Example 3: Array Treatment - Danfoss 5000 Flux Manual

Example 3: Array treatment

Example for addressing an array parameter.
Assumption: as in the previous examples, the VLT
is running. Now, the variable process data are not
to be preconfigured on the display, but are to be
configured through the PCV portion (of the PPO2)
instead.
For example, only the PCD 1 will be configured for
the display of the motor current.
Master telegram (PPO2)
The master sends the following telegram to the
VLT:
Byte
PCA 1 and 2
PCV I N D 3 and 4
PVA 5 and 6
PVA 7 and 8
CTW 9 and 10
MR V 11 and 12
PCD PCD 1 13 and 14
PCD 2 15 and 16
PCD 3 17 and 18
PCD 4 19 and 20
PCA
Hex 7 corresponds to "change parameter value
(array word)" in the RC portion of the PCA. Hex 394
= 916 decimal.
The parameter 916 is used to configure the PCD-
Read. Since a subindex is required to configure
the parameter, the parameter 916 is an array.
I N D
Hex 01 in byte 3 is used for the assignment to
PCD 1. The byte 4 is not used and is thus filled
with Hex 00 by the master.
PVA
In the high portion of the PVA is Hex 0000. In the
low portion of the PVA is Hex 0208 = 520 decimal.
The parameter number for the display of the of the
motor current is thus assigned to the PCD 1.
CTW and MRV
For an explanation of the control word and of the
main reference value see example 1.
PCD 1 to 4
Since PPO 2 is used, PCD1-4 must be transmitted
by the master (filled with zeros as the PCD-Write
are not defined).
MG.90.D1.02 – VLT is a registered Danfoss trademark
VLT ® 5000/5000 Flux/6000 HVAC/8000 AQUA PROFIBUS
VLT response telegram (PPO2)
The VLT might send back the following telegram to
the master:
PCV
PCD
Value (Hex)
7394
PCA
0100
Hex 4 corresponds to "transmit parameter value
0000
(array word)" in the RC portion of the PCA.
0208
Hex 394 = 916 decimal. The VLT repeats the para-
047F
meter number sent by the master (for handshake
2000
control).
0000
I N D
0000
The VLT repeats the subindex sent by the master
0000
(for handshake control).
0000
PVA (high word and low word)
The VLT repeats the parameter number sent by the
master (for handshake control).
STW and MAV
For an explanation of the status word and of the
main actual value see example 1.
PCD1
HEX F6 = 246 decimal. The conversion index for
parameter 520 is -2, i.e. the value must be divided
by 100. Thus, the present motor current is: 2.46 A
PCD 2 to PCD 4
Since the PCD in this example are not configured
yet, the VLT will fill the individual PCD with
Hex 0000.
of the VLT if parameter 971 is activated after the
parameter modification. This is not done in the
example, i.e. the configuration of the PCD data is
lost after switching the mains current off/on.
Byte
PCA 1 and 2
I N D 3 and 4
PVA 5 and 6
PVA 7 and 8
STW 9 and 10
MAV 11 and 12
PCD 1 13 and 14
PCD 2 15 and 16
PCD 3 17 and 18
PCD 4 19 and 20
Please note that modified parameters are
only saved permanently (protected against
the event of a mains failure) in the EEProm
Value (Hex)
4394
0100
0000
0208
0F07
2000
00F6
0000
0000
0000
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