1.1.1 System Status and Operation
Only when lead pump is working, the frequency converter
can go into sleep mode. When the Cascade Controller is
enabled, the operation status for each pump and the
Cascade Controller is displayed by
25-81, Pump Status
and
25-80, Cascade Status
on the LCP. Cascade Controller
information displayed includes:
•
Pumps Status, is a read out of the status for the
relays assigned to each pump. The display shows
pumps that are disabled, off, running on the
frequency converter or running on the mains/
motor starter.
•
Cascade Status, is a read out of the status for the
Cascade Controller. The display shows the
Cascade Controller is disabled, all pumps are
running off, fixed speed pumps are being
staged/de-staged and lead pump alternation is
occurring.
1.1.2 Start/Stop Conditions
See
5-1* Digital Inputs
.
Digital input commands
Variable speed pump (lead)
Fixed speed pumps (lag)
Start (SYSTEM START/STOP)
Ramps up (if stopped and there is a
demand)
Staging (if stopped and there is a demand)
Lead Pump Start
Ramps up if SYSTEM START is active
Not affected
Coast (EMERGENCY STOP)
Coast to stop
Cut out (correspond relays, terminal 27/29
and 42/45)
External Interlock
Coast to stop
Cut out (built-in relays are de-energized)
Table 1.1 Commands Assigned to Digital Inputs
LCP keys
Variable speed pump (lead)
Fixed speed pumps (lag)
[Hand On]
Ramps up (if stopped by a normal stop
command) or stays in operation if already
running
Destaging (if running)
[Off]
Ramps down
Destaging
[Auto On]
Starts and stops according to commands via
terminals or serial bus cascade controller
only can work when drive in "Auto ON"
mode
Staging/Destaging
Table 1.2 Function of Keys on LCP
1.1.3 Cascade Controller Parameter Detail
Parameter
Range
Default
Function
25-00 Cascade
Controller
*[0] Disabled
[1] Enabled
*[0] Disabled Enable/disable
the cascade
controller which
is used for
staging multiple
pumps.
25-04 Pump
Cycling
*[0] Disabled
[1] Enabled
*[0] Disabled Select the
method for
determining the
order of cutting
in/out the fixed
speed pumps.
Parameter
Range
Default
Function
25-05 Fixed
Lead Pump
[0] No
*[1] Yes
*[1] Yes
Select if the lead
pump is fixed
(Yes) or can be
cycled (No).
25-06 Number
of Pumps
2 - Expres-
sionlimit (5)
*2
Set the total
number of
pumps including
the variable
speed pump.
VLT® HVAC Basic Drive Casca...
VLT
®
HVAC Basic Drive Cascade Controller
2
MI18I302 - VLT
®
is a registered Danfoss trademark
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