Direction Of Rotation Reversal Using Field Reversal - Siemens 6RA7086-6KS22 Operating Instructions Manual

Function descriptions

9.18.1 Direction of rotation reversal using field reversal

This function is controlled by the binector selected in P580.
The "Direction of rotation reversal using field reversal" has a switch function and defines the field
direction and, if a positive speed setpoint is applied, also the direction of rotation.
Level: 0
1
Changing the logic level of the binector controlling the "Direction of rotation reversal using field
reversal" function initiates an internal sequence which brakes the motor and accelerates it in the
opposite direction.
While the field reversal process is in progress, the logic level of the controlling binector is irrelevant,
i.e. once the function has commenced, it is completed without interruption. Only on completion is
another check made to establish whether the logic level of the controlling binector actually coincides
with the currently selected field direction.
Note:
Only positive speed setpoints are meaningful.
Sequence of control operations when "Direction of rotation reversal using field reversal" is
applied:
1. Drive is rotating in rotational direction 1 (or is at standstill)
2. Logic level of binector controlling the "Direction of rotation reversal using field reversal" changes
3. Internal field reversal process takes place (only if a braking operation has not already been
activated by pushbutton function "Braking with field reversal"):
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
3.10 Enable field firing pulses
3.11 Wait for I
3.12 Waiting time according to P092.i004 (0,0 to 10,0 s, factory setting 3,0 s)
3.13 Enable armature firing pulses
4. Drive brakes and then accelerates in rotational direction 2 (or remains at standstill)
Note:
If the actual speed value polarity is reversed internally as a result of field reversal, P083 (but not
P083=3) is supplied with inverted signal values (see Section 8, Sheet G152). When the ramp-function
generator is in use, it is advisable to set P228=0 (no speed controller setpoint filtering). Otherwise,
initial braking along the current limit may occur in connection with the actual speed value polarity
reversal and setting of the ramp-function generator output (to (reversed) actual speed value (or to
value set in P639) in operating state o1.4).
9-76
Positive field direction is selected
("Close field contactor 1" (B0260) = 1, "Close field contactor 2"
(B0261) = 0)
Negative field direction is selected
("Close field contactor 1" (B0260) = 0, " Close field contactor 2"
(B0261) = 1)
Wait for armature current I
(drive then dwells in operating state ≥ o1.4)
Disable field firing pulses (also causes K0268=0)
Wait for I (K0265) < I
field
Waiting time according to P092.i001 (0.0 to 10.0 s, factory setting 3.0 s)
Open current field contactor (B0260 = 0 or B0261 = 0)
Waiting time according to P092.i002 (0,0 to 10,0 s, factory setting 0,2 s)
Close new field contactor (B0261 = 1 or B0260 = 1)
Reverse polarity of actual speed value (except when P083 = 3 ... EMF as actual speed
value)
Waiting time according to P092.i003 (0,0 to 10,0 s, factory setting 0,1 s)
(K0265) > I
field
(It is possible to exit operating mode o1.4)
= 0 and then armature pulse disable
A
(P394)
field min
(K0268)*P398/100%
field set
SIEMENS AG
SIMOREG DC Master Operating Instructions
05.05
6RX1700-0AD76