6.1 Preparations for starting up
DANGER
Rotating elements
Death or serious personal injury
‐
Before manual startup or changeover
to automatic control, make sure that no
persons are working on or near the
pump.
Before the first startup and after a long
standstill period, make sure the pump is
vented and filled with the pumped liquid.
In dry installations with cooling jacket, the
cooling jacket must always be filled with
the pumped liquid during operation.
6.2 Level of pumped liquid
An Ex motor without a cooling jacket (in-
stallation types S and ST) must be com-
pletely submerged during operation.
Install an additional level switch to ensure
that the pump is 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.
1
3
2
TM079307
Liquid levels
Pos.
Description
1
Installation S (Ex pumps)
2
Installation S (standard pumps)
3
Installation type C (standard and Ex pumps)
•
Installation types D and H:
During operation, the cooling jacket
must be filled with the pumped liquid to
ensure sufficient cooling. Before the
first startup and after long standstill pe-
riods, the air must be ventilated from
the cooling jacket through an air-vent
valve.
•
Installation type ST:
The liquid level must be at
least 900-1100 mm above the pump inlet.
6.2.1 Start and stop levels for auto-coupling
installations
The start and stop levels are specified during the
design stage. Always check that the start and stop
levels are functioning and possibly alter them when
starting up the pump to ensure proper operation.
Stop levels
Set the stop level according to the figure
below.
28
English (GB)
Summary of Contents for ST-55-520
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