12. Technical data
12.1 Operating conditions
12.1.1 pH value
All pumps can be used for pumping liquids with a pH value between
4 and 10.
12.1.2 Liquid temperature
The allowed temperature is 32-104 °F (0-40 °C).
In special situations, if the motor is not fully loaded, the
temperature of the pumped liquid may be higher.
If necessary, contact the nearest Grundfos company or
service workshop.
Explosion-proof pumps must never pump liquids with a
FM
temperature higher than 104 °F (40 °C).
12.1.3 Ambient temperature
The allowed temperature is 32-104 °F (0-40 °C).
For explosion-proof pumps, the ambient temperature on
FM
the installation site must be between 32 and 104 °F (0 and
40 °C).
12.1.4 Specific weight and viscosity of the pumped liquid
Specific weight: 8.34 lb/gal.
2
Kinematic viscosity: 1 cSt (1 mm
When pumping liquids with a specific weight and/or a
kinematic viscosity higher than the values stated above,
use motors with correspondingly higher outputs.
12.1.5 Flow velocity
Keep a minimum flow velocity to avoid sedimentations in the pipe
network.
Recommended velocities:
Vertical pipes:
2.3 ft/s (0.7 m/s)
Horizontal pipes: 3.3 ft/s (1.0 m/s)
12.1.6 Installation depth
The maximum submersion depth is 66 ft (20 m).
12.1.7 Level of pumped liquid
An Ex motor without cooling jacket, (installation types S
FM
and ST) must be completely submerged during operation.
Install an additional level switch to ensure that the pump is
FM
stopped in case the stop level switch is not operating.
To avoid air being sucked into the pump and to ensure adequate
cooling of the motor during operation, make sure to meet the
following minimum requirements:
•
Installation type S: For continuous operation, S1, the pump
must always be covered by the pumped liquid to the top of the
motor. See fig. Liquid levels.
•
Installation type C: The pump housing must always be
covered by the pumped liquid.
For installation type C, the vent valve must always be
open, also during operation.
/s).
Liquid levels
Pos.
Description
S
Ex pumps, installation type S
C
Installation type C
•
Installation types D and H:
During operation, the cooling jacket must be filled with
pumped liquid to ensure sufficient cooling. Before the first
FM
startup and after long standstill periods, the air must be
evacuated from the cooling jacket through an air-vent
valve.
•
Installation type ST: The liquid level must be at least 35.4 -
43.3 in (900-1100 mm) above the pump inlet. See fig. Column
pipe installation, type ST.
12.1.8 Operating mode
The pumps are designed for continuous operation with the
maximum number of starts per hour stated in the table below.
S pump, range
72
74 and 78
12.1.9 Enclosure class
IEC IP68.
S
C
Starts per hour
15
10
31