TE Technology TC-720 - Manual (Page 49)

magnitude of the voltage to the thermoelectric device is controlled by the analog output signal and a
programmable linear-output power supply. Temperature control is achieved in the following manner:
a) The analog output signal on JP2-5 is used to send a 0 to 10 Vdc analog control signal to an external
linear power supply. This 0-10Vdc signal corresponds to 0 to 100% output power, and is independent
of the required output polarity (it is magnitude only). See also the options in the OUTPUT BOX for
additional details where the maximum output signal can be reduced to match the requirements of
the power supply you intend to use.
NOTE: The analog output is always present, regardless on if the controller is in ANALOG OUT mode or
not.
b) The linear-output programmable power supply uses this 0-10V control signal to adjust its output from
0 V to its full-scale voltage. This creates a high-power, variable analog voltage for the
thermoelectrics.
c) The voltage generated by the linear-output power supply is fed back into controller at JP7-3 and
JP7-4.
d) The polarity of this voltage is then kept positive or reversed depending on if heating or cooling is
needed (H-Bridge output is +100% or -100%)
e) The voltage is sent to the thermoelectric device at terminals JP7-1 and JP7-2. Thus, full linear control
with both magnitude and polarity is accomplished.
2. RAMP/SOAK—the controller will follow a sequence of set points defined by the ramp/soak profile. See Ramp/Soak
Configuration below for further details.
3. PROPORTIONAL+DEAD BAND—the controller will provide linear power output between two temperatures in both
heating and cooling mode. A dead band is allowed between these heating and cooling points where no power is
sent to the thermoelectric devices. This is useful with outdoor enclosures that have a broad operating
temperature range and only need cooling or heating at times of extreme temperatures. Otherwise, when the
enclosure temperature is within the pre-defined temperature range, output power can be off in order to save
energy. See PROPORTIONAL+DEAD BAND CONFIGURATION below for further details.
49