Control Unit - Vacon NX_ 0003 5 User Manual

66 • vacon
6.2

Control unit

The control unit of the AC drive consists roughly of the control board and additional boards (see Figure
6-23 and Figure 6-24) connected to the five slot connectors (A to E) of the control board. The control board
is connected to the power unit through a D-connector (1) or fibre optic cables (FR9).
Figure 6-23. NX control board
Usually, when the AC drive is delivered from the factory, the control unit includes at least the standard
compilation of two basic boards (I/O board and relay board) which are normally installed in slots A and B.
On the next pages you will find the arrangement of the control I/O and the relay terminals of the two basic
boards, the general wiring diagram and the control signal descriptions. The I/O boards mounted at the
factory are indicated in the type code. For more information on the option boards, see Vacon NX option
board manual (ud741).
The control board can be powered externally (+24V, ±10%) by connecting the external power source to
either of the bidirectional terminala #6 or #12, see page 69. This voltage is sufficient for parameter setting
and for keeping the fieldbus active. Note however that the analogue inputs and outputs as well as the
measurements of the main circuit (e.g. DC-link voltage, unit temperature) are not available when the
mains is not connected (with the exception of frame size FR9 and bigger).
Note! If the 24V inputs of several AC drives are parallelly connected we recommend to use a diode in
terminal #6 (or #12) in order to avoid the current to flow in opposite direction. This might damage the
control board. See picture below.
6
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
+ - + - +
#6 #7 #6 #7 #6
CABLING AND CONNECTIONS
A
Figure 6-24. Basic and option board connections
on the control board
External
+24V
- + -
#7 #6 #7
nk6_17
E
D
C
B