89750147 Crouzet USA, 89750147 Datasheet - Page 271

• Manufacturer Part Number: 89750147
• Description: STAINLESS SLEEVE-MILL TEMP PRB
• Manufacturer: Crouzet USA

Specifications of 89750147

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Our timers are pieces of automatic control equipment which, during a
cycle, are intended to operate a series of contacts in a preset order
following a program.
The cycle may be single (non-repetitive), repetitive, or step by step.
Though often decried, timers will greatly simplify automatic control
systems and allow much other hardware to be dispensed with.
They consist of:
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➜ Program storage mediums
Max space 180°
➜ Program representation
The positions and sequence of the commands in the program will be fully
defined by a diagram.
➜ Diagram plotting
By convention, the lower line represents the rest position and the upper
the working position. The heavy lines mean that the contact is closed.
The total cycle duration is represented in degrees for the cams.
➜ Importante note
Only the theoretical electrical (or pneumatic) values will be used for
plotting the diagrams. The equivalent mechanical values are peculiar to
the individual unit and are calculated when setting up the program or
cutting the cam contour.
Example: Diagramm for a cam timer
At the same time, a diagram plotted in this way also indicates the contour
of the equivalent program storage medium : working = peak (or material
present), rest = trough (or material cut away). A heavy line indicates that
the contact is closed.
For ease of cutting, the troughs should preferably be shorter than the peaks
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Basic concepts relating
to a timer
Introduction
Basic concept
Adjustable cam
a driving device: gearmotor
a program storage medium: adjustable, precut or striker cams
and output devices: microswitches, miniature valves
P2
P3
P1
of cycle
R
Start
T
0°
30°
30°
42°54°
Striker cam
Cycle duration = 1 min
170° 180°
180°
230°
240°250°270°280°
Precut cam
300°
End of cycle
360°
By convention, we have adopted these definitions:
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Basic definitions
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➜ In the same circuit
The minimum time is determined by the speed of cam movement and the
technology of each particular unit.
For cam timers : by providing a mechanical space sufficiently large to
enable the lever of the output device to drop.
In the individual specifications, the minimum time is given as a proportion
of a value which represents the duration of the program.
➜ Example :
or the type 88 645 cam timer, the minimum time is equal to 1/60th of the
total duration of a cycle.
The minimum interval is restricted solely by the mechanical strength of
the web of material between two successive spaces or by the thickness of
the strikers. It is given as a proportion of the same reference value as the
minimum time.
For the program storage medium, i.e. the cam, N repetitions of a pairing
of minimum time with minimum interval gives the maximum number of
switching operations by the output device which are possible. This
number is quoted in each specification.
Mechanical and electrical sizes
Accuracy and repeatability
Minimum time and interval
between 2 switching
Size of mechanical space : the actual dimension, measurable on the
program storage medium, of the feature which causes the contact to
change over
Size of electrical (or pneumatic) space : the electrical (or pneumatic)
result obtained.
Maximum repeatability error : (a)
Maximum possible difference between the theoretical size of a
Maximum repeatability error :
Maximum + or - error from the mean likely to be found for a number of
Switching interval :
Interval between any two points at which switching takes place (in the
switching interval and the value obtained.
measurements of an interval between two switching points.
same circuit or two different circuits) in a diagram.
Theoretical
switching
interval
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