NORD Drivesystems BU0590 - Manual (Page 33)

4 Communication
BU 0590 GB-0312 Subject to technical amendments 33
4.2.4.4 Example of telegram structure with parameterisation via PPO1 or PPO2
When transferring parameter orders, it must be taken into account that the slave does not immediately
respond to orders in the parameter channel of the master telegram, but a positive response can be delayed
by one or more communication cycles. The master must therefore repeat the required order until the
corresponding slave response is received. PPO type 1 or PPO type 2 must be selected.
The parameter (P102) "run-up time" (PNU = 102
dec
/ 66
hex
) is to be set to the value 10sec in parameter set 3.
(Only the PKW channel is evaluated). (Only the PKW channel is evaluated.)
As the acceleration time has a frequency-internal resolution of 0.01sec, a parameter value of 10 / 0.01 =
1000 (3E8
hex
) must be transferred for 10 sec.
Procedure:
1) Specify order label ("Change parameter value (array word)" → AK = 7)
2) Select parameter (P 102
dec
= P 66
hex
)
3) Select parameter set 3 (IND = 02)
4) Set parameter value (1000
dec
/ 3E8
hex
)
5) Check response telegram (positive for array word = 4)
The telegram is composed as follows in hexadecimal notation:
word 1 2 3 4
Byte 0 1 2 3 4 5 6 7
Designation PKE PKE IND IND PWE PWE PWE PWE
Value 70 66 02 00 00 00 03 E8
When the order has been fully implemented by the inverter, it responds with (hexadecimal):
word 1 2 3 4
Byte 3 4 5 6 7 8 9 10
Designation PKE PKE IND IND PWE PWE PWE PWE
Value 40 66 02 00 00 00 03 E8
ATTENTION If parameter changes are made (i.e. requests via the PKW area by the control master), care
must be taken that the maximum number of permissible writing cycles to the frequency
inverter EEPROM (100,000 cycles) is not exceeded. I.e. continuous cyclical writing must be
prevented.
For certain applications it is sufficient if the values are only saved in the RAM memory of the
frequency inverter. The corresponding setting is made via parameter (P560) "Save in
EEPROM".