Pipe Filling Function - Grundfos CRE Instrucciones De Instalación Y Operación

"Set minimum flow"
Set the minimum flow (Q ) in this display. This setting
min
determines at which flow rate the system is to change from
continuous operation at constant pressure to start-stop operation.
The setting range is 5 to 30 % of rated flow.
Factory setting
See section 10. Technical data.
"Diaphragm tank volume"
The stop function requires a diaphragm tank of a certain minimum
size. Set the size of the installed tank in this display.
In order to reduce the number of start-stops per hour or to reduce
the ∆H, install a larger tank.
Install the tank immediately after the pump. The precharge
pressure must be 0.7 x actual setpoint.
Recommended diaphragm tank size:
Rated flow rate
of pump CRE pump
3
[gpm (m /h)]
0-26
1s, 1, 3
(0 - 5.9)
27-105
5, 10, 15
(6.1 - 23.8)
106-176
20, 32
(24.2 - 40)
177-308
45
(40.2 - 70.0)
309-440
64, 90
(70.2 - 99.9)
441-750
120, 150
(100-170)
Factory setting
See section 10. Technical data.

7.18 "Pipe filling function"

Pump variant
CME
CRE, CRIE, CRNE, CRKE, SPKE, MTRE
This function is typically used in pressure-boosting applications
and ensures a smooth startup of systems with for instance empty
pipes.
Startup takes place in two phases. See fig. 73.
1. Filling phase.
The pipes are slowly filled with water. When the pressure
sensor of the system detects that the pipes have been filled,
phase two begins.
2. Pressure build-up phase.
The system pressure is increased until the setpoint is
reached. The pressure build-up takes place over a pressure
build-up time. If the setpoint is not reached within a given
time, a warning or an alarm can be given, and the pumps can
be stopped at the same time.
Pressure
Typical diaphragm
tank size
[gal (liters)]
2 (7.6)
Fig. 73 Filling and pressure build-up phases
Setting range
4.4 (16.7)
• "Filling speed".
Fixed speed of the pump during the filling phase.
14 (53.0)
• "filling pressure".
The pressure that the pump must reach before the maximum
34 (128.7)
filling time.
• "max. filling time".
62 (234.7)
The time in which the pump must reach the filling pressure.
• "Max. time reaction".
86 (325.5)
Reaction of the pump if the maximum filling time is exceeded:
– warning
– alarm (pump stops).
• "Pressure build-up time".
Ramp time from when the filling pressure is reached until the
setpoint must be reached.
"Pipe filling
function"
●
●
Factory setting
See section
1. Filling phase 2. Pressure build-up
(constant-curve phase
operation) (constant-pressure
operation)
"Setpoint"
Filling pressure
Actual value
Filling time Pressure
build-up
time
Maximum filling time
When you activate this function, the function always
starts when the pump has been in operating mode
"Stop" and is changed to "Normal".
10. Technical data.
Setpoint
ramp-up
Time
[sec]
51