Omron SYSDRIVE RV Series User Manual page 418

Stopping with DC Injection Braking and Zero-speed Control
Output frequency
Frequency
detection 2 or
During run 2
Holding brake operation
When the holding brake's mechanical operation is slow, use DC injection braking (zero-speed control for flux
vector control) until the brakes are fully closed to prevent the brakes from slipping when stopping.
IMPORTANT
Torque Compensation (Flux Vector Control Only)
When flux vector control is used, the torque compensation signals corresponding to the load can be input from
the multi-function analog input terminals in advance to reduce shock, such as that caused by opening and clos-
ing holding brakes. The load size and motoring/regenerating status must be detected at the machine side in
advance. Check that polarity is correct. Incorrect polarity will increase the shock.
Sequence Circuit Configuration
The following diagram shows the sequence circuit configuration for torque compensation.
(Using elevator control circuit)
Torque compensation signal
-210
6
b2-04 (DC injection braking time at stop
(HIGH)
(zero-speed control time at stop): 0.3 to 0.5 s
(LOW)
ON
OPEN
1. When the load cannot be maintained sufficiently using DC injection braking with open-loop vector control
and V/f control, use the dwell functions at stop.
• b6-03 (Dwell frequency at stop): Min. output frequency to 3.0 Hz.
The value must be less than the frequency when frequency detection 2 is OFF (L4-01 − L4-02).
• b6-04 (Dwell time at stop): 0.3 to 0.5 s
[b2-04 (DC injection braking at stop): 0.0 s]
2. If the Inverter and motor must be isolated while stopping using a magnetic contactor, for example in an ele-
vator, fully close the holding brakes and isolate the Inverter during baseblock (during baseblock signal: ON)
as stipulated by law in the EU.
During motor control or DC injection braking (zero-speed control), an Inverter error may occur due to surge
voltage. When a magnetic contactor is used between the Inverter and motor, set L8-07 (Output open-
phase protection) to 1 (enabled).
UP
DOWN
HIGH/LOW
−10 to +10 V
Fig 6.99 Torque Compensation Sequence Circuit Configuration
b2-01 [Zero speed level (DC injection braking
t
starting frequency)]: 0.1 to 3.0 Hz
OFF
b2-02 (DC injection braking current): 50% to 80%
(open-loop vector control, V/f control only)
CLOSE
S1 (Forward run)
S2 (Reverse run)
S6 (Multi-step speed reference 2)
SC
A3
H3-04 (multi-function analog input terminal A3 signal level)
AC
= 1 (−10 to +10 V)
H3-05 (multi-function analog input terminal A3 function
selection) = 14 (torque compensation)
Use H3-06 and H3-07 for fine tuning.