NORD Drivesystems BU0510 - Manual (Page 68)

POSICON position control for NORD frequency inverters, SK 530E and above
68 Subject to technical alterations BU 0510 GB-3911
Fig. 9: Flying Saw
6.9.1 Determination of acceleration path and initiator position
The distance of the initiator from the point at which the sawing process is to begin corresponds to double the
value of the acceleration path for the saw drive. During the acceleration process the belt drive travels back for
double the distance of the saw drive. For the calculation of the initiator position the corresponding speed ratios
between the drive units and gearing factors must be taken into account. The minimum acceleration path which
is entered in (P613[-63] is calculated as follows:
P613[-63] > 0.5 * n
Slave_max
[rev/s] * T
Acceleration
[s] with
T
Acceleration
[s] = P102[s] * F
Slave_max
/ P105 and
n
Slave_max
= F
Slave_max
/ Number of pole pairs
P608[-xx]/P607[-xx]
13
= (Ü
Gear Slave
* D
Master
) / (Ü
Gear Master
* D
Slave
)
∆P
INI
= 2 * P613[-63][rev] * π *D
slave
/ Ü
Gear Slave
(n = Speed, T=Time, F=Frequency, Ü=Speed ratio
D=Diameter of gear unit output, ∆P
INI
=Minimum distance from initiator)
If the set acceleration path is smaller than that which is necessary, the error message E13.5 "Flying saw
acceleration" is triggered. A check is also made as to whether the sign of the acceleration path matches the
sign of the master speed. If this is not the case, the error message E13.6 "Flying saw value false" is triggered
after the start command is activated.
13
The speed ratio is entered into the parameter of the encoder which is not used, or for SK 540E and above, into Array [-05]
n
Slave
= n
Master
n
Slave
=0
"Drive synchronised" output
"Start Flying Saw" input
“
"Disable synchronous operation" input
P613[-63]
INI – Position = 2 x P613[-63]
Slave standby position
Starting point of sawing
process
Acceleration starts
Brake and return
to starting position
P
Master drive
Slave drive
Initiator:
"Start Flying Saw"
Initiator:
"Disable synchronous
operation"
Starting point of sawing process
Initiator:
"Disable synchronous operation"