Unox MINDMaps BAKERTOP, Руководство по обслуживанию

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AIR.Maxi™ technology ensures perfect distribution of
the air and therefore of the heat within the cooking
chamber. Multiple auto-reversing fans and
high speed motors guarantee cookin g
uniformity in all pans: from those at the bottom of
the oven to those at the top. The possibility of
choosing from 4 air speeds and 4 semistatic modes
allows any type of product to be cooked perfectly,
from the most delicate items to products that
require high temperatures and a high rate of heat
transfer.
Motor
V
V
Marcia
Avviamento
M
I
M
I
A
I
A
I
V
V
Motor
Primary coil
I
I
A
I
P
I
P
I
A
I
π/ 4
π/ 4
figure 8
Asynchronous single phase motor scheme
Braking element
■ Braking element 1 (yellow wires) R = 75 Ω, 147 W,
105 V
■ Braking element 2 (red wires) R = 37,5 Ω, 100 W,
60 V
Speed
Braking
element 1
(yellow)
Braking
element 2
(red)
v 4 (max) R1 = 0 R2 = 0
v 3 R1 = 0 R2 = 1
v 2 R1 = 1 R2 = 0
v 1 (min) R1 = 1 R2 = 1
Air.Maxi
TM
The UNOX motor is equipped with two turns: one is
the primary and the other is the auxiliary and vice
versa on the basis of which the electrical current
passes through first.
The triac on the power board has the aim to switch
the current between the two turns ensuring the
inversion of the rotation.
In the electrical scheme of the MIND.Maps TM ovens,
the motors are connected in parallel. For each
motor, a capacitor has been installed and
connected in series with the motor itself and in
parallel with the other capacitors.
In the convection oven, the motors are used for
forcing the circulation of the air around food at
different speeds. The motor used is single phase
with asynchronous and it uses a system of capacitors
and a triac device integrated on the power board to
reverse the rotation. The stator winding is powered
by a sinusoidal voltage and it is crossed by a
sinusoidal current that generates an alternative
sinusoidal e.m.f (electromotive force). The sinusoidal
current produces an alternate magnetic field; that
field could be considered as the overlap of two
magnetic fields with the same value. This value
corresponds to the half of the maximum of each
alternate field. If the motor starts in a direction, it will
continue to run in that direction accelerating up to
the maximum speed. That phenomenon is due to
the fact that the torque of the field, spinning in the
same direction of the motor is greater than the
other one. To kick the motor UNOX AIR.Maxi
TM
technology uses a capacitor. The motor has a high
starting torque. The aim of the capacitor is to create
a difference of π/2 in the sinusoidal phase feeding
the turns inside the motor. In that way a double
phase rotating field is generated as shown in
The oven can manage 4 regular speeds in addition to
4 pulse speeds by alternatively activating the braking
elements. This is according to the scheme
summarized in
table 12
.
table 12
Braking element activation for speed adjustment
(0 stands for resistance not activated, 1 stands for
resistance activated)
Figure 8.
The asynchronous single phase motor runs at
maximum speed at standard voltage, normally 230
V AC 50 Hz for European markets, 208-240 V AC 60
Hz for the US. At this voltage, the motor runs at
around 2700-3000 RPM.
In order to slow down the motor, UNOX uses two
different braking elements: each of them is a
resistance connected in series with the motor and
able to drop the supply voltage to the motor itself.
The braking elements have the following technical
specifications:
71