TE Technology TC-24-25, Руководство по эксплуатации

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General Description
The TC-24-25 RS232 is a bi-directional control for independent thermoelectric coolers or in conjunction
with auxiliary or supplemental resistive heaters for both cooling and heating applications. The H-bridge
configuration of the solid state MOSFET output devices allows for the bi-directional flow of current
through the thermoelectric coolers. Highly efficient N-channel output devices are used for this control
mode.
This controller is programmable via an RS232 communication port for direct interface with a compatible
computer. The easily accessible communications link permits a variety of operational mode
configurations. Field selectable parameters or data acquisition in a half duplex mode can be performed.
This controller will accept a communications cable length in accordance with RS232 interface
specifications. The supplied software is compatible with Windows 95/98/XP/NT.
Once the desired set parameters are established, the TC-24-25 RS232 can be disconnected from the
computer, and it becomes a unique, stand-alone controller. All parameter settings are retained in non-
volatile memory.
The user friendly, communications software requires no prior programming experience to establish
operation. A command set is provided for qualified personnel to program a software interface or use as
an embedded control.
Mechanically, the control printed circuit board is mounted to a metal bracket that is suitable for either
horizontal or vertical orientation. Input and output connections are accessible via screw type terminal
strips and fast-on terminals.
Technical Description
The TC-24-25 RS232 is capable of operating from an input supply voltage of (12 to 28) VDC, common
to many available thermoelectric coolers. The self-contained MOSFET output devices deliver load
currents from (0.1 to 25) A. (NOTE: consult appropriate installation instructions for power supply and
heat sinking requirements for high current operation). This unit will control total load power up to 680
W with a finite temperature resolution of 0.1 °C or 0.1 °F.
The output signal to the thermoelectric cooler is pulse-width modulated and can be set for either 675 Hz
or 2700 Hz operation. Pulse-width modulation (PWM) averages the amount of energy provided to the
module and reduces the extreme temperature excursions that are experienced with a thermostatic control
system. This tends to extend the life and reliability of the thermoelectric devices. The PWM control
scheme affords control accuracy to within ±0.1 °C or ±0.1 °F at the control sensor.
The controller tuning structure allows designation of a variety of control features:
1) The Computer Set Value provides for manual control of the output from 0% to ±100% of load power.
2) Proportional bandwidth (P) in degrees, Integral reset (I) in repeats per minute, and the Derivative rate
(D) in minutes may be configured for P, PI, PD, or PID control.