SMC Networks HEC002-A5, Operation Manual

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Unit Overview
HEC002-A/HEC006-A 4-4
4.6 Functions
4.6.1 Auto tuning
This function sets the values necessary for the control system such as PID (proportional band, integral
time, derivative time and ratio of cooling/ heating gain) automatically.
4.6.2 Offset function
This function controls the temperature slide by an offset value from set point temperature. The range of
offset is -9.99 to 9.99

C. When the circulating fluid is carried to the target object, a certain deviation
occurs between the temperature before the object and the setting temperature of the product due to the
influence of ambient temperature on the piping. In this case, if the deviation is input as the offset value,
the temperature of circulating fluid just before the object can match with setting value.
Internal sensor value for alarm does not include the offset value.
4.6.3 Learning control function
This function lets the product measure the temperature of circulating fluid flowing before temperature
target object by an external temperature sensor and adjusts the offset function automatically to the set
value at a certain sampling interval. The external temperature sensor needs to be prepared separately
by the customer.
4.6.4 External tune control function
This function makes the temperature of circulating fluid consistent to the external (ambient) temperature
all the times. This function lets the product measure the temperature from a temperature sensor
mounted in the customer preferred location, then it adjusts the temperature of the fluid automatically to
the temperature detected by the sensor. The separate temperature sensor needs to be prepared
separately by the customer.
4.6.5 Temperature sensor fine control function
This is a function to finely control the measurement temperature of the control sensor within the range of
-9.99 to 9.99

C separate from offset function. Control sensor can be corrected by inputting difference
(calibration value) between temperature of standard and that of control sensor.
Internal sensor value for alarm includes the fine control value.
Internal sensor value for alarm = Internal sensor value
– Fine control value
4.6.6 Setting value memory function
(Function that backs up with EEPROM)
This function backs up all the manually set values to nonvolatile memory (EEPROM). Even if the power
is turned off the set values are saved and will be restored at power on.
4.6.7 Upper/ Lower Temperature Limit Alarm Function
This function raises an alarm when temperature of the circulating fluid is out of allowable upper and
lower range. When the alarm is raised, WRN is indicated on LCD. If circulating fluid temperature returns
to within allowable upper/ lower range, this alarm is automatically canceled. The allowable upper and
lower range of temperature can be set between 0.1 and 10

C.