Embraco Sliding unit Series, Руководство по установке

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General Hints
High pressure limiters and pressure cut outs with type
approval according to EN 12263 feature a double
bellows design.
Should the inner bellows leak, then the larger surface
area of the outer bellows creates a larger force and
causes the pressostat to a pre-empted cut out. This
represents a fail-safe function.
Electrical contacts
PS1 / PS2 pressure controls are equipped with high
rated double snap action contacts for shatter-free and
reliable operation. All contacts are designed as Single
Pole
Double Throw (SPDT) contacts. Dual
Pressostats PS2 come with two independently
actuated SPDT contacts.
Switch Points
The set points are adjustable with internal adjustment
spindles. The range spindle allows presetting the
upper switch point together with the lower switch point .
The differential spindle is used to preset the lower
switch point . The dependency between upper and
lower set point is as follows:
lower set point = upper set point
– differential
Parts with manual reset feature a fixed differential.
Manual reset is possible as soon as pressure falls
below / rises above this fixed differential (see selection
table).
Contact function
Contacts on Single Pressostats PS1 are labeled1-2-
4, contacts on Dual Pressostats are labeled 11-12-14
on the left side and 21-22
– 24 on the right side.
„1“, „11“, „21“ refer to the common pole.
„2“, „12“, „22“ refer to the lowe setpoint and
„4“, „14“, „24“ refer to the upper setpoint common. This
is true for all functions: low pressure controls, high
pressure controls, manual or automatic reset types.
Automatic reset
On pressure rise above the upper setpoint, contacts
1-2 (11-12; 21-22) open and contacts 1-4 (11-
14, 21-24) close. On decreasing pressure below
lower setpoint contacts 1-4 (11-14; 21-24) open and
contacts 1-2 (11-12; 21-22) close.
Manual reset low pressure
On decreasing pressure below the lower setpoint,
contacts 1-4 open, contacts 1-2 close and latch. On
pressure rise above fixed differential per Selection
Table and after pressing the manual reset button,
contacts 1-2 will open and contacts 1-4 will close
again.
Manual reset high pressure
On increasing pressure above the upper setpoint,
contacts 1-2 open, contacts 1-4 close and latch. On
falling
pressure below fixed differential per
Selection Table and after pressing the manual reset
button, contacts 1-4 will open and contacts 1-2 will
close again.
For operational safety, all PS1 / PS2 with manual
reset are designed as
trip-free controls, i.e. pressing
the manual reset button while the pressure has not
reached its reset threshold will not operate the
electrical contacts.
Installation and maintenance
A front access
manual toggle is
provided
for
checking out
control operation.
On low pressure
controls
this
toggle may be
used to override
the low pressure
signal during system evacuation, avoiding the
need to undo the electrical wiring for this purpose.
The standard mounting holes for mounting brackets
are equipped with a universal thread to fit both, M4 and
UNC 8-32 screws.
The
standard wholesale
package includes two
mounting screws and
a locking plate. Several hole
patterns for surface mounting are provided, see
physical dimensions.