Morgensen MSI350 Series, Руководство пользователя, Страница: 270 / 388

270
is lower than 1.5 Ω ).
2. Do not connect the inverter and motor to the same ground terminal as the upper computer. It is
recommended that you connect the inverter and motor to the power ground, and connect the
upper computer separately to a ground stud.
3. Try to short the signal reference ground terminal (GND) of the inverter with that of the upper
computer controller to ensure that ground potential of the communication chip on the control board
of the inverter is consistent with that of the communication chip of the upper computer.
4. Try to short GND of the inverter to its ground terminal (PE).
5. Try to add a safety capacitor of 0.1 μ F on the power terminal of the upper computer (PLC, HMI,
and touch screen). During this process, pay attention to the voltage of the power supply and the
voltage endurance capability of the capacitor. Alternatively, you can use a magnet ring (Fe-based
nanocrystalline magnet rings are recommended). Put the power L/N line or +/- line of the upper
computer through the magnet ring in the same direction and wind 8 coils around the magnet ring.
7.7.3 Failure to stop and indicator shimmering due to motor cable coupling
Interference phenomenon
1. Failure to stop
In an inverter system where an S terminal is used to control the start and stop, the motor cable and
control cable are arranged in the same cable tray. After the system is started properly, the S terminal
cannot be used to stop the inverter.
2. Indicator shimmering
After an inverter is started, the relay indicator, power distribution box indicator, PLC indicator, and
indication buzzer shimmers, blinks, or emits unusual sounds unexpectedly.
Solution
1. Check and ensure that the exception signal cable is arranged 20 cm or farther away from the
motor cable.
2. Add a safety capacitor of 0.1 μ F between the digital input terminal (S) and the COM terminal.
3. Connect the digital input terminal (S) that controls the start and stop to other idle digital input
terminals in parallel. For example, if S1 is used to control the start and stop and S4 is idle, you
can try to connect connect S1 to S4 in parallel.
Note: If the controller (such as PLC) in the system controls more than 5 inverters at the same time
through digital input terminals (S), this scheme is not available.