ABB ACH 400, User Manual

Page: 27 / 44

Chapter 4 – Programming
ACS/ACH 400 Direct N2 Bus Interface 4-5
2 = CONSTANT SPEED 7
Drive keeps on running
The drive will show the
OEM
fault on the panel
and will continue running at the constant speed
set by parameter 1208 CONST SPEED 7. The
drive will also go to the Off-Line state on the
N2 Bus. To restart the drive, communication
must be restored and the fault must be cleared.
3 = LAST SPEED
Drive keeps on running
The drive will show the
OEM
fault on the panel
and will continue running at the last reference
speed. The drive will also go to the Off-Line
state on the N2 Bus. To restart the drive,
communication must be restored and the fault
must be cleared.
WARNING! The changes to parameters 2 - 4
will take effect only when the drive is
powered up. When these parameters are
changed, the power must be disconnected
from the drive until the drive panel is blank.
5 Good Message Counter
This counter calculates the received good
messages from the Metasys system. If this
counter is advancing, the ACS/ACH 400 is on-
line on the N2 Bus and the Metasys is
communicating to the drive.
6 Bad Message Counter
This counter counts the communication errors
on the N2 Bus. If there are no errors, no
duplicate stations, and no noise on the link, this
counter will not advance. This counter will also
advance when the baud-rate is incorrect.
The Bad Message counter also counts all the
replies with an error code. These errors could
be caused by an incorrect message, by a
command for a non-existing point, or by an
incorrect command type for a point.
7 Framing Error Counter
This counter counts the framing errors on the
N2 Bus. This counter will advance when the
baud-rate is incorrect or there is noise on the
line.
8 Overrun Counter
This counter counts the overrun errors on the
N2 Bus.