Operating Conditions - Grundfos SL1 Instrucciones De Instalación Y Funcionamiento

2.5 Operating conditions

The Grundfos SL1 and SLV pumps are suitable for the following
operating situations:
• S1 operation (continuous operation), the pump must always
be covered by the pumped liquid to the top of the motor.
See fig. 2.
• S3 operation (intermittent operation), the pump must always
be covered by the pumped liquid up to the top of the cable
entry. See fig. 2.
For further information about S1 and S3 operation, see section
9.2 Operating modes.
Fig. 2 Stop levels
pH value
SL1 and SLV pumps in permanent installations can be used for
pumping liquids with a pH value between 4 and 10.
Liquid temperature
32 °F to +104 °F (0 °C to + 40 °C).
For short periods (maximum 3 minutes) a temperature of up to
+140 °F (+60 °C) is permissible (non-FM versions only).
Warning
FM
Explosion-proof pumps must never pump liquids
of a temperature higher than +104 °F (+40 °C).
Ambient temperature
Warning
FM
For explosion-proof pumps, the ambient
temperature on the installation site must be in
the range from -4 °F to +104 °F (-20 °C to +40 °C).
For explosion-proof pumps with WIO sensor, the
ambient temperature at the installation site must
be in the range from 32 °F to +104 °F
(0 °C to +40 °C).
For non-explosion proof pumps, the ambient temperature may
exceed +104 °F (+40 °C) for a short period (max. 3 minutes).
S1 operation
S3 operation
Density and viscosity of pumped liquid
When pumping liquids with a density and/or a kinematic viscosity
higher than that of water, use motors with correspondingly higher
outputs.
Pumping liquids with high content of solids, fibres etc.
Note
This procedure applies only to vortex impellers.
In very tough applications, and in applications with high content of
solids, fibres, etc. it is advisable to rotate the impeller backwards
a few seconds, before or after each pump cycle.
Do not rotate the impeller in single-channel
Caution
impeller pumps backwards.
Flow velocity
It is advisable to keep a minimum flow velocity to avoid
sedimentations in the piping system. Recommended flow
velocities:
- in vertical pipes: 2.3 ft/s (0.7 m/s)
- in horizontal pipes: 3.3 ft/s (1.0 m/s)
Installation depth
Maximum 65 ft (20 m) below liquid level.
Maximum solids size
From 2" to 4" (50 to 100 mm), depending on pump size.
Operating mode
Maximum 30 starts per hour.
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