Networkable, Low-Voltage, Bidirectional,
Thermo-Electric, Proportional and Integral (PI), 12-Bit,
Temperature Controller (1 Load for Heating and Cooling) with Two RS232
LCD Ports, Integrated Heat-Sink, 750Hz PWM
Low-Voltage Thermal Electric (TE) Controller is specially designed
to operate at low DC supply voltage levels (3V to 20V range) and the
H-bridge fully turns on at 3V.
Networkable 9600-Baud RS232
Input/Output Control Port:
For Set-Temperature and control
parameter Input; and for
Measured Temperature and Control parameter Output . All control
parameters are stored in nonvolatile memory. Up to 61 Boards can be interconnected
to form a 3-wire Local Area Network, LAN.
PI Temperature Control:
Proportional and Integral (PI) Temperature Controller
in the -500C to +1200C Range with 0.0650C steps
on 1 Load.
Efficient H-Bridge with PWM: 750Hz Pulse-Width Modulation (PWM) is used to perform
the heating and
cooling function (at the same time) on a Peltier type (TE) cell,
functioning as a bidirectional heat-pump.
One Digital Temperature Sensor:
Digital Temperature Sensor with 0.06250C
and 1/20C Accuracy
-100C to +800C Range, and approx.
-550C to +1250C Range.
Temperature Sampling Rate:
The temperature is sampled at approximately 1Hz rate and the
control-loop/display is updated with this same rate.
An Optional RS232 LCD Port:
For Set and Measured Temperature Display.
Switch on J1:
open switch (or an Open Collector npn Transistor) can be connected
to jumper port J1 (as shown below), J1 Open=Normal operation, J1
Short=Load (TE Cell) is open.
(from pin +C to pin - P):
9V to 30V DC, and for VP (from pin +P to pin -P)
3V to 20V, both unregulated DC voltages. For high-voltage
applications (9V to 20V) a single DC power supply can be used by
connecting pin +P and pin +C together.
98.5% typical, at 20V and 10A
Max Load Power: 200W at 20V, 10A.
Max Operating Temperature:
with the Integrated
Aluminum Plate Heat Sink Heat Sink, as shown.
Power Semiconductors: Four 60A Hex-MOSFETs
Overall Dimensions: 4.0" x 3.3" x 1.4" (102 x
84 x 34mm).
Components Type: 100% Solid State, NO
Isolated Control Signals
Filter Capacitors, Voltage Transient Suppression (VTS)
Bicolor LED Indicator, (Red=Hot, Green=Cold)
Si25NeTEPITC1-12B-20V-10A is a 20V at10A,
Networkable, Thermo-Electric (TE), Proportional and Integral (PI)
Temperature Controller that perform the heating and cooling function (at the
same time) using 1
Low-Voltage type Peltier type (TE) cell, functioning as a
bidirectional heat-pump. The fundamental components of this controller are: a
12-Bit digital temperature sensor; an efficient low
voltage (3V to 20V DC) H-bridge that controls the TE cell current (in
the 0 to +/- 10A range) using 750Hz Pulse-Width Modulation (PWM); and a
networkable microprocessor that controls the temperature, stores the selected
network parameters in a nonvolatile memory and drives the H-bridge.
This H-bridge is specially designed to operate at low DC
supply voltage levels (3V to 20V range) and fully turns on at 3V.
The temperature is measured with a 12-bit digital sensor and the process is PI
controlled with 0.06250C steps in the -500C to +1200C
range. By PI control, we mean that the amount of correction used in
the control-loop is proportional to the difference and the Integral of the
difference between the set and measured temperature values. A single DC power
supply (in the 9V to 30V and 0A to 20A range) is required to operate this
controller. Two proportional-band parameters are used “c”= 001,...199 for
Cold band, and “h”= 001,...199 for Heat band. One step change in the band
parameter represents a 1 degree C change. Two control bands are used because the
TE cells are more efficient in heating mode than in the cooling mode. These
proportional control bands are centered at the set-temperature value; and a
smaller band value represent more aggressive proportional control. Full heating
or cooling TE-cell power (100% PWM) is used when the measured temperature is
outside of this selected band; and reduced TE-cell power (100% to 0% PWM as
specified by the PI control) is used inside this band. The integral gain
“i”= 001,...199 controls the contribution of the integrator to the total
PI control sum. Larger integral gain values represent higher integral
contribution (“i”=199 represents 100% contribution). The integrator is
reset to zero each time a new set temperature is selected and its growth is
limited to prevent excessive integral contribution ( “integral windup”). A wide
range of thermal loads can be efficiently controlled with proper control
parameter selection. The temperature overshoots and
oscillations (“hunting”) are limited to approximately + or - 0. 50C.
Control parameter selection and PI tuning are defined in the
network section given below. The temperature is sampled at approximately
1Hz rate and the control-loop/display is updated with the same rate.
A Typical Application of the
12-bit, closed-loop, Proportional and Integral (PI) temperature control
application, the Set-Temperature is adjusted by command strings derived from a
Personal Computer (PC) using the Microsoft “Hyper Terminal” program (or
any-other ASCII controller) operating at 9600 Baud, 1 start-bit, 8 data-bits, 1
stop-bit, No parity-bit. The Peltier type Thermo-Electric (TE) cell is
functioning as a bidirectional heat-pump; operating with 3VDC (unregulated) at
10A max. The
Low-Voltage TE cells can be purchased from
TE Technology, Inc. WEB:
www.tetech.com. The temperature of the enclosed and insolated Hot/Cold
Environment is measured with the Dallas Semi. DS18B20 (in TO-92 casing) Digital
Si24DTsens-Spec1-DS18B20.This sensor can be purchased from Signal
Consulting, LLC as
Si24DTsens-12B (DS18B20 with 12” leads and connector). The optional LCD
module can be ordered from Signal using the part number of
Si14LCD2L16CH-4PC (2x16 display with 16” cable and 4-pin connectors,
and with back-light). Warning: The connecting wires
to the Load and the Power Supply must be heavy gage copper wire (#12 AWG or
heavier) to handle the rated current level. In addition, these heavy gage wires
act as a heat sink, protecting the board from overheating.
Command Format and Local Area Network (LAN)
for the Si25NeTEPITC1-12B
Each board has a unique,
8-bit, ASCII, none-volatile, Node-Address ranging from 1….9, A..Z, a,…z (
or a total of 61 Units can be networked).The address can be changed by a LAN
command (the factory default address is 1). The board uses a modified
version of the RS232 serial-data communication standard, where the
output-voltage (on pin I2, CN6) ranges from 0 to +5V (rather than the
usual -12V to +12V). In addition, this output pin is normally an open circuit
and it will only output a serial TTL binary bit-stream when properly referenced
by its Node-Address. The serial data input-voltage (on pin I1, CN6) has
the standard range of -12V to +12V. The serial data-format is: 9600 Baud Rate, 1
Start-Bit, 8 Data-Bits, 1 Stop-Bit, and no Parity-Bit. These features allow the
creation of a Local Area Network (LAN) with up to 61 nodes (boards).
A typical 3-wire LAN
with “Star Topology” is shown below. Note that the control lines (G, I1, I2)
with the same name are connected together (or the boards are connected in
parallel) and driven by an ASCII controller (or PC), equipped with
an RS232 serial port, operating at 9600 Baud rate.
Click on the "Buy this Product"
Button or the Blue Links to
BUY these Accessories
Si25NeTEPITC1-12B-20V-10A, it is recommended to buy one
Digital Thermometer and one or more Network Accessories.
Si24DTsens-12B , 12-bit Digital Thermometer (
-550C to +1250C Range, in 0.0650C
12" leads and 3pin Molex Connector.
2 Line by 16 Character LCD with 12" long cable and 4-pin
1m long Network Cable Assembly with 9-pin female DB9
1m long Network Cable Assembly 9-pin female DB9
connector and a “Junction-Box” with 5 Phone Jacks.
1m long Network Cable Assembly with 6P4c Phone Plug
connector and a “Junction-Box” with 5 Phone Jacks.
We usually ship in 2-3 business
All Products Are Proudly Made in the USA