Yaskawa Z1000 AC Drive HVAC - Manual (Page 211)

5.5 Alarm Detection
u Alarm Codes, Causes, and Possible Solutions
Alarms are drive protection functions that do not necessarily cause the drive to stop. After removing the cause of an alarm,
the drive will return to the same status is was before the alarm occurred.
When an alarm has been triggered, the ALM light on the HOA keypad display blinks and the alarm code display flashes. If a
multi-function output is set for an alarm (H2- = 10), that output terminal will be triggered.
Note: If a multi-function output is set to close when an alarm occurs (H2- = 10), it will also close when maintenance periods are reached,
triggering alarms LT-1 through LT-4 (triggered only if H2- = 2F).
TERMS TERMS
Digital Operator: Hand Off Auto (HOA) Keypad JVOP-183
Table 5.11 Alarm Codes, Causes, and Possible Solutions
Digital Operator Display Minor Fault Name
bb
Baseblock
Drive output interrupted as indicated by an external baseblock signal.
Cause Possible Solutions
External baseblock signal was entered via
one of the multi-function input terminals
(S1 to S7).
Check external sequence and baseblock signal input timing.
Note: Baseblock alarm “bb” will not activate a digital output programmed for minor fault
H2-0 = 10. Set H2-0 = 8 or 1B to activate a digital output for “bb”.
Digital Operator Display Minor Fault Name
boL
Braking Transistor Overload Fault
The braking transistor in the drive has been overloaded.
Cause Possible Solutions
The proper braking resistor has not been
installed.
Select the proper braking resistor.
Digital Operator Display Minor Fault Name
bUS
Option Communication Error
• The connection was lost after initial communication was established.
• Assign a Run command frequency reference to the option.
Cause Possible Solutions
Connection is broken or master controller
stopped communicating.
• Check for faulty wiring.
• Correct the wiring.
• Check for disconnected cables and short circuits. Repair as needed.
Option is damaged. If there are no problems with the wiring and the fault continues to occur, replace the option.
The option is not properly connected to the
drive.
• The connector pins on the option are not properly lined up with the connector pins on the drive.
• Reinstall the option.
A data error occurred due to noise.
• Check options available to minimize the effects of noise.
• Take steps to counteract noise in the control circuit wiring, main circuit lines and ground wiring.
• Try to reduce noise on the controller side.
• Use surge absorbers on magnetic contactors or other equipment causing the disturbance.
• Use recommended cables or some other type of shielded line. Ground the shield to the controller side or
on the input power side.
• Separate the wiring for communication devices from the drive input power lines. Install an EMC noise
filter to the drive input power.
Digital Operator Display Minor Fault Name
CALL
Serial Communication Transmission Error
Communication has not yet been established.
Cause Possible Solutions
Communications wiring is faulty, there is a
short circuit, or something is not connected
properly.
• Check for wiring errors.
• Correct the wiring.
• Check for disconnected cables and short circuits. Repair as needed.
5.5 Alarm Detection
YASKAWA ELECTRIC TOEP YAIZ1U 03A YASKAWA AC Drive – Z1000 User Manual 211
5
Troubleshooting