2.21.2. 25-0* System Settings
Parameters related to control principles and configuration of the system.
25-00 Cascade Controller
Option:
Function:
[0]
*
Disabled
[1]
Enabled
For operation of multiple devices (pump/fan) systems where
capacity is adapted to actual load by means of speed control
combined with on/off control of the devices. For simplicity only
pump systems are described.
Disabled
[0]: The Cascade Controller is not active. All built-in
relays assigned to pump motors in the cascade function will be
de-energized. If a variable speed pump is connected to the fre-
quency converter directly (not controlled by a built-in relay); this
pump/fan will be controlled as a single pump system.
Enabled
[1]: The Cascade Controller is active and will stage/
destage pumps according to load on the system.
25-02 Motor Start
Option:
Function:
[0]
*
[1]
Direct on Line
Soft starter
Motors are connected to the mains directly with a contactor or
with a soft starter. When the value of
Motor Start
, Par. 25-02,
is set to an option other than
Direct on Line
[0], then
Lead Pump
Alternation
, par. 25-50, is automatically set to the default of
Direct on Line
[0].
Direct on Line
[0]: Each fixed speed pump is connected to line
directly via a contactor.
Soft Starter
[1]: Each fixed speed pump is connected to line via
a soft starter.
25-04 Pump Cycling
Option:
Function:
[0]
*
Disabled
[1]
Enabled
To provide equal hours of operation with fixed speed pumps,
the pump use can be cycled. The selection of pump cycling is
either “first in – last out” or equal running hours for each pump.
Disabled
[0]: The fixed speed pumps will be connected in the
order 1 – 2 – 3 and disconnected in the order 3 – 2 – 1. (First
in – last out)
Enabled
[1]: The fixed speed pumps will be connected/discon-
nected to have equal running hours for each pump.
2. Parameter Description
VLT
®
AQUA Drive Programming Guide
228
MG.20.O2.02 - VLT
®
is a registered Danfoss trademark
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