System Status And Operation; Start/Stop Conditions - Danfoss VLT Series Quick Manual

Quick Guide
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1.5.1 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:

1.5.2 Start/Stop Conditions

See 5-1* Digital Inputs.
Digital input commands
Start (SYSTEM START/STOP)
Lead Pump Start
Coast (EMERGENCY STOP)
External Interlock
Table 1.20 Commands Assigned to Digital Inputs
LCP keys
[Hand On]
[Off]
[Auto On]
Table 1.21 Function of Keys on LCP
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VLT HVAC Basic Drive Cascade Controller Quick Guide
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Variable speed pump (lead)
Ramps up (if stopped and there is a
demand)
Ramps up if SYSTEM START is active
Coast to stop
Coast to stop
Variable speed pump (lead)
Ramps up (if stopped by a normal stop
command) or stays in operation if already
running
Ramps down
Starts and stops according to commands via
terminals or serial bus cascade controller
only can work when drive in "Auto ON"
mode
®
MG18F402 - VLT is a registered Danfoss trademark
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.
Fixed speed pumps (lag)
Staging (if stopped and there is a demand)
Not affected
Cut out (correspond relays, terminal 27/29
and 42/45)
Cut out (built-in relays are de-energized)
Fixed speed pumps (lag)
Destaging (if running)
Destaging
Staging/Destaging