YASKAWA Z1000U Technical Manual page 222

6.5 Alarm Detection
HOA Keypad Display
Faulty communication wiring or an existing short
circuit.
Communication data error occurred due to noise.
Communication Error timeout time not set
properly.
Controller is not sending data soon enough to stop
the timeout.
HOA Keypad Display
AL16
Cause
Incorrect phase rotation while Z1-52 is set to 1 in
Bypass Mode.
HOA Keypad Display
AUv
Cause
The power supply voltage is low.
A phase loss occurred in the input power supply.
Voltage detection failed.
HOA Keypad Display
bb
Cause
External baseblock signal was entered via one of
the multi-function input terminals (S1 to S8)
HOA Keypad Display
bUS
Cause
Connection is broken or master controller stopped
communicating
Option is damaged
The option is not properly connected to the drive
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• Check for faulty serial communication wiring
• Correct the wiring
• Check for disconnected cables and short circuits and repair as needed.
• Check the various options available to minimize the effects of noise
• Counteract noise in the control circuit, main circuit, and ground wiring
• Use only recommended cables or other shielded line. Ground the shield on the controller side
• Ensure that other equipment such as switches or relays do not cause noise. Use surge suppressors
if required
• Separate all communication wiring from power lines. When the lines must cross, make the lines
cross at a right angle to minimize noise coupling.
Verify the setting of the serial communications fault time (Z3-06) is set properly.
Verify the scan rate in the controller that is communicating with the bypass controller is proper. Adjust
as necessary.
Input Phase Rotation
Check the sequence (phase rotation) of the input wiring to the bypass package.
Power Supply Undervoltage
The input power supply voltage became equal to or lower than the Input Power Supply Undervoltage
Detection Level (L2-21).
200 V Class: Approximately 150 Vrms
400 V Class: Approximately 300 Vrms
Increase the power supply voltage.
Check the input power supply for phase loss or an imbalance in the interphase voltages. Investigate
and correct the cause and then reset the fault.
Correctly wire r1/ l11, s1/ l21, and t1/ l31.
Baseblock
Drive output interrupted as indicated by an external baseblock signal.
Check external sequence and baseblock signal input timing.
Option Communication Error
• The connection was lost after initial communication was established.
• Assign a Run command frequency reference to the option.
• Check for faulty wiring.
• Correct the wiring.
• Check for disconnected cables and short circuits. Repair as needed.
If there are no problems with the wiring and the fault continues to occur, replace the option.
• The connector pins on the option are not properly lined up with the connector pins on the drive.
• Reinstall the option.
YASKAWA SIEP YAIZ1D 01C Z1000U HVAC MATRIX Drive Bypass Technical Manual
Fault Name
Minor Fault Name
Possible Solution
Minor Fault Name
Possible Solution
Minor Fault Name
Possible Solutions
Minor Fault Name
Possible Solutions