Danfoss VLT 6000 series, Manual

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VLT ® 6000 HVAC
11
MG.60.G2.02 - VLT is a registered Danfoss Trademark
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VLT 6000 Network Strategies
Network Inputs to the VL Network Inputs to the VL Network Inputs to the VL Network Inputs to the VL Network Inputs to the VLT 6000: T 6000: T 6000: T 6000: T 6000:
The following drive points might be controlled by
the FLN.
Speed Command: Speed Command:
Speed Command: Speed Command: Speed Command:
5 3 5 3
5 3 5 3
5 3 BUS REF BUS REF
BUS REF BUS REF
BUS REF – This is the speed reference
command. This is set as a percentage of the
drive’s reference range, determined by
VLT 6000 parameters 204, Minimum
Reference , and 205, Maximum Reference .
Setting point 53 to 0 gives the drive a
reference command equal to the value
stored in parameter 204. Setting point 53
to 16384 gives the drive a reference
command equal to the value stored in
parameter 205.Intermediate values for point
53 change the reference linearly between
these two values.
NOTE: NOTE:
NOTE: NOTE:
NOTE:
In general, any other reference signal is
added to the bus reference. Disable all other
drivereference inputs when using a bus reference to
control drive speed.
Example 1: Example 1: Example 1: Example 1: Example 1: In a pumping application, the
minimum frequency (point 38 or parameter 201) is
set to 18 Hz, and the maximum frequency (point
39 or parameter 202) is set to 60 Hz. You want to
command the drive’s speed with a 0 – 100%
signal, where 0% commands 18 Hz and 100%
commands 60 Hz. To unbundle the bus reference
(point 53) for commanding in percent:
1. Set minimum reference (point 50 or
parameter 204) to 18 Hz, the minimum
frequency.
2. Set maximum reference (point 51 or
parameter 205) to 60 Hz, the maximum
frequency.
3. Intercept = 0 (since the minimum reference
value is 0).
4. Slope can be calculated as follows:
The VLT 6000 drive has its own internal PID closed
loop controller. This can be turned on or off,
depending on the requirements of the control
strategy. A brief summary of possibilities follows. This
is meant to illustrate possibilities rather than be all-
inclusive. An actual application may combine
features from a more than one of these strategies.
Strategy One
FLN Function FLN Function FLN Function FLN Function FLN Function – Monitor drive operation
VL VL
VL VL
VLT 6000 Contr T 6000 Contr
T 6000 Contr T 6000 Contr
T 6000 Control ol
ol ol
ol – From a conventional,
hardwired system
VL VL VL VL VLT 6000 Mode T 6000 Mode T 6000 Mode T 6000 Mode T 6000 Mode – Open Loop
The VLT 6000 follows hard-wired run/stop
signals. An external, hard-wired PID controller
provides the drive with a speed reference signal.
The FLN monitors the operation of the drive
without control function.
Network Inputs to the VL Network Inputs to the VL
Network Inputs to the VL Network Inputs to the VL Network Inputs to the VLT 6000:
T 6000:
T 6000: T 6000: T 6000: Because the
FLN is simply monitoring the operation of the drive, it
provides no inputs.
Network Outputs fr Network Outputs fr Network Outputs fr Network Outputs fr Network Outputs from the VL om the VL om the VL om the VL om the VLT 6000: T 6000: T 6000: T 6000: T 6000: The
following points are monitored by the FLN to indicate
system status. This list could be expanded or
shortened, depending on the requirements of the
system.
03 FREQ OUTPUT
08 POWER
10 KWH
23 STOP.RUN
92 OK.FAULT
Strategy Two
FLN Function FLN Function FLN Function FLN Function FLN Function – Control all aspects of drive
operation
VL VL VL VL VLT 6000 Contr T 6000 Contr T 6000 Contr T 6000 Contr T 6000 Control ol ol ol ol – From FLN
VL VL
VL VL VLT 6000 Mode
T 6000 Mode
T 6000 Mode T 6000 Mode T 6000 Mode – Open Loop
The VLT 6000 follows run/stop and speed reference
signals from the FLN. The FLN receives the
feedback signal from the controlled system,
compares this to a setpoint value, and uses its own
PID control loop to determine the required drive
speed.