Xylem LOWARA e-SVE - Example: Ramp Settings; Example: Effective Required Value

en – Original instructions
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6.6.2 Example: Ramp Settings
The illustration shows the ramp settings.
No.
Description
1
P01 (Required Value)
2
P37 (Adjustment hysteresis) as a % of P36 (Adjustment window)
3
P36 (Adjustment window) as a % of P01 (Required Value)
4
P35 (Minimum speed - Duration)
5
P27 (Minimum speed)
6
→ Actual Head
7
→ Actual Speed
RA
→ P32 (Acceleration ramp at startup)
RB
→ P32 (Deceleration ramp at shutdown)
R1
→ P28 (Ramp 1) - Fast ramp speed increase
R2
→ P29 (Ramp 2) - Fast ramp speed decrease
R3
→ P30 (Ramp 3) - Slow ramp speed increase
R4
→ P31 (Ramp 4) - Slow ramp speed decrease
For further information on the adjustment of the ramps, see Par. 6.5.3.
6.6.3 Example: Effective Required Value
Pumps activation in cascade modes:
1. Lead pump reaches its P60 (Enable Speed).
2. Actual value falls to the cut in-value of the 1st assist pump.
The 1st assist pump switches on automatically. (Cut-in value = P01 (Required Value) - P59
(Actual Value Decrease))
3. A new required value, P02 (Effective Required Value) is calculated after the start up.
Calculation of Effective Required Value in Cascade Serial (MSE):
K = number of active pumps
Pr = pump priority
P02 (Actual Required Value) = P01 (Required Value) + (K – 1) * P58 (Actual Value Increase) –
(Pr – 1) * P59 (Actual Value Decrease)
Calculation of Effective Required Value in Cascade Synchronous (MSY):
K = number of active pumps (K ≥ Pr)
P02 (Actual Required Value) = P01 (Required Value) + (K – 1) * (P58 – P59)
H [bar]
t [s]