4.3. Parameter Descriptions
4.3.1. Parameter Set-up
Group
Title
Function
0-
Operation and Display Parameters used to program the fundamental functions of the adjustable frequency
drive and the LCP including: selection of language; selection of which variables are
displayed at each position in the display (e.g., static duct pressure or condenser
water return temperature can be displayed with the setpoint in small digits in the top
row and feedback in large digits in the center of the display); enabling/disabling of
the LCP keys/buttons; passwords for the LCP; upload and download of commissioned
parameters to/from the LCP and setting the built-in clock.
1-
Load / Motor
Parameters used to configure the adjustable frequency drive for the specific appli-
cation and motor including: open-loop or closed-loop operation; type of application
such as compressor, fan or centrifugal pump; motor nameplate data; auto-tuning of
the drive to the motor for optimum performance; flying start (typically used for fan
applications) and motor thermal protection.
2-
Brakes
Parameters used to configure braking functions of the adjustable frequency drive,
which, although not common in many HVAC applications, can be useful on special
fan applications. Parameters including: DC braking; dymamic/resistor braking and
over voltage control (which provides automatic adjustment of the deceleration rate
(auto-ramping) to avoid tripping when decelerating large inertia fans)
3-
Reference/Ramps
Parameters used to program the minimum and maximum reference limits of speed
(RPM/Hz) in open-loop or in actual units when operating in closed-loop); digital/
preset references; jog speed; definition of the source of each reference (e.g., which
analog input the reference signal is connected to); ramp-up and ramp-down times
and digital potentiometer settings.
4-
Limits/Warnings
Parameters used to program limits and warnings of operation including: allowable
motor direction; minimum and maximum motor speeds (e.g., in pump applications
it is typical to program a minimum speed to approx 30-40% to ensure pump seals
are adequately lubricated at all times, avoid cavitation and ensure adequate head is
produced at all times to create flow); torque and current limits to protect the pump,
fan or compressor driven by the motor; warnings for low/high current, speed, ref-
erence, and feedback; missing motor phase protection; speed bypass frequencies
including semi-automatic set-up of these frequencies (e.g., to avoid resonance con-
ditions on cooling towers and other fans).
5-
Digital In / Out
Parameters used to program the functions of all digital inputs, digital outputs, relay
outputs, pulse inputs and pulse outputs for terminals on the control card and all
option cards.
6-
Analog In / Out
Parameters used to program the functions associated with all analog inputs and an-
alog outputs for the terminals on the control card and General Purpose I/O option
(MCB108) (note: NOT Analog I/O option MCB109, see parameter group 26-00) in-
cluding: analog input live zero timeout function (which for example can be used to
command a cooling tower fan to operate at full speed if the condenser water return
sensor fails); scaling of the analog input signals (for example, to match the analog
input to the mA and pressure range of a static duct pressure sensor); filter time
constant to filter out electrical noise on the analog signal which can sometimes occur
when long cables are installed; function and scaling of the analog outputs (for ex-
ample, to provide an analog output representing motor current or kW to an analog
input of a DDC controller) and to configure the analog outputs to be controlled by
the BMS via a high level interface (HLI) (e.g., to control a chilled water valve) in-
cluding ability to define a default value of these outputs in the event of the HLI failing.
8-
Communication and
Options
Parameters used for configuring and monitoring functions associated with the serial
communications / high level interface to the adjustable frequency drive.
9-
Profibus
Parameters only applicable when a Profibus option is installed.
10-
CAN Ser. Com. Bus
Parameters only applicable when a DeviceNet option is installed.
11-
LonWorks
Parameters only applicable when a Lonworks option is installed.
13-
Smart Logic Controller Parameters used to configure the built in smart logic controller (SLC), which can be
used for simple functions such as comparators (e.g., if running above xHz, activate
output relay), timers (e.g., when a start signal is applied, first activate output relay
to open supply air damper and wait x seconds before ramping up) or a more complex
sequence of user defined actions executed by the SLC when the associated user
defined event is evaluated as TRUE by the SLC. (For example, initiate an economizer
mode in a simple AHU cooling application control scheme where there is no BMS. For
such an application, the SLC can monitor the outside air relative humidity, and if it
is below a defined value, the supply air temperature setpoint could be automatically
increased. With the adjustable frequency drive monitoring the outside air relative
humidity and supply air temperature via it’s analog inputs and controlling the chilled
water valve via one of the extended PI(D) loops and an analog output, it would then
modulate that valve to maintain a higher supply air temperature). The SLC can often
replace the need for other external control equipment.
4.2: Parameter Groups
4. How to Program
VLT
®
HVAC DRIVE High Power
Instruction Manual
82
MG.11.F1.22 - VLT
®
is a registered Danfoss trademark.
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