Control Unit - Honeywell SmartVFD HVAC MR4 User Manual

C
ONTROL UNIT
6. C
ONTROL UNIT
The control unit of the drive consists of the control board and additional boards (option boards)
connected to the slot connectors of the control board.
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When delivered from the factory, the control unit of the drive contains the standard controlling
interface - the control terminals of the control board and the relay board - unless otherwise spe-
cifically ordered. On the next pages you will find the arrangement of the control I/O and the re-
lay terminals, the general wiring diagram and the control signal descriptions.
The control board can be powered externally (+24VDC, ±10%) by connecting the external pow-
er source to terminal #30, see page 52. This voltage is sufficient for parameter setting and for
keeping the control unit active. Note however that the measurements of the main circuit (e.g.
DC-link voltage, unit temperature) are not available when the mains is not connected.
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2
3
Figure 48. Location of control unit components
Locations of essential control unit components:
1 = Control terminals of the control board
2 = Terminals of relay board; NOTE: There are
two different compilations of relay boards
available. See section 6.1.
3 = Optional boards
4 = Disconnecting jumper for digital inputs, see
chapter 6.1.2.2
Honeywell
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