Yaskawa iQpump Programming Manual - Manual (Page 18)

18 YASKAWA TM.iQp.02 iQpump Drive Programming Manual
◆ b2 DC Braking
The DC Braking Group contains parameters associated with the DC injection braking feature. Parameters involving the starting
frequency, current level, braking time, and motor pre heat current level are located here.
■
b2-01 DC Injection Braking Start Frequency
Setting Range: 0.0 to 10.0 Hz
Factory Default: 0.5 Hz
Parameter b2-01 sets the output frequency where the iQpump drive begins DC Injection during Ramp to stop in order to lock the rotor
of the motor and established the end point of the ramp. If b2-01 < E1-09 (Minimum Frequency), then DC Injection begins at E1-09.
Parameter b2-01 also determines the output frequency that the iQpump drive must be at or below before a Zero Speed condition is
considered true. This affects any digital output configured as a Zero Speed signal (H2-0x = “1: Zero Speed”).
Figure 1.13
Figure 13 DC Injection Braking During Stopping
■ b2-02 DC Injection Braking Current
Setting Range: 0 to 100%
Factory Default: 50%
The level of DC Injection Braking Current affects the strength of the magnetic field attempting to lock the motor shaft. Increasing the
level of current will increase the amount of heat generated by the motor windings and should only be increased to the level necessary to
hold the motor shaft. DC Injection current is set in percentage of the iQpump drive rated output current. iQpump drive rated output
current is stated on the iQpump drive nameplate.
■
DC Injection Braking Time
Setting Range: 0.00 to 10.00 sec
Factory Defaults: b2-03 = 0.00 sec and b2-04 = 0.50 sec
The iQpump drive can be programmed to automatically DC Inject for a predetermined amount of time prior to accelerating to speed (b2-
03) and/or at the end of a Ramp to stop (b2-04). Parameter b2-03 can be used to stop a rotating motor prior to attempting acceleration (i.e.
a wind milling fan). If DC Injection braking at start or Speed Search is not enabled, attempting to drive a spinning motor may cause
nuisance tripping.
Parameter b2-04 can be used to resist any residual motion of the load after the deceleration has finished.
Figure 1.14
Figure 14 DC Injection Braking During Starting and Stopping
Parameter No. Parameter Name
b2-03 DC Injection Braking Time at Start
b2-04 DC Injection Braking Time at Stop
Output Frequency
t
b2-01
DC injection
| |
b2-04
ime
Output Frequency
DC injection
b2-03 b2-04