VLT® 7000 Booster
Start and stop
functionality
■
Start and stop functionality
Two overall types of start/stop functions are provided
by the cascade controller option, one type quickly
stops all pumps while the other stages off the pumps in
a sequence, allowing for a controlled pressure stop.
Do not use these functions as emergency
stops. Some functions do not turn
off all pumps!
The Start and Stop functions are described in the
table below and are valid for all modes available. In
a sequenced stop, there is a one ramp-down time
delay between each destaging of the pumps.
Type
Terminal and parameter
Description
System stop and start via
LCP
STOP/OFF key AUTO/START key
The lead pump decelerates to a
stop and all constant speed pumps
are stopped at a time.
Start of lead pump via LCP
HAND/START key
Only the lead pump is running. If
more pumps are running, they are
destaged with a controlled stop.
System start and stop
Terminal 17 - parameter 301 - (SYSTEM
START)
At digital input low, the lead pump
decelerates to a stop, and then
provides sequenced stop for all
constant speed pumps.
Stop and start of lead-pump
only
Terminal 18 - parameter 302 - (START)
At digital input low, the lead pump
decelerates to a stop. The constant
speed pumps continue to operate
normally controlled by the cascade
controller in the VLT.
Fast system stop
Terminal 27 - parameter 304 - (COAST
INVERSE)
At digital input low, the constant
speed pumps stop immediately.
The lead pump coasts to a stop.
When only the lead pump is stopped, the cascade
controller will try to maintain the pressure in the system,
by staging and destaging the remaining pumps.
NB!:
Should the drive trip for any reason, the
cascade controller can continue operation
with the remaining pumps. Only at live zero
where Parameter 318 Live zero functionality is set
to (STOP) or (STOP AND TRIP) or at Warning 8 (DC
UNDERVOLTAGE), all pumps will stop.
It is also possible to stop every single pump in the
system manually e.g. for service. Please read below.
NB!:
Please note that par. 719 and 720 are
indexed parameters.
■
Quick Menu 34 Par. 719 Pump enable
Par. 719 Pump enable
(PUMP ENABLE)
Value:
0
1
✭
1
Function:
If a pump is to be removed from the system due to
repairs or service this can be done by disabling the
specific pump. The system will continue without any
interruption, and the pressure will be controlled as good
as possible by the remaining pumps. Disabling a pump
will lead to an immediate destaging of the pump, and
it will not be staged on until it is enabled again.
Please note, that the lead pump cannot be
disabled. It is not possible to disable pumps in
pump combination 1-4 (par. 701).
1: Enable
0: Disable
MG.70.A1.02 - VLT is a registered Danfoss trademark
107
Содержание VLT 7000 Series
Страница 13: ...VLT 7000 Booster Introduction to Booster Ordering form MG 70 A1 02 VLT is a registered Danfoss trademark 13...
Страница 22: ...VLT 7000 Booster Mechanical dimensions MG 70 A1 02 VLT is a registered Danfoss trademark 22...
Страница 30: ...VLT 7000 Booster MG 70 A1 02 VLT is a registered Danfoss trademark 30...