Yaskawa AC Drive Z1000 AC Drive HVAC Fan - Manual (Page 30)

Output
frequency
Time
DC Injection
Braking
b2-04 b2-13
Short Circuit
Braking
E1-09 Min. Frequency
b2-01 Zero Speed Level
Figure 1.9 Short-Circuit Braking at Stop in OLV/PM
Note: If b2-01 is set to a smaller value than parameter E1-09 (minimum frequency), then DC Injection Braking will begin as soon as the frequency
falls to the value set to E1-09.
n b2-02: DC Injection Braking Current
Sets the DC Injection Braking current as a percentage of the drive rated current. The carrier frequency is automatically reduced
to 1 kHz when this parameter is set to more than 50%.
No. Name Setting Range Default
b2-02 DC Injection Braking Current 0 to 100% 50%
The level of DC Injection Braking current affects the strength of the magnetic field attempting to lock the motor shaft.
Increasing the current level will increase the amount of heat generated by the motor windings. Do not set this parameter higher
than the level necessary to hold the motor shaft.
n b2-03: DC Injection Braking Time at Start
Sets the time of DC Injection Braking at start. Used to stop a coasting motor before restarting it or to apply braking torque at
start. Disabled when set to 0.00 s.
No. Name Setting Range Default
b2-03 DC Injection Braking Time at Start 0.00 to 10.00 s 0.00 s
Note: Before starting an uncontrolled rotating motor (e.g., a fan motor driven by windmill effect), use DC Injection or Speed Search to stop the
motor or detect motor speed before starting it. Otherwise, motor stalling and other faults can occur.
n b2-04: DC Injection Braking Time at Stop
Sets the time of DC Injection Braking at stop. Used to completely stop a motor with high inertia load after ramp down. Increase
the value if the motor still coasts by inertia after it should have stopped. Disabled when set to 0.00 s.
No. Name Setting Range Default
b2-04 DC Injection Braking Time at Stop 0.00 to 10.00 s 0.00 s
n b2-09: Motor Pre-Heat Current 2
Determines the percentage of motor rated output current that will be sued for the motor pre-heat function. Thid function can
be useful in applications whre the motor sits for extended periods of time in humid conditions. Motor pre-heating can only be
initiated by closing a digital input programmed as a Motor Pre-Heat 2 (H1-oo = 50).
No. Name Setting Range Default
b2-09 Motor Pre-Heat Current 2 0 to 100% 5%
n b2-12: Short Circuit Brake Time at Start
Short Circuit Braking can be used in OLV/PM. Shorting all three motor phases produces a braking torque in the motor and
can stop a coasting motor before starting it again. Disabled when set to 0.00 s.
No. Name Setting Range Default
b2-12 Short Circuit Brake Time at Start 0.00 to 25.50 s 0.00 s
Note: Short Circuit Braking cannot prevent a PM motor from being rotated by an external force. Use DC Injection to prevent the load from rotating
the motor.
1.2 b: Application
30 YASKAWA ELECTRIC SIEP YAIZ1U 03A YASKAWA AC Drive – Z1000 Programming Manual