Error 40 Troubleshooting
According to the technical manual Error 40 (By wave current limiting fault) is caused by either the Drive model being of too small power class or due to the load being too heavy or locked- rotor occurring on the motor.
Other common Causes however include the following:
- Poor Pump/Motor insulation or poor Cable insulation.
- Too long cable distance between Drive and Pump/Motor causing too much leakage current.
- VF Shock (Abnormal Load / Transient Overcurrent Protection) – Caused by instantaneous currents of more than 2 times the rated Drive current.
Some tests that can be done to try and pinpoint the issue include the following:
- Test whether the Motor Direction is correct – can be done without changing wiring, or via parameter setting:
- For Solar Drive (Single Line Keypad Model) set F0-09 = 1 (Reverse) and check whether it resolves the issue. If not, set F0-09 back to = 0 (Forward). Note that if F0-02=1 (Terminal Control), F0-09 cannot be changed, so first set F0-02=0 (Keypad Control) before setting it to Reverse Direction.
- For VSD or Solar Drive (Double Line Keypad Series) set b0-18 = 1 (Reverse) and check whether it resolves the issue. If not, set b0-18 back to = 0 (Forward). Note that if b0-02=1 (Terminal Control), b0-18 cannot be changed, so first set b0-02=0 (Keypad Control) before setting it to Reverse Direction.
- Test for VF Shock by setting the following parameters (make note of original values in order to change them back to the original values after the test):
- For Solar Drive (Single Line Keypad Model) set F3-10 = 64 (VF Over Excitation Gain) and F3-11 = 40 (VF Oscillation Suppression Gain) – make note of original values. If the Motor/Pump then runs without an error it can be confirmed as VF Shock causing the error. If this has no effect, set the values for these parameters back again and check the insulation of the pump/motor and cable.
According to experience in the use of submersible pumps, the possibility of leakage current is relatively large (high leakage current will not show a higher current reading on the Drive). Using an Output reactor could assist in resolving this and provide protection to the Drive and motor – submersible pumps generally have very poor power factors, so ideally size the Drive larger than the pump motor rating.
