Danfoss VLT 7000 Series, Руководство пользователя

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VLT® 7000 Booster
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Quick menu 20 Par. 703 SBW Destage delay
Par. 703 SBW Destage delay
(SBW DESTAG DELAY)
Value:
0 - 3000 sec.
✭
10 sec.
Function:
Immediate destaging of a fixed speed pump is not
desirable when a momentary pressure increase in the
system that exceeds the Staging bandwidth (SBW)
occur. Destaging is delayed by the length of time
programmed, and happens only when min. frequency
is reached. If the pressure decreases to within the SBW
before the timer has elapsed, the timer is reset.
Description of choice:
Set the SBW destage delay. A delay time of 10 seconds
(factory setting) is sufficient in most systems. When
encountering frequent staging, increase the delay time.
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Quick menu 21 Par. 704 SBW Stage delay
Par. 704 SBW Stage delay
(SBW STAGE DELAY)
Value:
0 - 3000 sec.
✭
10 sec.
Function:
Immediate staging of a fixed speed pump is not
desirable when a momentary pressure drop in the
system that exceeds the Staging bandwidth (SBW)
occur. Staging on is delayed by the length of time
programmed and happens only when the speed is at
max. frequency. If the pressure increases to within the
SBW before the timer has elapsed, the timer is reset.
Description of choice:
Set the SBW stage delay. A delay time of 10 seconds
(factory setting) is sufficient in most systems. When
encountering frequent staging, increase the delay.
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Quick menu 22 Par. 705 Override bandwidth
Par. 705 Override bandwidth
(OVERRIDE BANDW.%)
Value:
2 - 100% (100 = Off)
✭
100% = Off
Function:
When a large and quick change in the system demand
(such as a sudden water demand), the system pressure
rapidly changes and an immediate staging or destaging
of a fixed speed pump becomes necessary to match
the requirement. The Override bandwidth (OBW) is
programmed to override the staging/destaging timer
for immediate response. The Override bandwidth is a
percentage of the setpoint and defines the feedback
(pressure) at which the timers (set in parameters 703,
704) are overridden. For example, if the setpoint
is 5 bar and the override is set to 20%, the low
limit is 4 bar and the high limit 6 bar.
Description of choice:
The OBW must always be programmed to a higher
value than the staging bandwidth (SBW) set in
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