Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

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•
RELAY 1 (R1) and RELAY 2 (R2) are the built-in
relays in the Adjustable frequency drive.
•
When all relays are de-energized, the first built-in
relay to be energized will cut in the contactor
corresponding to the pump controlled by the
relay. For example, RELAY 1 cuts in contactor K1,
which becomes the lead pump.
•
K1 blocks for K2 via the mechanical interlock
preventing line power from being connected to
the output of the Adjustable frequency drive (via
K1).
•
Auxiliary break contact on K1 prevents K3 from
cutting in.
•
RELAY 2 controls contactor K4 for on/off control
of the fixed speed pump.
•
At alternation, both relays de-energize, and
RELAY 2 will be energized as the first relay.
Application Examples
VLT
®
HVAC Drive Design Guide
MG11BB22 - VLT
®
is a registered Danfoss trademark 6-7
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