Danfoss VLT 5000 Series, Руководство по эксплуатации

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VLT® 5000/ 5000 FLUX/ 6000 HVAC/
8000 AQUA PROFIBUS
■
SYNC and FREEZE
The control commands SYNC/UNSYNC
(SYNCHRONIZE/CANCEL SYNCHRONIZATION)
and FREEZE/UNFREEZE are broadcast functions.
SYNC/UNSYNC is used to transmit synchronized
control commands and/or speed reference values
to all connected slaves. FREEZE/UNFREEZE
is used to freeze the status actual value in the
slaves in order to receive a synchronized actual
value from all connected slaves.
The SYNC and FREEZE commands refer to the
PCD and PCV portions of the PPO.
■
SYNC/UNSYNC
By using SYNC/UNSYNC, simultaneous responses of
several slaves can be generated, e.g. synchronized
start, stop, or change of the speed. In the event of a
SYNC command, the current Control word and the
speed reference value are frozen. Incoming process
data are saved, but are only applied when a new SYNC
command or an UNSYNC command is made.
The following example shows the speed reference
value sent by the master in the left column and the
respective effective speed reference value for the three
slaves in the three columns to the right.
Current speed reference value slave
From DP master to address: VLT
Address 3 VLT
Address 4 VLT
Address 5
1. Speed reference value = 50% to address 3
⇒
50% 0 % 0 %
2. Speed reference value = 50% to address 4 50%
⇒
50% 0 %
3. Speed reference value = 50% to address 5 50% 50%
⇒
50%
4. SYNC command to all addresses
⇒
50%
⇒
50%
⇒
50%
5. Speed reference value = 75% to address 3
⇒
50% 50% 50%
6. Speed reference value = 75% to address 4 50%
⇒
50% 50%
7. Speed reference value = 75% to address 5 50% 50%
⇒
50%
8. SYNC command to all addresses
⇒
75 %
⇒
75 %
⇒
75 %
9. Speed reference value = 100% to address 3
⇒
75 % 75 % 75 %
10. Speed reference value = 50% to address 4 75 %
⇒
75 % 75 %
11. Speed reference value = 25% to address 5 75 % 75 %
⇒
75 %
12. UNSYNC command to all addresses
⇒
100 %
⇒
50 %
⇒
25 %
13. Speed reference = 0% to address 3
⇒
0 % 50 % 25 %
14. Speed reference = 0% to address 4 0 %
⇒
0 % 25 %
15. Speed reference = 0% to address 5 0 % 0 %
⇒
0 %
■
FREEZE/UNFREEZE
By using FREEZE/UNFREEZE, simultaneous reading of
process data, e.g. output current, by several slaves
can be brought about. At a FREEZE command, the
actual current values are frozen. When instructed, the
slave will send back the value in effect at the time
the FREEZE command was issued. The respective
values are updated when a new FREEZE command
or an UNFREEZE command is issued.
The following example shows the current values read
by the master in the left column and the respective
effective value of the output current for the three
slaves in the three columns to the right.
Actual output current slave
VLT
VLT VLT
DP master reads address: Address 3 Address 4 Address 5
1. Address 3 output current = 2 A
⇐
2 A 3 A 4 A
2. Address 4 output current = 5 A 2 A
⇐
5 A 2 A
3. Address 5 output current = 3 A 3 A 2 A
⇐
3 A
4. FREEZE command to all
addresses
⇒
1 A
⇒
3 A
⇒
3 A
5. Address 3 output current = 1 A
⇐
4 A 2 A 5 A
6. Address 4 output current = 3 A 2 A
⇐
2 A 2 A
7. Address 5 output current = 3 A 3 A 1 A
⇐
2 A
8. UNFREEZE command to all
addresses
⇒
2A
⇒
3 A
⇒
4 A
Readout same as for 1, 2 and 3
MG.90.G1.02 - VLT is a registered Danfoss trademark
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