Huazheng DHG Series User manual

DHG Series
Electrothermal Blast Drying Oven
（with Intelligent Timing）
Huazheng Electric Manufacturing (Baoding) Co., Ltd

Dear use r:
Thank you for choosing DHG Ser ies Electrotherma l Blast Drying Ove n
（with Intel ligent Timing）.
We hope that this instrum ent can mak e your wo rk easier an d mo re
en jo ya bl e, so tha t you can ge t th e feeling of office aut om at ion in the test
an d analysis work.
Before using the instrument, please read this man ua l, an d op er ate and
maintain the inst rume nt according to the manual to pro lo ng its se rvice li fe.
"Just a lig ht pr ess, th e test wi ll be completed automatically " is the
op er atin g charact eristics of this inst rument.
If you ar e sat isfied wi th th is instrument, please tell yo ur colleagues;
if yo u are no t sat isfied wi th this inst rume nt, ple ase call [phone] to
tell you to serve you at all tim es -Baoding Huazheng Ele ct ric Manufac tu ring
Co. , Ltd., our compa ny will definitely mak e yo u satisfied !

Contents
I.Scope of application ：............................................................................................................... 1
II.Technical indicators：................................................................................................................. 1
III.Summary of structure................................................................................................................. 2
IV.Method of use..............................................................................................................................2
V.1.Panel Instructions..................................................................................................................... 3
VI.Matters needing attention ：................................................................................................... 9
VII.Fault handling：........................................................................................................................ 9
VIII.Packing list：.......................................................................................................................... 10

1
I.Scope of application ：
For industrial enterprises, universities and colleges, scientific research and related
laboratory for items, drying, baking, wax melting and sterilization.
II.Technical indicators：
Model
9030A
9070A
9140A
9240A
9420A
9620A
The power supply
voltage
AC220V 50Hz
AC380V 50Hz
Range of temperature
RT+10℃～200℃
Temperature resolution
0.1℃
Temperature uniformity
±2.5℃%
Temperature fluctuation
degree
±1.0℃
Rated power
700W
1000W
1600W
2000W
2600W
3600W
The tank size (cm)
30×30×35
40×40×4
5
45×55×
55
50×60×7
5
60×55×13
0
80×60×13
0
Overall dimensions(cm)
45×47×70
55×60×8
0
64×73×
90
88×72×9
3
78×71×17
8
98×80×17
8
Shelf
2pcs
2pcs
2pcs
2pcs
3pcs
3pcs
Model
9036A
9076A
9146A
9246A
9426A
9626A
The power supply
voltage
AC220V 50Hz
AC380V 50Hz
Range of temperature
RT+10℃～300℃
Temperature resolution
0.1℃
Temperature uniformity
±2.5℃%
Temperature fluctuation
degree
±1.0℃
Rated power
950W
1400W
2000W
2600W
3500W
3700W

2
The tank size(cm)
30×30×35
40×40×4
5
45×55×
55
50×60×7
5
60×55×13
0
80×60×130
Overall dimensions(cm)
45×47×70
55×60×8
0
64×73×
90
88×72×9
3
78×71×17
8
98×80×178
Shelf
2pcs
2pcs
2pcs
2pcs
3pcs
3pcs
Note: the above technical parameters in the ambient temperature of 25 ℃, relative
humidity is not more than 85%, no sample load conditions, the precision of 0.1 ℃
standard mercury thermometer measured head end in the geometric center working
chamber (mercury).
III.Summary of structure
Vertical series drum wind drying oven baking varnish outer shell adopts the high quality
steel plate surface, the working chamber is made of stainless steel plate, interior is
equipped with the racks, middle layer filling superfine glass wool insulation.
Adopt double-layer tempered glass door, the door is the material heated in the cabinet
can be observed clearly. Studio and joint with heat resistant silicon rubber sealing ring,
the door is in place to ensure that the studio and the seal between the door. Drying oven
power switch and temperature controller in case positive.
The heating temperature in the cabinet system is mainly composed of high-quality motor,
electric heater with centrifugal impeller, suitable air duct structure and temperature of
temperature controller. When switch the oven on, the motor is running at the same time,
is located in the bottom of the box electric heaters that are directly related to the heat by
air duct discharge upwards, after dry goods suction fan in the working chamber to
continuously circulation, thus make work indoor temperature to achieve uniform.
Cabinet is equipped with leakage protector.
IV.Method of use
1.. the items placed in drying oven drying processes, the door is closed.
2. The power switch to "1", the power switch, screen has a digital display.

3
3. According to the temperature controller instructions, set up to working temperature and
working hours (working time can not set).
4. The device will automatically run to working conditions, shut off the power switch after
use, take out the goods.
（Does if the operating temperature is too high (generally higher than 70 ℃), be
sure to wait for equipment cooling will remove items later）
V.1.Panel Instructions
Definitions of symbols:
1．【MAIN】：Only in normal state(not setting mode),this symbol appears
2．【SET】：Only in setting mode , this symbol appears
3．RUN：This symbol always appear unless the timing program is over.
4．STOP: This symbol appears to show you timing program is over.
5．【AT】：This symbol twinkles only when you start an Auto-tuning procedure
6．ALM!：This symbol appears to show you over-temperature alarm
7．HEAT：This symbol appears or twinkles to show you the heater is working.
2. Operation and using
1) When the controller is switched on, display windows show the version number
and the value of temperature range for 3 seconds, then it starts running.
2) “◄” button: In the setting state, click on the button to shift the set value.

4
3) “▼” button: In the setting state, click on the button to reduce the set value. If you keep
pressing on the button, the set value will reduce continuously.
4) ”▲” button: In the setting status, click on the button to increase the set value. If you
keep pressing on the button, the set value will increase continuously. In the Normal status,
click on the button to open or close the backlight lamp.
5) In the setting mode, If no button is pressed within 60s, the controller will automatically
return to normal display.
6) Temperature and time setting
No timing function
Press the “SET” button in the non-set state, windows display the prompt “SP” and
temperature set value. Using the “SHIFT”、”DEC” and “inc” buttons, user can modify the
settings to the desired value, then press the “SET” button again, controller will return to
the normal display, the setting value will be saved automatically.
With timing function
Press the “SET” button in the non-set state, windows display the prompt “SP” and
temperature set value. Re-press the “SET” button, windows display the prompt “ST” and
time set value. Press the “SET” button again, controller will return to the normal display,
the setting value will be saved automatically.
When the time is set to “0”, it indicates the timer is inoperative, the controller will run
continuously. If there is time set, the under window of controller will display temperature
setting value or the running time according to the value of “ndt” in Parameters table 2.
When display the running time, the unit decimal point is lit, Start timing when the
measured temperature reaches to the setting value, When the runtime is over, the under
window of controller will display “End”, the buzzer will sound for 60s, it can be muted by
pressing any button, press the “RST” button for 3s at this time, the controller will restart.
7) When Over-temperature alarm, the buzzer beeps continuously, "ALM" warning light is
lit.

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8) When the buzzer sounds, press any key to mute.
9) If the controller upper display window displays “----”, said temperature sensor or the
controller itself fails, please carefully check the temperature sensor and wiring.
3. Auto-tuning of PID
Use auto-tuning function when the temperature control is not good.
In the non-set state, press the “AT” button for 6s,the window displays ‘AT’ and
‘oFF’,change ‘oFF’ to ‘oN’ by ‘Inc’ or ‘Dec’ button,then the controller will run the
auto-tuning program, the “AT” symbol flashes, after auto-tuning end, the light stops
flashing, parameter value is saved automatically. In the auto-tuning process, press the
“AT” button for another 6s, the controller will stop the auto-tuning program.
In the auto-tuning process, the “SET” button is invalid, the under window always
displays temperature set value.
Action please: the temperature is not precisely controlled when you start an
auto-tuning program,there must be over-temp situation,please take out your stuffs from
the oven before auto-tuning.
4. Internal parameters settings
In the non-set state, Press the “Set” button for 3s, controller will display the password
prompt “Lc”. Adjust the password to the required value, then press the “Set” button again,
it will run into the internal parameter setting state. If press the “Set” button for another 3s,
it will return to the running state, the setting value will be saved automatically.
Parameter table 1
Parameter
prompt
Name
Instruction of the function
(Setting
range)
factory
set value
Lc-
Password key
When Lc=3, enter the next parameters.
0
ALH-
Over-temp
If “SV>(SP+ALH)”, the “ALM” light turns on.
(0～

6
alarm
The buzzer sounds and the heating output
turns off.
100.0℃)
20.0
ALL-
Under-temp
alarm
If “SV<(SP-ALL)”, the “ALM” light flashes,
the buzzer sounds.
(0～
100.0℃)
0
P-
Proportional
band
Adjustment of proportional function.
(1～
400.0℃)
50.0
I-
Integration
time
Adjustment of integration function.
(1～
2000S)
700
d-
Differential
time
Adjustment of differential function.
(0～
1000S)
350
T-
Control cycle
The temperature control cycle.
(1～60S)
5
Pb-
Zero point
adjust
When the zero error comparatively larger, to
update this value should be needed.
Pb= actual value – measure value
(-12.0～
12.0℃)
0
PL-
Full point
adjust
When the full point error also comparatively
larger, to update this value should be
needed.
PK=1000×（actual value – measure value）/
measure value.
(-999～
999)
0
Addr
Address
The communication address. invalid
(1～32)
1
Loc
Setting lock
0:you are allowed to alter the set value of
temperature and time;
0(0~1)

7
1:the set value of temperature or time is not
allowed to alter
Parameter table 2
Parameter
prompt
Name
Instruction of the function
(Setting
range)
factory
set value
Lc-
Password key
When Lc=9, enter the next parameters.
0
ndA-
Temp alarm
mode
0: With over-temp alarm only.
1: With over-temp alarm and
under-temp alarm at the same time.
(0～1)
0
ndt-
Timer mode
0: No timer function.
1: The timer get to work as soon as the set
temperature value is achieved..
2: The timer start to work as soon as the
instrument get to work.
(0～2)
1
Hn-
Timer unit
0: Minute.
1: Hour.
(0～1)
0
SPD
Timer
parameter
When measured value of
temperature >SPD+set value of
temperature,timer get to work
(0.1～
100.0℃)
0.5
SPT
Constant
temperature
tip time
In timing mode(set value of temperature is
achieved),the buzzer reminds you when the
tip time you’ve set is achieved.
(0～
9999S)
0
EST
Tip after timing
When timing program is over,the buzzer
reminds you as soon as the tip time you’ve
set is achieved
(0～
9999S)
0
EH-
Timer end
0: Continue to maintain the constant
(0～1)

8
mode
temperature when the running time is over.
1: Stop the temperature control when the
running time is over.
0
ndo-
Switch-output
0: when timing program is over
1: when over-temperature alarm occurs
2:when the timer starts to work
(0～2)
0
SPL-
Minimum
set point
The minimum temperature set point.
(-50.0～
50.0)
SPH-
Maximum set
point
The maximum temperature set point.
(0～
400.0)
Parameter table 3
Parameter
prompt
Name
Instruction of the function
(Setting
range)
factory
set value
Lc-
Password key
When Lc=27, enter the next parameters.
0
FC
Temperature
unit
0:Centigrade
1:Fahrenheit
(0~1)0
5、Wiring

9
VI.Matters needing attention ：
1. The drying oven shell must be effective grounding, to ensure the safety in use.
2. The drying oven should be placed in good indoor ventilation, around its do not place
flammable items.
3. The drying oven no explosion-proof device, and may not be in the inflammable and
explosive goods and dry.
4. Items placed in the not too crowded, especially surrounding the temperature sensor,
must make room, hot air circulation.
5. Box should be always kept clean inside and outside, not for a long time should be set
good plastic dust cover, put in the dry room.
6. Use of the abnormal phenomenon, please cut off the power supply and promptly get in
touch with our company!
VII.Fault handling：
phenomenon
principle
Deal
No resource
No power supply socket
Replace the socket
Good is not plugged in or
disconnected
Insert the plug or good pick up
line
Fuse open
Change the fuse
The power switch is not
closed
Close the power switch
The temperature in the
cabinet does not rise
Set temperature low
Adjust the set temperature
Electric heater is bad
In electric heater
Temperature controller is bad
Change the temperature
controller
The temperature sensor cable
Tighten the sensor connecting

10
is loose
nut
The great error in the
set temperature and
the temperature in the
cabinet
Temperature sensor is bad
In the temperature sensor
Temperature is out of
control
Temperature sensor is fixed
Fixed temperature sensor
Temperature controller is bad,
silicon controlled rectifier
In the temperature sensor,
silicon controlled rectifier
VIII.Packing list：
No.
Item
Qty
1
Thermostatic drum wind
drying oven
1
2
Shelf
2
3
Fuse core
1