TK 56433-5-MM-EN
21
OptiSet Plus™
OptiSet Plus is a group of programmable functions that
control how the unit will operate with specific setpoints
or named products. This assures that when a particular
setpoint or named product is selected, the unit will
always operate the same way. This allows an entire
fleet to be configured to match customers’ needs. Refer
to the SR-3 Trailer Single Temperature SL-400e, SLX/
SLXe/SLXi Series Diagnostic Manual TK 56487 and
OptiSet Plus Help for configuration instructions..
FreshSet™
FreshSet is included in OptiSet Plus. FreshSet is a
demand base temperature control for fresh products.
FreshSet modifies and adjusts unit airflow operation to
control temperature and to maximize protection of
cargo, while keeping operating costs to a minimum.
Refer to the SR-3 Trailer Single Temperature SL-400e,
SLX/SLXe/SLXi Series Diagnostic Manual TK 56487 for
configuration instructions.
Sequence of Operation
When the Microprocessor On/Off switch is turned on
and Controller ON key is pressed, the LCD display is
illuminated and shows the setpoint and the return air
temperature. If the CYCLE-SENTRY mode has been
selected, the unit will start and stop automatically. If
the Continuous mode has been selected, the unit will
start and run automatically.
Operating Modes
The microprocessor uses a complex program to
determine which operating mode the unit should be in.
Therefore, it is difficult to predict which operating
mode the unit should be in by comparing the setpoint
to the box temperature.
The diesel engine operates at either low speed or high
speed as determined by the microprocessor. The unit
will Cool or Heat in either high or low speed. The unit
will Defrost in low speed only. Heat and Defrost
consists of hot gas delivered to the evaporator coil
distributor.
The microprocessor will select the operating mode
from the following:
•
High Speed Cool
•
Low Speed Cool
•
Low Speed Modulated Cool
•
Null (CYCLE-SENTRY operation only)
•
Low Speed Modulated Heat
•
Low Speed Heat
•
High Speed Heat
•
Defrost
Defrost
Frost gradually builds-up on evaporator coils as a
result of normal operation. The unit uses hot
refrigerant to defrost the evaporator coils. Hot
refrigerant gas passes through the evaporator coil and
melts the frost. The water flows through collection
drain tubes onto the ground. The methods of Defrost
initiation are Automatic and Manual.
A
Au
utto
om
ma
attiicc D
De
effrro
osstt:: The controller is programmed to
automatically initiate timed or demand defrost cycles.
The controller can be programmed to initiate timed
defrost cycles at intervals of 2, 4, 6, 8, or 12 hours.
Demand defrost cycles occur if the differences between
the return air temperature, discharge air temperature,
and coil temperature exceed certain limits. The unit can
enter defrost cycles as often as every 30 minutes if
required.
M
Ma
an
nu
ua
all D
De
effrro
osstt:: In Manual Defrost Mode, the operator
initiates a defrost cycle. See the appropriate Diagnostic
or Operator’s Manual.
N
No
otte
e:: The unit will not perform a Manual Defrost cycle
unless the unit has been turned on with the ON
key, the unit is running in Continuous or CYCLE-
SENTRY mode (or shut down in CYCLE-SENTRY
Null mode), and the coil temperature is below 45
F (7 C).
The evaporator coil temperature must be below 45 F (7
C) to allow defrost.
The following four defrost timers are used. These
timers can be set for intervals of 2, 4, 6, 8 or 12 hours.
•
Defrost Interval In Range with Fresh Setpoint
(standard setting 6 hours)
•
Defrost Interval Not In Range with Fresh Setpoint
(standard setting 4 hours)
•
Defrost Interval In Range with Frozen Setpoint
(standard setting 6 hours)
•
Defrost Interval Not In Range with Frozen Setpoint
(standard setting is 4 hours)
This feature allows a shorter Defrost interval to be used
when the unit is out of range during a pull-down and
more frequent Defrost cycles may be beneficial.
Normally, longer defrost timer intervals are used for
colder loads. The defrost interval may need to be
changed if the unit will not hold the compartment
temperature at setpoint.
Use a longer defrost interval if defrost is not being
initiated on demand.
Use a shorter defrost interval if defrost is frequently
being initiated on demand.
If the unit is in CYCLE-SENTRY Null mode, the engine
will start when defrost is initiated. The unit will stay in
defrost until the evaporator coil temperature rises to 58
F (14 C).
