KEB COMBIVERT F5 Reference Manual page 129

UPS Operation
During UPS Operation there is the option for the drive to determine the
direction of travel based on the load to utilize the least amount of power under
a UPS supply. This option is called "Easy Direction" . During the brake release
sequence the drive will measure the motor torque and then command the motor
to travel in the direction of least resistance at the programmed LS10 Battery
Operation Speed. The conditions for determining direction of travel are:
• Less than Balanced = Up
• Greater than Balanced = Down
If the drive is programmed for Digital (0), Binary (1), Absolute Analog (2),
Serial Speed DIN66019 Service 49 (4), Serial Speed DIN66019 Service 50
(5), Serial Binary Speed DIN66019 Service 50 (6) or CAN (7) speed control
modes, LI50 UPS Mode becomes active while UPS Operation is being utilized.
When LI50 is set to default (0), both up and down directions must be signaled
to determine the Easy Direction. When LI50 is set to Easy Direction (1),
either up or down direction can be commanded and the drive will determine
the Easy Direction (signaling both directions is not required). During normal
UPS Operation, (not using the Easy Direction function) the direction of travel
will be as commanded by the controller.
The torque measurement needed for using Easy Direction is determined
when the drive is in the "start delay" mode. If the LT03 Speed Start Delay
timer is set too short, the drive will exit the "start delay" mode and transition
to the "external profile run" mode before the brake lifts, which will result in a 0
lb-ft torque measurement. Likewise, if the controller commands a non-zero
speed value before the brake lifts, a 0 lb-ft torque measurement will occur. By
default, when a 0 lb-ft measurement is taken, the drive will automatically run
the car in the down direction. Therefore, it is important that the LT03 Speed
Start Delay timer is set long enough to allow the brake to lift completely and
that the speed value is sent after the brake has lifted fully. This will ensure that
the drive makes an accurate torque measurement to determine the easiest
direction of travel.
The drive mode can be monitored on the homescreen of the LCD keypad
or DG51 if using Combivis. The torque measurement can be monitored on
diagnostic screen #3 of the LCD keypad or DG05 if using Combivis.
LI - Input Parameters
129