Networkable, Thermo-Electric (TE), Proportional and Integral (PI),
12-Bit, Temperature Controller (1Load, Heat and
Cool) with an RS232 Serial Control Port, Integrated Heat-Sink,
Three 12-Bit Digital Sensors (2 Auxiliary),
and with a Serial LCD Ports, 750Hz PWM
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
A 12-Bit Digital Temperature with 0.06250C
and 1/20C Accuracy
-100C to +800C Range, and approx.
-550C to +1250C Range.
sensors (DTS2, DTS3):
12-Bit Digital auxiliary sensors (same as DTS1) reports the
temperature readings at any remote locations in the -550C
to +1250C range with 0.06250C precision and
Temperature Sampling Rate:
The temperature is sampled at approximately 1Hz rate and the
control-loop/display is updated with this same rate.
An 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) 9V to 50V, both unregulated DC voltages. For low-voltage
applications (9V to 30V) a single DC power supply can be used by
connecting pin +P and pin +C together.
98.5% typical, at 50V and 20A
Max Load Power: 1000W at 50V, 20A.
Max Operating Temperature:
with the Integrated
Aluminum Plate Heat Sink Heat Sink, as shown.
Power Semiconductors: Four 90A 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)
Si25NeTEPITC1-12B3S-50V-20A is a 50V
20A, Networkable, Thermo-Electric (TE), Proportional and Integral (PI)
Temperature Controller that perform the heating and cooling function (at the
same time) using 1 Peltier type (TE) cell, functioning as a bidirectional
heat-pump. The fundamental components of this controller are: three
12-Bit Digital Temperature Sensors; sensor DTS1 in the control loop and
two Auxiliary sensors (DTS2, DTS3); an efficient high-power H-bridge that
controls the TE cell current (in the 0 to +/- 20A 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. The two Auxiliary sensors (DTS2, DTS3), these can
report temperature readings at any remote locations in the -550C to
+1250C range with 0.06250C precision and approximately 1.00C
temperature of the enclosed thermal-zone (measured with DTS1) 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.
A Typical Application of the
12-bit, closed-loop, (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. The TE
cells can be purchased from:
www.customthermoelectric.com/. A simple unregulated DC power supply
is shown below, wide variety of linear and switching power supplies can also be
used with this board; click on
www.mpja.com to find these supplies. The temperature of the enclosed
Hot/Cold Environment is measured with the Dallas Semi. DS18B20 (in TO-92 casing)
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 12” 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)
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, CN5) 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, CN5) 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.
on-board microprocessor provides the bus arbitration, required to avoid data
collisions on the 3-wire LAN bus. The
Si..Ne.. boards can be arranged in many
Local Area Network (LAN) topologies: Star, Daisy-Chain, etc. You may
create your own network or you may order one or more of
the Network Cable Assemblies listed below. Before you build your
network, click on this blue link and read this Application
Note: Sig-Note on Configuring a LAN-2 .
Click on the "Buy this Product"
Button or the Blue Links to
BUY these Accessories
Si25NeTEPITC1-12B3S-50V-20A, 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