Turboair SMART 7 STI030MR404A1 User manual

Turbo air Speeds Up the Pace of Innovation
Part No. KUCST1307
CAREL CONTROLLER
Refrigeration System
Installation & Operation Manual
Please read this manual completely before attempting to install or operate this equipment !
Package Unit ( TOP MOUNT )

2

3
CONTENTS
Safety Information …………………………………… 4
Inspection ……………………………………………… 4
Locating SMART 7 Package Unit…………………… 7
Installation Procedure ………………………………… 9
Sequence of Operation ……………………………… 11
Controller Setting …………………………………… 12
System Troubleshooting …………………………… 25
Electrical Wiring Diagram…………………………… 26

4
Safety Information
Be sure all power sources are turned off before checking the electric wiring or appliances to
avoid electric shock.
Do not run fan if cover or case is removed. This is to avoid electric shock.
Keep finger away from moving parts.
Avoid touching refrigerant lines. Some parts are very hot and can cause burns.
Avoid contacting sharp edges or coil surface that are a potential injury hazard.
Avoid touching the units or electric box in wet hands to prevent electric shock.
Please call the specialized installation company or trained personnel when you installing,
moving, operating of the unit.
Field wiring must confirm to the requirements of units’ electric specification.
Inspection
A person at the job site to receive material holds responsibility. Each shipment should be
carefully inspected against the bill of lading. The shipping receipt should not be signed before
careful inspection. Check carefully for concealed damage. Any shortage or damages should be
reported to the delivering carrier. If damaged material becomes the delivering carrier’s
responsibility and it should not be returned to Turbo air unless prior approval is given to do so.
Check the serial tag information with invoice. Report any discrepancies to Turbo air sales
representatives.

5
Table 1. INDOOR UNIT - Medium Temperature (Air Defrost System)
Model
Ambient 95
℉
Voltage MCA MOPD
Refrigerant.
Plug
Supplied
Matching
NEMA
Receptacle
NET
Weight
(Lbs)
Fig.
Capacity BTUH Ref. Wt
oz
35
℉
38
℉
STI030MR404A1 3183 3380 115/1/60 7.1 15 R404A 18 YES 5-20R 130 A
STI050MR404A1 5026 5356 115/1/60 11.3 20 R404A 28 YES 5-20R 195 B
STI050MR404A2 5026 5356 208~230/1/60 4.7 15 R404A 28 YES 6-15R 195 B
STI068MR404A2 7743 8213 208~230/1/60 8.9 15 R404A 42 YES 6-15R 216 B
STI075MR404A2 8059 8675 208~230/1/60 9.2 15 R404A 42 YES 6-15R 226 B
STI100MR404A2 11652 12556 208~230/1/60 14.0 20 R404A 53 YES 6-20R 311 C
STI100MR404A3 11652 12556 208~230/3/60 10.1 15 R404A 53 NO - 318 C
STI130MR404A2 15092 16376 208~230/1/60 14 20 R404A 60 NO - 320 C
STI130MR404A3 15092 16376 208~230/3/60 9.9 15 R404A 60 NO - 317 C
Table 2. INDOOR UNIT – Low Temperature (Electric Defrost System)
Model
Ambient 95
℉
Voltage MCA MOPD
Refrigerant.
Plug
Supplied
Matching
NEMA
Receptacle
NET
Weight
(Lbs) Fig.
Capacity BTUH
Ref. Wt
oz
0℉−10℉−20℉
STI022LR404A2
2849
2423
1643
208~230/1/60
8.0
15
R404A
24
YES
6-15R
195
B
STI045LR404A2
5957
4603
3514
208~230/1/60
16.4
25
R404A
28
YES
6-15R
226
D
STI055LR404A2
7395
5406
4002
208~230/1/60
19.5
30
R404A
46
YES
6-20R
311
C
STI055LR404A3
7395
5406
4002
208~230/3/60
13.3
20
R404A
46
NO
-
318
C
STI070LR404A2
9139
7520
5439
208~230/1/60
19.8
30
R404A
46
NO
-
320
C
STI070LR404A3
9139
7520
5439
208~230/3/60
13.9
20
R404A
46
NO
-
317
C
Table 3. OUTDOOR UNIT - Medium Temperature (Air Defrost System)
Model
Ambient 95
℉
Voltage MCA MOPD
Refrigerant.
Plug
Supplied
Matching
NEMA
Receptacle
NET
Weight
(Lbs)
Fig.
Capacity BTUH
Ref. Wt
oz
35
℉
38
℉
STI050MR404A2 5026 5356 208~230/1/60 4.7 15 R404A 28 NO - 205 D
STI068MR404A2
7743
8213
208~230/1/60
8.9
15
R404A
42
NO
-
225
D
STI075MR404A2 8059 8675 208~230/1/60 9.2 15 R404A 42 NO - 236 D
STI100MR404A2
11652
12556
208~230/1/60
14.0
20
R404A
53
NO
-
319
E
STI100MR404A3 11652 12556 208~230/3/60 10.1 15 R404A 53 NO - 327 E
STI130MR404A2 15092 16376 208~230/1/60 14 20 R404A 60 NO - 329 E
STI130MR404A3 15092 16376 208~230/3/60 9.9 15 R404A 60 NO - 325 E
Table 4. OUTDOOR UNIT – Low Temperature (Electric Defrost System)
Model
Ambient 95
℉
Voltage MCA MOPD
Refrigerant.
Plug
Supplied
Matching
NEMA
Receptacle
NET
Weight
(Lbs)
Fig.
Capacity BTUH
Ref. Wt
oz
0
℉
−10
℉
−20
℉
STX022LR404A2
2849
2423
1643
208~230/1/60
8.0
15
R404A
28
NO
-
213
D
STX045LR404A2
5957
4603
3514
208~230/1/60
16.4
25
R404A
42
NO
-
248
D
STX055LR404A2
7395
5406
4002
208~230/1/60
19.5
30
R404A
53
NO
-
320
E
STX055LR404A3
7395
5406
4002
208~230/3/60
13.3
20
R404A
53
NO
-
317
E
STX070LR404A2
9139
7520
5439
208~230/1/60
19.8
30
R404A
60
NO
-
328
E
STX070LR404A3
9139
7520
5439
208~230/3/60
13.9
20
R404A
60
NO
-
324
E

6
Figure A. INDOOR UNIT – Small Cabinet (Opening Size : 14.5 inch x 20.8 inch)
Figure B. INDOOR UNIT – Medium Cabinet (Opening Size : 25 inch x 25 inch)
Figure C. INDOOR UNIT – Large Cabinet (Opening Size : 25 inch x 38.5 inch)
Figure D. OUTDOOR UNIT – Medium Cabinet (Opening Size : 25 inch x 25 inch)
Figure E. OUTDOOR UNIT – Large Cabinet (Opening Size : 25 inch x 38.5 inch)

7
Locating SMART 7 Package Unit
Unit Installation Requirements
1. You must ensure before unit placement on the roof of box that the structural strength of the
box can withstand the weight of SMART7 equipment
2. The unit should be installed away from noise sensitive site and must have proper support for
noise and vibration not to be transmitted into the building.
3. Unit must be located away from steam, hot air or heat generator and placement should be
selected in consideration of ventilation.
4. Indoor units are designed for indoor use only with ambient between 50℉~100℉and have no
system control following ambient variation.
5. Evaporator section must not be located over doors.
6. Air circulation must cover completely inner space.
7. Installation, service and maintenance must be carried out by licensed contractor in conformity
with the local standard construction code.
Ignoring above requirement will result in system fault, shorten life span and void the warranty,
Unit Transport Requirements.
1. Do not remove shipping skid until ready to move it upon box rooftop.
2. Always watch out not to contact sharp edges and coil surfaces to avoid potential injury. Wear
safety gears always during installation.
3. Use spreader bar to lift the unit upon roof of box not to damage on the cabinet.
4. Do not remove compartment cover of the compressor section, hood for outdoor unit.
Unit Installation location.
1. Space between wall and air in/outlet must be secured at least 2inch.(refer to Fig. 1)
2. There must be 2 feet space secured at least above unit for service and removal of top
case.(Refer to Fig. 1)
3. Single unit installation must be carried out following Fig. 2.
4. More than dual units installation must be carried out following Fig. 3.

8
Figure 1. Minimum Clearance at Installation of Unit.
W = UNIT WIDTH
Figure 2. One Unit
W = UNIT WIDTH
Figure 3. Two or more Unit

9
Installation procedure
Indoor use only ( STI Model )
1. Carefully check package for damages during transportation and unit after opening the
package.
2. Requirements must be followed for installing location on the page of 6~7.
3. Ensure weights of units on the page of 4~5 and that structural strength of the box can
withstand of the weight of the unit.
4. Clean the roof surface of box for close adhesion of unit gasket to the surface.
5. Consult to box manufacturer for any processes necessary to ensure the integrity of the
exposed form in the panels is not compromised.
6. Check mounting surface as level of surface should be within 1/8inch per a feet.
7. Place carefully unit into the provided opening with the evaporator air flow directly forward the
door and ensure the grill not to damage during installation.
8. Secure that the condenser airflow is not obstructed.
9. Drain is not needed as condensate is vaporized by hot gas lines in the drain panel from the
compressor discharge.
10. Install trim pieces around the open on the ceiling of box.
Outdoor use only ( STX Model )
Installation is the same as indoor models except as follows :
1. Units must be curb mounted ( Figure 4 ~ 5 ). Cabinet size refer to dimension size on page 5.
2. The condensate drain outlet pipe is located on the side of the unit. Field piping may be
connected to the outlet provided it is adequately sloped and heated for freezing weather
conditions.
3. After connecting electrical power, reinstall compressor compartment cover and weather hood.
Figure 4. Curb placed on roof of box. Figure 5. Roof membrane placed over curb.

10
Check before Unit Start-up.
1. Check all electrical and refrigerant connections.
2. Observe all applicable building and electrical codes when wiring.
3. Make sure power supply has correct voltage and phase for unit and is fused properly.
4. If unit is connected with a power cord, use the cord with plug to connect to power supply.
If unit is not connected with a power cord, use hard wire to connect to power supply.
IMPORTANT
Do not use extension cords to connect unit to power.
Plug-in to grounded three prong outlet.
Do not remove grounding prong.
Do not use a power adapter.
5. All medium and low Temperature Models are preset to factory default settings at table 5.
Standard Maintenance Guideline.
After first year of operation and under normal usage, maintenance should cover the following
items at least once every six months.
1. Check all electrical and refrigerant connections.
2. Check all wiring and insulators.
3. Check contactors for proper operation and for state of contact points.
4. Check all fan motor. Tighten motor mount bolts, nuts and fan set screws.
5. Clean the heatexchanger (evaporator and condenser) coil surface.
6. Check the operation of the control system. Make sure all safety controls are operating
properly.
7. Check the defrost control system. Make sure all defrost controls are operating properly.
8. Check the drain pan and drain line. If necessary, clean the drain pan and drain line.
9. Check the all heaters. Make sure the crankcase and drain line heaters are operating properly.
After installation of unit, it must be checked at least once for proper defrosting. The amount and
pattern of frosting can vary considerably. It is dependent on the temperature of the room, the
type of product being stored, how often new product is brought into the room and how often
door is opened. Therefore, it may be necessary to periodically change the number of defrost
cycles or adjust the duration of defrost.

11
Sequence of Operation.
Operation of Refrigeration.
1. When switch is turned on, power is provided to the temperature control, compressor,
condenser and evaporator fan motor. And they will run until the box temperature setting is
reached.
2. When the box temperature reaches a setting, the compressor and condenser fan motors shut
off while evaporator fan motor is working.
3. When the box temperature rises above the set point and minimum off-time has elapsed, the
compressor contactor will be re-energized and re-operated.
Operation of Defrost.
1. Under normal electric defrost operation, the temperature/defrost control will de-energize the
compressor contactor, evaporator fans and energize the defrost heaters. But under normal air
defrost operation, the control will de-energize the compressor contactor and keep an
evaporator fan motor working.
2. When the coil has defrosted completely and reached the preset coil sensor temperature,
defrost heater cuts off and fan delay / drip sequences begin.
3. The control energizes the compressor and condenser fan motor and they restart.
4. When the coil temperature reaches 65℉or fan delay time has elapsed, the evaporator fans
will be energized and started.

12
Controller Setting.
Carel PJEZC Electronic Controller.
The most complete solution for low temperature ventilated units, with three relays for complete
control of the compressor, fan and defrost functions. The three relays are included in the very
compact case in the versions with 230 V or 115 V power transformer, without compromising
the performance or reliability of the product.
Panel installation using 2 rear brackets
• insert the instrument in the opening (phase 1);
• secure the instrument by sliding the brackets in the guides on the instrument until compressing
them against the panel (phase 2);
Figure 6. Controller installed method
Electrical Connections
WARNINGS:
• the electrical connections must only be completed by a qualified electrician;
• a power supply other than the type specified may seriously damage the system;
• separate as much as possible the probes and digital input signal cables from the cables
carrying inductive loads and power cables to avoid possible electromagnetic
disturbance. Never lay power cables(including the electrical cables) and probe signal
cables in the same conduits. Do not install the probe cables in the immediate vicinity of
power devices (contactors, circuit breakers or similar);
• reduce the path of the probe and sensor cables as much as possible, and avoid spiral
paths that enclose power devices. The probes must be connected using shielded cables
(minimum cross-section of each wire: 0.5 mm2);
• avoid direct contact with internal electronic components;
• connection errors (and connections other than those indicated in this manual) may
involve danger to the safety of the users and cause faults on the instruments and the
components connected;
• fit the unit with all the electromechanical safety devices required to guarantee correct
operation and the complete safety of the user.

13
The buttons;
Figure 7. Display Figure 6. Keypads
Display
BUT.
NO FUNCTION
NORMAL OPERATION
START UP
ON
OFF
FLASH
1
COMPRESSOR
ON
OFF
CALL
ON
2
FAN
ON
OFF
CALL
ON
3
DEFROST
ON
OFF
CALL
ON
4
Auxiliary output (AUX)
Output active
Output not active
-
ON
5Clock (RTC) RTC available, enabled (tEN=1) and
at least one time band has been set
RTC not available or not enabled
(tEN=0) or no time band set
ON (if the clock
is fitted)
6
alarm
alarm in progress
no alarm in progress
on
7digits three digits with decimal point and range -199 to 999. See parameters /4, /5, /6 for the type of probe displayed, values
in °C/°F and decimal point
Keypads
BUT
NO.
NORMAL OPERATION
START UP
pressing the button alone pressing with other buttons
1 more than 3 s: switch ON/OFF pressed together with 3 activates / deactivates
the continuous cycle
2
- 1 s: displays/sets the set point
- more than 3 s: accesses the parameter
setting menu (enter password 22)
- mutes the audible alarm (buzzer)
for 1 s RESET
current EZY set
Pressed
together (2 and
3) activate
parameter
reset procedure
3 more than 3 s: activates / deactivates the
defrost
pressed together with 1 activates / deactivates
the continuous cycle
for 1 s displays
firmware version
Preliminary configurations
Once the electrical connections have been completed, simply power-up the controller to make it
operative.
Turbo air recommends to check that the display does not show any alarm signals (see par.
Table 7), and finally set the parameters as desired (see par. Table 5,6).
The main parameters are as follows:
Control parameters Defrost parameters Alarm parameters
st set point d0 type of defrost Ad temperature alarm delay
rd set point differential dI interval between two defrosts AL low temperature alarm threshold/deviation
dt end defrost temperature AH high temperature alarm threshold/deviation
dP maximum defrost duration

14
Functions available from the keypad.
On and off
Switching the instrument ON : press UP for more than 3 s (when pressing the button, the
display shows ON).
Switching the instrument OFF : press UP for more than 3 s. The display shows the message
“OFF”, alternating with the temperature measured by the set probe.
In OFF status, the following functions are disabled (if featured by the model):
• compressor control / duty setting / continuous cycle;
• defrost;
• fan control;
• alarms : ‘LO’, ‘HI’, ‘IA’, ‘cht’, ‘CHT’;
• door switch: A4=7/8
• buzzer (when available).
While the following are enabled:
• temperature display, alternating with the message “OFF”;
• parameter display and setting;
• alarms: “E0”, “E1”, “E2”;
• the internal timer relating to parameter ‘dI’ is updated. If ‘dI’ expires in OFF status, a defrost is
performed when restarting;
• auxiliary relay management, only in the following configurations:
– H1= = 1/2 (“E0” alarm only);
– H1= 3, A4= 6;
WARNINGS:
• when first connected, easy is already on and ready to be used;
• the instrument can be switched on from a supervisor PC and via an external contact
(setting A4= 5). The latter has priority over the other modes.
Set point setting (desired temperature value)
The easy, easy compact devices control the desired temperature (set point) inside the cabinet
or cold room directly and dynamically.
To view and modify the set point:
• press SET for 1 s, the set value will start fl ashing;
• increase or decrease the value using UP or DOWN;
• press SET to confirm the new value.

15
Manual defrost
Press DOWN for more than 3 s (activated only if the temperature conditions are right).
Continuous cycle
Press UP+DOWN for more than 3 s (activated only if the temperature conditions are right and
for easy split only when H6=0).
The continuous cycle is used to maintain refrigeration active in the cabinet or cold room,
regardless of the temperature inside the unit. This may be useful for rapidly bringing the
temperature below the set point value.
Rapid display of the temperature read by the other probes
Press the DOWN button to scroll the temperatures read by the probes. Each time the DOWN
button is pressed, the display will show the name of the probe Pr1, Pr2 or Pr3 (only on the
models with 3 inputs and with multifunction input configured as a probe) and after 1 s the
temperature measured by the selected probe will be displayed.
To display the other probes, press DOWN again.
To return to the normal display, wait 3 s without pressing any buttons (exit by timeout).

16
Device setup.
Rapid parameter set selection (EZY)
The easy controllers feature the EZY parameter which is used to quickly choose a list of
parameters, with corresponding values, for the control of the refrigeration system.
Table 5. SET 1 (EZY=1) – Low temperature (SET POINT : -10
℉
) Electric defrost
Parameter
Description
Min
Max
Default
St Set point -30 30 -10
r1 Minimum set point value -50 30 -30
r2 Maximum set point value -30 150 30
c2 Minimum compressor off time 0 100 4
do Type of defrost 0 4 0
dl
Interval between defrost
0
199
6
dt
End defrost temperature set point
-50
127
65
dP
Maximum defrost duration
1
199
60
d4
Defrost on power-up
0
1
1
dd
Dripping time
0
15
2
F0
Enable evaporator fan control
0
1
0
F2
Stop evaporator fan if compressor stop
0
1
0
F3
Evaporator fan status during defrost
0
1
1
Fd
Post-dripping time
0
15
2
Table 6. SET 2 (EZY=3) – Medium temperature (SET POINT : 38
℉
) Air defrost
Parameter
Description
Min
Max
Default
St Set point 0 50 38
r1 Minimum set point value -50 50 0
r2 Maximum set point value 0 150 50
c2 Minimum compressor off time 0 100 4
do
Type of defrost
0
4
2
dl
Interval between defrost
0
199
6
dt
End defrost temperature set point
-50
127
40
dP
Maximum defrost duration
1
199
40
d4
Defrost on power-up
0
1
0
dd
Dripping time
0
15
0
F0
Enable evaporator fan control
0
1
0
F2
Stop evaporator fan if compressor stop
0
1
0
F3
Evaporator fan status during defrost
0
1
0
Fd
Post-dripping time
0
15
0

17
Table of alarms and signals.
When an alarm is activated, the display shows the corresponding message that flashes
alternating with the temperature; if fi tted and enabled, the buzzer and the alarm relay are also
activated.
All the alarms have automatic reset (that is, they stop when the causes are no longer present),
except for alarm ‘CHt’ which has manual reset (instrument on/off using the UP button or by
disconnecting the power supply).
Pressing the SET button mutes the buzzer, while the code displayed and the alarm relay only
go off when the causes of the alarm have been resolved.
The alarm codes are shown in the table below:
Table 7. Alarm codes table.
alarm
code
buzzer and
alarm relay LED alarm description reset enable alarm parameters involved
E0 active on probe 1 error = control automatic
E1 not active on probe 1 error = defrost automatic d0=0/1/4, F0=1
E2 not active on probe 1 error =
condenser/product automatic A4=10
IA active on external alarm automatic A4=1, +A7
dOr active on open door alarm automatic A4=7/8, +A7
LO active on low temperature alarm automatic AL, Ad
HI active on high temperature alarm automatic AH, Ad
EE not active on unit parameter error not possible
EF not active on operating parameter error manual
Ed not active on defrost running on first defrost
ended correctly dP, dt, d4, A8
dF not active off defrost running automatic d6=0
cht not active on dirty condenser pre-alarm automatic A4=10
CHT active on dirty condenser alarm manual A4=10
EtC not active on clock alarm by setting the
time if bands active

18
Description of the main signals and alarms.
LED flashing
The activation of the corresponding function is delayed by a timer, awaiting an external signal or disabled
by another procedure that is already in progress. e.g. if is a continuous cycle in progress and a defrost is
called, the latter will remain pending until the end of the continuous
cycle, and the corresponding LED (defrost) will flash.
E0 steady or flashing
control probe error:
• probe not working : the probe signal is interrupted or short-circuited;
• probe not compatible with the instrument;
The alarm signal E0 is steady if it is the only active alarm (the temperature value is not displayed), while it
flashes if other alarms are active or the second probe is displayed.
E1 flashing
evaporator probe or food conservation probe error:
• probe not working, the probe signal is interrupted or short-circuited;
• probe not compatible with the instrument;
E2 flashing
condenser probe or food conservation probe error:
• probe not working, the probe signal is interrupted or short-circuited;
• probe not compatible with the instrument;
IA flashing
immediate or delayed alarm from multifunction digital input:
• check the multifunction input and parameters A4 and A7.
dOr flashing
open door alarm:
• check the multifunction input and parameters A4 and A7.
LO flashing
low temperature alarm. The probe has measured a temperature lower than the set point by a value that
exceeds parameter AL:
• check parameters AL, Ad and A0.
The alarm is automatically reset when the temperature returns within the set limits (see parameter AL).

19
HI flashing
high temperature alarm. The probe has measured a temperature higher than the set point by a value that
exceeds parameter AH.
• check parameters AH, Ad and A0.
The alarm is automatically reset when the temperature returns within the set limits (see parameter AH).
EE displayed during operation or on power-up
unit parameter reading error. See Data errors.
EF displayed during operation or on power-up
operating parameter reading error. See Data errors.
Ed flashing
The last defrost ended after exceeding the maximum duration rather than when reaching the end defrost
set point.
• check parameters dt, dP and d4;
• check the effi ciency of the defrost.
The message disappears when the next defrost ends correctly.
dF flashing
defrost running:
• this is not an alarm signal, but rather a message that the instrument is running a defrost. Only shown if
d6= 0.
cht flashing
dirty condenser pre-alarm:
• check parameters A4, Ac, AE and Acd.
CHt flashing
dirty condenser alarm:
• check parameters A4, Ac, AE and Acd.
EtC flashing
internal clock error.
Data error
In certain operating conditions, the instrument may detect errors in the data saved. These errors
may compromise the correct operation of the instrument. If the microprocessor detects a data
saving error, the display shows the message “EE”.
If the fault persists, the controller needs to be replaced. If, on the other hand, the message
disappears, it can continue to be used. When “EE” error occurs frequently and/or remains for
some time, the controller should be checked, as the original precision may not be guaranteed.

20
Modifying the parameters.
Parameter navigation
The operating parameters, modifiable using the keypad, are divided into two types: frequent
(type F) and confi guration (type C). Access to the latter is protected by password (default= 22)
to prevent accidental or unauthorised modifications.
Accessing the type F parameters:
• press the SET button for more than 3 s (if there are active alarms, mute the buzzer). The
display shows the parameter code ‘PS’ (password);
• use the UP and DOWN buttons to scroll the parameters. The LED corresponding to the
category of parameters will be on (see Table 8);
• press SET to display the value associated with the parameter
• increase or decrease the value using the UP or DOWN button respectively;
• press SET to temporarily save the new value and display the parameter again;
• repeat the procedure for any other parameters that need to be modified;
• press the SET button for more than 3 s to permanently save the parameters and exit the
parameter setting procedure.
Accessing the type C parameters:
• press the SET button for more than 3 s (if there are active alarms, mute the buzzer), the
display shows the parameter code “PS” (password);
• press the SET button to access the password setting;
• use the UP and DOWN buttons to scroll the numbers until displaying “22” (password to access
the parameters);
• press the SET button to confi rm the password;
• use the UP and DOWN buttons to scroll the parameters. The LED corresponding to the
category of parameters will be on (see Table 8);
• press SET to display the value associated with the parameter;
• increase or decrease the value using the UP or DOWN button respectively;
• press SET to temporarily save the new value and display the parameter again;
• repeat the procedure for any other parameters that need to be modified;
• press the SET button for more than 3 s to permanently save the parameters and exit the
parameter setting procedure.