Danfoss VLT 3500 HVAC, Руководство пользователя

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VLT
®
3500 HVAC
MG.35.B1.02 – VLT is a registered Danfoss trademark
Example 9:
In a ventilation system where there is no access to
VLT 3500 HVAC, external switching between hand
operation "Hand" and remote operation "Auto" on the
frequency converter is required.
A 3-point switch is used that allows a choice between
"Hand-Off-Auto". The "Hand" reference is a 0-10 V
signal on a potentiometer. When VLT 3500 HVAC runs
in the Auto mode, the frequency converter is control-
led using a 4-20 mA reference.
NB!: NB!:
NB!: NB!:
NB!:
Screen for control cables must be connected
as described in the chapter on EMC-correct
installation.
All settings are based on factory settings; however,
motor data settings (parameters 104, 105 and 107)
(or the Quick Set-up menu items 1, 2 and 3) are to be
adjusted to the motor connected.
1 = Activation of Hand Mode
2 = Activation of Auto Mode
3 = Stop
4 = Start Auto Mode
5 = Pulse Start Hand Mode
6 = Auto Mode reference, 4-20 mA
7 = Hand Mode reference, 0-10 V/1 K
Ω
The following must be programmed:
Function: Parameter no. Parameter value Data value no.
H-O-A position 003 EXT. HOA [2]
Activation of Hand 400 EXT. HOA HAND [5]
Activation of Auto 401 EXT. HOA AUTO [7]
Pulse Start Hand 405 LATCH ST. HAND [4]
Hand reference 420 VOLTAGE [0]
Auto reference 413 4-20 mA [2]
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2.7 Installation examples