.
If the value set for L3-06 (Stall Prevention Level during Running) is too low, the speed may drop already at
low output torque. Check to be sure that the set value is suitable.

If the Motor Operates at Higher Speed than the Frequency Reference

The analog frequency reference bias or gain setting is wrong.
The frequency reference bias or gain set in constant H3-03 or H3-02 influence the frequency reference. Check
to be sure that these set values are suitable.
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