1 operation and monitoring, 2 limits of operation – Xylem Z8 ZR8 Z10 ZR10 Z12 ZR12 User Manual
Page 33
Installation, Operating and Maintenance Instruction
page
33
Motors which are only suitable for rotation in one
direction should not be allowed to run in reverse
for long. Pumps with single stage alternating
current motors will certainly run in the proper
direction if they are connected properly.
During the pump test it is necessary to keep the
plant under constant observation and to check the
current consumption and discharge. For new wells
or bore holes with unknown yield we recommend
checking the fall in water level as well as the sand
content of the water during the first period of
operations. Excess sand content (more than 50
g/m
3
) can lead very quickly to wear and reduced
output of the unit.
After insulation values have been measured again
after a few hours of operation the plant can be
operated automatically. To obtain comparable
values for winding resistance: Allow the motor to
cool for at least one hour before measuring.
Restarting
Each time operations are restarted proceed as in initial
operations. However, it is unnecessary to check the
insulation values, the direction of rotation or to
measure winding resistance.
6.1 Operation and Monitoring
Regular monitoring and maintenance will extend
the life of your pump or system.
You must observe the area of application given in
the Confirmation of Order.
Do not exceed the output given on the motor
rating plate.
Avoid dry running, running against closed
discharge valves.
Pay attention to the permitted number of starts.
6.2 Limits of Operation
The operating limits of the pump / unit regarding
pressure, temperature, performance and speed
are shown in the data sheet and / or order
confirmation and must be observed under any
circumstances!
Do not exceed the output given on the motor
name plate.
6.2.1 Flow min. / max.
If no other data are given in the curves or data sheets,
the following is valid:
Pump Size
Recommended minimum flow
for continuous operation [m
3
/h]
50 Hz
60 Hz
Z8-ZR855… 10
12
Z8-ZR875… 15
18
Z8-ZR895… 22
27
Z8-ZR8125… 30
36
Z10-ZR10150… 40
50
Z10-ZR10200… 60
80
Z10-ZR10275… 80
100
Z12-ZR12340… 150
180
Z12-ZR12420… 200
-
Pump Size
Maximum flow [m
3
/h]
for vertical and horizontal
installation
50 Hz
60 Hz
Z8-ZR855… 75
90
Z8-ZR875… 105
125
Z8-ZR895… 135
160
Z8-ZR8125… 170
200
Z10-ZR10150… 200
240
Z10-ZR10200… 250
280
Z10-ZR10275… 320
360
Z12-ZR12340… 400
400
Z12-ZR12420… 520
-
Values are valid under the requirement NPSH
Plant
>
(NPSH
Pump
+ 0,5 m)
6.2.2 Minimum depth of coverage
Pump Size
U
min
mm
…refers to a
velocity of
water of max.
…m/s in the
case space
between the
pump and well
casing.
Z8-ZR855…
1000
4,2
Z8-ZR875…
Z8-ZR895…
Z8-ZR8125…
Z10-ZR10150… 1600
4,5
Z10-ZR10200…
2900
Z10-ZR10275…
Z12-ZR12340…
2900
6,8
Z12-ZR12420…
6.2.3 Permitted number of starts
With electric motors, the permitted number of starts is
given in the attached motor operating instructions.
If there are not specified values for the operating
cycles in the motor instruction manual, then the values
of diagram 1 are valid.
1,0
10,0
100,0
1
10
100
1000
Motor power [kW]
m
a
x.
p
e
rm
.
st
ar
ts
/h
Diagram 1
If two different figures are given, the lower figure is
valid.