2.2.4 Override/Override Release Commands
and Time Out, 8-04 (Setting [20], N2
Override release)
The way the overridden points are released is very important
to the way the drive will behave during the override release
time out or for release commands issued by the N2 master.
This is due to the fact that the active setup can be changed to
a different setup. If one would release the active setup before
the values that have been overridden in that setup, the
backup values would then be restored to the wrong setup,
leaving the overridden values in the old setup unchanged.
The release after override time out:
During an override release time-out, all points which are
overridden, will be released in the order, which they are
specified in Appendix POINTMAP:
1.
Release Analog Outputs from point address (NPA) 0
to 255.
2.
Release Binary Outputs from point address (NPA) 0
to 255.
3.
Release Internal Floating Points from point address
(NPA) 0 to 255.
4.
Release Internal Integer Points from point address
(NPA) 0 to 255.
5.
Release Internal Byte points from point address
(NPA) 0 to 255.
2.2.5 Change of State (COS)/POLLING
A change of state occurs when a new command has been
issued for the drive. This command can be issued through the
bus or through a drive related status change or command. The
master can issue a series of poll commands to the network
devices to get an update on any status changes from the time
of the last polling. When polling a frequency converter for the
first time after a network has been powered up after an F
command has been issued, a 0/4 poll command must be
issued.
2.2.6 Handling of Poll Message Commands
The Identity Command will cause the drive to report all AI, AO,
BI and BO points, which are available when the next Poll (0/4)
is received. The drive also supports COS for AI and BI point
types. The drive is limited to responding with up to 200 ASCII
characters, so multiple messages may need to be sent before
all available points have been reported.
Upon receiving the Poll (0/4), the frequency converter will
begin exporting the requested information. The frequency
converter will continue to export new information upon
receiving the 0/5 Poll until it has sent all requested informa-
tion. Then it will respond to a new 0/5 Poll with an ACK
response to indicate all information has been transmitted and
complete the Poll sequence receiving a 0/4 Poll before
sending the ACK response will cause the frequency converter
to re-transmit its latest response.
The drawing below illustrates the AI COS handling.
Instructions
VLT
®
Metasys
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MG.11.G2.02 - VLT
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