L2: momentary power loss ride-thru, Refer to l2-01 – Yaskawa Z1000U HVAC Matrix Bypass User Manual
Page 183

n
L1-02: Motor Overload Protection Time
Sets the detection time of motor overheat due to overload. This setting rarely requires adjustment, but should correlate with
the motor overload tolerance protection time for performing a hot start.
No.
Name
Setting Range
Default
L1-02
Motor Overload Protection Time
0.1 to 50.0 minutes
1.0 minute
Defaulted to operate with an allowance of 150% overload operation for one minute in a hot start.
illustrates an example of the electrothermal protection operation time using a general-purpose motor operating at
the value of E1-06, Motor Base Speed, with L1-02 set to one minute.
During normal operation, motor overload protection operates in the area between a cold start and a hot start.
• Cold start: Motor protection operation time in response to an overload situation that was suddenly reached when starting a
stationary motor.
• Hot start: Motor protection operation time in response to an overload situation that occurred during sustained operation at
rated current.
Operation time (minutes)
Cold start
Hot start
Motor current (%)
E2-01 = 100% motor current
10
7
3
1
0.4
0.1
0
100
150
200
Figure 5.40 Motor Protection Operation Time
u
L2: Momentary Power Loss Ride-Thru
n
L2-01: Momentary Power Loss Operation Selection
When a momentary power loss occurs (DC bus voltage falls below the level set in L2-05), the drive can automatically return
to the operation it was performing prior to the power loss based on certain conditions.
No.
Name
Setting Range
Default
L2-01
Momentary Power Loss Operation Selection
0 to 2
2
Setting 0: Disabled
If power is not restored within 15 ms, a Uv1 fault will result and the motor coasts to stop.
Setting 1: Recover within L2-02
When a momentary power loss occurs, the drive output will be shut off. If the power returns within the time set to parameter
L2-02, the drive will perform Speed Search and attempt to resume operation. If the power does not return within this time, it
will trigger a Uv1 fault.
Note:
L2-02 value is dependent on drive model selection and is not accessible.
Setting 2: Recover as long as CPU Has Power
When a momentary power loss occurs, the drive output will be shut off. If the power returns and the drive control circuit has
power, the drive will attempt to perform Speed Search and resume the operation. This will not trigger a Uv1 fault.
Notes on Settings 1 and 2
“Uv” will flash on the operator while the drive is attempting to recover from a momentary power loss. A fault signal is not
output at this time.
5.8 L: Protection Functions
YASKAWA SIEP YAIZ1D 01A Z1000U HVAC MATRIX Drive Bypass Technical Manual
183
5
Programming