26
It is important to note here that normally one unit will be in the standby position, all
others will be online or unoccupied. Therefore, toggling the state of a single transfer
switch will always toggle the transfer switches associated with two chain positions.
The NSU will recognize and automatically add new converters to the redundancy chain.
To add a converter to the redundancy chain, the form-c contacts must be connected, the
RS485 connection between the NSU and the converter must be established (or the
NSU-Converter Serial Link must be disabled), and the NSU must establish
communication with the switch module. Converters can only be added to the
redundancy chain using the technique described above. Once a converter has been
added to the redundancy chain a lapse in any of the above criteria will not eliminate the
converter from the redundancy chain.
Removing converters from the redundancy chain must be done deliberately either from
the front panel or by using remote commands. The control unit will not automatically
change a chain position to the unoccupied state. To eliminate a redundancy chain
position: place the NSU in the manual redundancy mode, change the position to
unoccupied “- -“ and press “Enter”. A message appears “Change Position nn to
Inactive? Select “Yes” to disconnect the switch and the converter. If nothing is done the
default is “No” and the switch and converter will remain active in the redundancy chain.
3.2.5 CONVERTER SETTINGS SUBSCREEN
The settings for each of the converters in the redundancy chain are accessible from a
subscreen of the Redundancy Chain Status screen. The polling process updates the
settings stored in the NSU for converters that have their NSU-Converter Serial Link
option enabled. The operator must enter settings stored in the NSU for converters that
have NSU-Converter Serial Link disabled.
•
To access a Converter Settings Subscreen from the Redundancy Chain Status
screen, press the left or right arrow key until cursor is just left of the desired chain
↑
01 RF:14500.125MHz IF:140MHz PRI:05
↓
ATT:30.0dB SLP:+2.4dB EQ:-3.6dB POL:VER
CHANGE POSITION xx TO INACTIVE?
→
NO YES