ABB ACA 6 Series, Hardware Manual

Page: 77 / 102

Chapter 3 – Electrical Installation
ACA 6xx Sections and ACS/ACC 6x7 (132 to 3000 kW) Frequency Converters 3-35
• one Control Panel is chained to many drive units
RS-485 Termination
Settings
When the Control Panel CDP 312 is connected to one NAMC-21/22
board only, the RS-485 line must be terminated on the NAMC-21/22
board by jumpers X5 as follows:
If CDP 312 is connected to several NAMC 21/22 boards (RS-485 panel
bus), the first and the last NAMC 21/22 board must be terminated. The
intermediate boards must not be terminated.
X3
X2
X1
X1
CDP 312
NDPI-21
X4
X3
X4
X3
NAMC-21/-22
X4
X3
X4
X3
X4
X3
[N-1]
[N]
[3]
NAMC-21/-22
[2]
[1]
NAMC-21/-22
NAMC-21/-22
NAMC-21/-22
The CDP 312 Control Panel can be
connected (through NDPI-21 or
directly) to the NAMC-21/22 board to
the 6-pin modular connector X3. The
modular connectors on the NIOC
board are
not intended for the Control
Panel.
The maximum cable length between
CDP 312 (or NDPI-21) and NIOC-01 or
NAMC-xx is 10 metres. In the
presence of high-level radiofrequency
disturbances, the length should be
limited to 3 metres.
The maximum total length of the panel
bus is 30 metres. With Panel Bus
Connection Interface Module NBCI-01
the maximum panel bus length can be
extended to 1200 metres (refer to
NBCI-0x Module Installation and Start-
up Guide
)
RS-485 panel bus
Control Panel cable
Max. 31 pieces
Terminated
Terminated
Not terminated
Not terminated
Not terminated
Fixed
termination
No termination
Terminated
Not terminated