26231941 Crouzet USA, 26231941 Datasheet - Page 142

• Manufacturer Part Number: 26231941
• Description: CAPACITOR, MOTOR MEDIUM TORQUE CAPACITOR, MOTOR MEDIUM TORQUE
• Manufacturer: Crouzet USA

Specifications of 26231941

• Capacitance: 0.1UF
• Voltage Rating, Dc: 700V
• Capacitor Dielectric Type: POLYPROPYLENE
• Tolerance,: 10%
• Tolerance, -: 10%
• Temp, Op. Max: 85(DEGREE C)
• Temp, Op. Min: 0(DEGREE

5
142
➜ Remarks on a given specification
For a given type of motor and number of phases several coil types are
available. They have been developed in order to adapt the motor to each
type of electronic control.
For example :
a low resistance is required for a DC supply and a higher resistance will
be appropriate for a constant voltage supply. However, all the coil types
are roughly equivalent from the point of view of power absorbed, ampere/
revolution and the (L/R) time constant (static).
These motors will have about the same performance for a given type of
electronic control.
Example motor 82 910 - 2 phases.
R
L
N
I e
NI
P
Z=L/R
➜ Step precision
Condition : (full stepping with 2 phases energised)
The external loads are nil, the current is at its nominal value.
Measurement is made on all the steps and for a complete rotation.
Definition:
Positioning precision
This is the variance with the theoretical equilibrium position.
Step precision
This is the variance of the movement angle (step)
➜ Influence of the inertia of the load
Fo - Maximum frequency of stopping-starting with no load inertia
JR - Inertia of the rotor
JL - Inertia of the load
Note :
The above formula is determined using the approximation JL ~ JR
➜ Notation
One phase of the motor has a resistance R and an inductance L
➜ Constant voltage supply
without a series resistor
The use of a series resistor necessitates the increase of the supply
voltage from :
U to R + Ro U
Power supplies
R
H
tr
A
A.tr
W
ms
in order to maintain the same
absorbed power to the motor.
82 910 001
9
12
320
0.52
166.4
4.9
1.3
with a series resistor
82 910 005
12.9
15
373
0.44
164
5
1.15
82 910 022
66
68
762
0.19
145
4.8
1
➜ Two-level voltrage supply
All the improvements are based on increasing the ramp at the source of
the current in the (R-L) circuit.
The first method consists of increasing the total resistance of the circuit.
The second method consists of increasing the supply voltage for a certain
time, with the average power dissipated within the motor not producing a
temperature rise above that permitted.
➜ Constant current supply
The supply voltage is considerably higher than the nominal RI. The
current is regulated by a transistor functioning in digital
mode following the given principle of chopper supplies
➜ Energisation «one phase at a time» «two phases at a
time»
Comparison at the same absorbed power
The holding torque is proportional to the current and is linear in the
magnetic region.
Beyond this, the phenomenon of saturation renders the holding torque
almost independent of the current.
Cm1 = Holding torque produced by phase 1 supplied by I
Cm2 = Holding torque produced by phase 2 supplied by I
I maximum
I average
I minimum
Comparisons
Power
Current per phase
Holding torque
1 phase at a time
P = R (rI)
r I
r
2
2 phases at a time
P = 2RI
I
r Cm
2