Maxi MWHE20 - Page 59

TROUBLE SHOOTING
7-17
13. “Er2” Remote keypad communications error
Problem a communications error occurred between the remote keypad and the inverter.
Possible Causes
What to Check and Suggested Measures
1. Break in the
communications cable
or poor contact.
Check continuity of the cable, contacts and connections.
→ Replace the cable.
2. A high intensity noise
was given to the
inverter.
→ Check if appropriate noise control measures have been
implemented (e.g. correct grounding and routing of control and
main circuit wires).
→ Improve noise control.
3. The remote keypad
malfunctioned.
Check that alarm Er2 does not occur if you connect another remote
keypad to the inverter.
→ Replace the remote keypad.
4. The RS485
communications card
malfunctioned.
Check that alarm Er2 does not occur even if you connect another
remote keypad to the inverter.
→ Replace the card.
14. “Er3” CPU error.
Problem a CPU error (e.g. erratic CPU operation) occurred.
Possible Causes
What to Check and Suggested Measures
1. A high intensity noise
was given to the
inverter.
Check if appropriate noise control measures have been implemented
(e.g. correct grounding and routing of control and main circuit wires).
→ Improve noise control.
2. The printed control
circuit board in the
inverter
malfunctioned.
→ Replace the board.
15. “Er6” Operation protection
Problem an error occurred due to incorrect operation of the motor.
Possible Causes What to Check and Suggested Measures
1. The STOP key was
pressed when H96 = 1
or 3.
→ Change the setting for H96 so that the STOP key priority function
is invalid to ensure that the inverter does not operate
unexpectedly.
2. The start check
function was activated
when H96 = 2 or 3.
Check that Er6 occurs when:
- The power is switched on
- An alarm is released (by pressing the PRG/RESET key or
turning reset alarm (RST) on).
- The link command (LE) has switched the inverter operations.
→ Reconsider the running sequence to avoid input of the run
command when Er6 has occurred.
→ Change the setting for H96 so that the STOP key priority
functions is invalid to ensure the inverter does not operate
unexpectedly. (To reset the alarm, turn the run command off.)