5．OPERATION
5.1 Sequence to pick up the functions of the instrument
Power on
Upper row displays code
（
Sn
），
lower Row
displays type No. （Display input type）
Upper row: Input high limit, lower row
input low limit(Display input Lange) Automatically turn over after 4 seconds displaying
Upper row displays process value, lower
Automatically return over when not press any key over 1 minute
row displays set value(Standard mode)
Press function key
Upper row displays setting code (SP,St), lower row
displays set value
（
Update the setting mode
）
Press function over 4 seconds
Upper row displays function code (AL
…), Lower row displays
control parameters（
Changing the control parameters
）
5.2 The detail description for every function
If upper row displays ―OVER‖ the sensor is in open circuit or the input signal excesses the range of measurement.
The method for changing set value:
Press
/set key the upper row displays SP. Pressor key，the low row displays the needed
value. Again press
the upper row displays st key. Pressor key, the lower row displays the timing
time needed. Again press
key, the instrument return to the standard display mode.
Timing function
When the value of St is setting to zero, the timing function is canceled. Otherwise when the
value of St is not setting to zero the timing function is available.
When the power is turned on, the timing function starts . In case of achieving the setting timing the heating
output is close. and the buzzer sounds four times to notice the operator.
But the refrigeration output is working continuously. When the system is starting with auto tuning, the timing
function is also canceled. When the auto tuning process is completed, the
timing function would start again. During the operating period of the instrument, it is allowed to update the
value of St online, and the time passed can be memorized and the instrument will operate the updated timing
time. When the updated time is less than the passed accumulative
time, the heating output close immediately, the buzzer sounds 4 times. The refrigeration output is working
continuously.
The method for changing control parameter:
After press
key over 4 seconds, find LK. Then press or key to the lower displayer display 18.Again
press the
key to find the symbol character for the needed parameter. Through press the or key till the
high row displays display the parameter needed is reached. Some parameters may be setting at once. Press the
key over 4 seconds the instrument returned to
the standard mode. If no key is press down the instrument return to its standard mode after 1 minute.
5.3The function of the controllerAuto-tuning
After pressing /TIME key, The instrument displays the time have operated.
After pressing /AT key 20 seconds the AT indicator flashes and the auto-tuning press starts; after the end of
auto-tuning the AT indicator then be turned out. A set of PID parameters can be got automatically for overcoming
temperature overshoot. The controller operates according to this set of PID parameters.
is working continuously.
In the period of auto tuning, if press /AT key beyond 20 seconds the AT indicator turn out and the auto tuning
process is canceled. The instrument operated according to the original PID parameters.
Following table lists the function parameters
0～Full Range
0.0～Full Range
When temperature is beyond SP+AL, the ALM
indicator turn on. The buzzer sounds and the
heating power turn off.
Refrigeration
control setting
0～Full Range
0.0～Full Range
When the temperature less than SP+COL, the
refrigeration point is turn on to drive the
compressor.
1～Full Range
1.0～Full Range
Proportional control action . if P is larger then
the gain of system is lower. it only use on the
heating side.
Integrated time constant. I larger, then the
integrated action is smaller.
Derivative time constant. D larger, then the
derivative action is also larger. D can overcome
overshoot. I=0 and D=0 is called half
proportional control.
Overshoot Control
(re-setting)
At on-off PID control, the value of Ar is a
constant which equals 1.5~2 times of the ratio of
on time to the on-off period in the equilibrium
state. In the half proportional control, the Ar
equals coefficient/P.
For the thyristor output it is about 1 ～3
seconds. For those equipment that the
superfluous power provided is comparatively
larger, select larger T would decrease the stable
error caused by PID control.
Zero point adjust
(intersection)
When the zero error comparatively smaller and
the full point error comparatively larger, to
update this value should be needed. Ordinary for
Pt100,updating this value is rarely needed.
Full point adjust
(intercept)
When the zero error comparatively larger and
the full point error also comparatively larger, to
update this value should be needed. PK=4000×
（setting value –actual value）/actual value. For
Pt100 adjusting this value is need at first time.
Refrigeration
control Time
delayed
When measuring value reaches its alarm value,
the alarm relay output will be delayed this time..
The decimal
Point setting
When D=0 the display resolving power is 1℃
and when DP=1 the display resolving power is
0.1℃
Adjusting rH can make the instrument range
equals 0～rH(℃)
when Lk=18 the parameters listed above then
the above parameters can be updated.
