Carrier NDK33BN0KB, Руководство по эксплуатации и обслуживанию

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62-61753-21 4-9
The primary time that it is important to determine
which range is to be Range 1 and which is to be
Range 2 is when the ranges overlap each other.
In example 2 (see Figure 4-3), the ranges have been
set to lock all setpoints into Start-Stop, except for a
small range between 0° and 5.6°C (+32° and +42°F)
where the unit will always operate in Continuous Op-
eration. Range 1 Minimum Temperature has been set
for 0°C (+32°F), and Maximum Temperature of 5.6°C
(+42°F). Range 2 has been set for a Minimum Tem-
perature of -30°C (-22°F) and a Maximum Tempera-
ture of 32°C (+89.6°F).
4.6.3 ProductShield
ProductShield is a group of Configurations which may
be set to provide enhanced product or unit protection
under extreme ambient conditions. There are four
ProductShields: Econo - Go to Start/Stop, Econo - Go
to Continuous, High Air and Winter.
a. ProductShield: Econo: Go To Start/Stop
When the unit is in Continuous Operation, Prod-
uctShield - Go to Start/Stop allows the operator to
select ambient temperature conditions under which the
unit may operate in Start/Stop.
In addition, the operator may also set a Delta T value,
that is the difference between the return air and supply
air sensors.
When the unit is set for Continuous Operation, Prod-
uctShield Econo: Go To Start/Stop allows the unit to
change to Start/Stop when the unit has run in Continu-
ous Operation for a minimum of 15 minutes and the
ambient temperature falls
within a pre-programmed
temperature range. (Refer to Section 4.6.4). The oper-
ator can also pre-program a maximum temperature
differential (delta-t) between the return air and supply
air sensors as an additional criteria for switching to
Start/Stop if the Econo Delta-T Configuration is not
OFF. The unit must bring the delta-t below this setting
before going to Start/Stop if this option is chosen. If
unit is set for Continuous Operation and ProductShield
Econo is configured for GO TO CONTINUOUS, the
unit will remain in Continuous Operation.
Once the micro detects that the above criteria have
been met, the unit will switch from Continuous Opera-
tion to auto Start/Stop for a minimum of 30 minutes or
until the unit cycles off. After 30 minutes the unit will
return to Continuous Operation once the ambient tem-
perature falls
outside the pre-programmed tempera-
ture range by ±2°C (±3.6°F).
If the unit shuts down in Auto Start/Stop, it will remain
shut down according to the pre-programmed start/stop
parameters. When the unit restarts it will return to Con-
tinuous Operation for a minimum of 15 minutes. The
original activation conditions must again be met in
order for the unit to return to auto Start/Stop.
b. ProductShield: Econo: Go To Continuous Op-
eration
When the unit is set for Start/Stop, ProductShield
Econo: Go To Continuous Operation allows the unit to
run in Continuous Run for periods providing Prod-
uctShield Econo Configuration is set to GO TO CON-
TINUOUS (Refer to Section 5.1.1), the unit has run in
Start/Stop for a minimum of 15 minutes or the Mini-
mum Run Time minus 60 seconds (Refer to Table 3-2)
and the ambient temperature falls
outside a pre-
programmed temperature range. If unit is set for
Start/Stop and ProductShield Econo is configured for
GO TO START/STOP, the unit will remain in
Start/Stop.
Once the micro detects that the above criteria have
been met, the unit will switch from Start/Stop to Con-
tinuous Operation for a minimum of 30 minutes. After
30 minutes the unit will return to Continuous Operation
once the ambient temperature falls
within the pre-
programmed temperature range by ±3.6°F (±2°C).
Delta-t logic is not used when unit is configured for GO
TO CONTINUOUS.
c. ProductShield: High Air
High air mode allows the unit to provide increased
airflow with a reduced delta-T under the pre-
programmed criteria. This can maximize product pro-
tection under difficult conditions while allowing the unit
to operate more efficiently during less demanding con-
ditions.
When the refrigeration unit is set for normal airflow,
ProductShield High Air allows the unit to run at high air
operation for periods providing the ambient tempera-
ture falls within a pre-programmed temperature range.
The operator can also pre-program a maximum tem-
perature differential (delta-t) between the return air and
supply air sensors as an additional criteria for switch-
ing to high air if the Econo Delta-T Configuration is not
OFF. The unit must bring the delta-t above this setting
before going to high air if this option is chosen.
Once the micro detects that the pre-programmed crite-
ria have been met, the unit will switch from normal
operation to High Air. The unit will continue to operate
in High Air for a minimum of 30 minutes. After
30 minutes the unit will return to normal operation
once the ambient temperature falls outside the pre-
programmed temperature range by ±3.6°F (±2°C).
If the unit shuts down in Auto Start/Stop during high
speed, it will not be in ProductShield High Air when it
restarts and will return to normal operation for a mini-
mum of 15 minutes. The original activation conditions
must then be met in order for the unit to return to high
air.
d. ProductShield: Winter
When the unit is set for Start/Stop operation, Prod-
uctShield Winter allows it to switch to Continuous Op-
eration when the ambient temperature falls below a
pre-programmed temperature. This will protect the unit
from the complication of fuel gelling.
Once the micro detects that the ambient temperature
has dropped below the pre-programmed temperature,
the unit will switch from auto Start/Stop to Continuous
Operation. The unit will continue to operate in Contin-
uous Operation for a minimum of 30 minutes. After 30
minutes, the unit will return to auto Start/Stop once the
ambient temperature has risen more than 3.6°F (2°C)