Receiver Circuit

Digital Remote Thermometer circuit with very high accuracy temperature measurement features are set using the IC package numbers

Receiver Module Functional

LM35 (Linear temperature sensor IC) through a power amplifier and voltage change as a form of high frequency. To signal through the AC power cord.
For the receiver circuit and display module will receive the high frequency AC power cord and decode out to be the actual temperature figures with digital IC No. CD4553 Three-digit BCD Counter IC) and IC-CD4511 (BCD-to-7-Segment Latch / Decoder / Driver IC).

 Electronic Part List

Receiver Module
R1   100K 1/4W
C1,C2  47nF 400V
R2  1K 1/4W
C3,C7  1nF 63V
R3,R4,R6-R8  12K 1/4W
C4  10nF 63V
R5  47K 1/4W
C5,C6,C10  220nF 63V
R9-R15  470R 1/4W
C8  1000uF 25V
R16  680 1/4W
C9  100pF 63V
D1,D2,D5  1N4148
D3,D4  1N4002
D6-D8  Common-cathode 7-segment LED mini-displays
IC1  403
IC2   4518
IC3  78L12
IC4  4017
IC5  4553
IC6  4511
Q1 BC239C
Q2-Q4  BC327
 
L1  Primary (Connected to C1 & C2): 10 turns
Secondary: 100 turns
Wire diameter: 0.02mm. enameled
Plastic former with ferrite core. Outer diameter: 4mm.
 
T1 220V Primary, 12+12V Secondary 3VA Mains transforme

Remote Module Functional
    The frequency pulses from the wall and safely isolated by C1, C2 and L1 are amplified by Q1, diodes D1 and D2 of the peak limit his admission. The pulses are filtered by C5, IC1b square, divided by 10 in IC2B and sent for final countdown clock input of IC5. IC4 is the time base generator: it provides IC1b and reset pulses to the making and IC5 locks and opening time of IC5 at 1Hz frequency. It is powered by a 5Hz square wave obtained from the frequency 50Hz sector Retrieved from T1 secondary, squared and divided by 10 in IC1C IC2A. IC5 readers across the cathodes scenes Q2, Q3 and Q4 with a rate determined by frequency multiplexing C7. Readers also shows three anodes in parallel by the BCD to 7 segments decoder IC6. In summary, the input pulse power on, say, 2kHz frequency be divided by 10 and displayed as 20.0 ° C

Remote Circuit

Electronic Part List

 

Remote Module
R1,R3  100K 1/4W
C1  220nF 63V
R2  47R 1/4W
C2  10nF 63V
R4  5K 1/2W Trimmer Cermet
C3  1uF 63V
R5  12K 1/4W
C4,C6  1nF 63V
R6  10K 1/4W
C5  2n2 63V
R7  6K8 1/4W
C7,C8  47nF 400V
R8,R9  1K 1/4W
C9  1000uF 25V
D1  1N4148
IC1  LM35
D2,D3  1N4002
IC2  LM331
D4   Red LED
IC3  78L06 
Q1  BC238
Q2 BD139
 
L1   Primary (Connected to Q2 Collector): 100 turns
Secondary: 10 turns
Wire diameter: 0.02mm. enameled
Plastic former with ferrite core. Outer diameter: 4mm.
 
T1   220V Primary, 12+12V Secondary 3VA Mains transformer
 

High temperature warning circuit

The circuit is a low temperature regulator, supervisor, warns us about global warming. Temperature control is done by the thermistor TH1, which is a negative factor. The resistance varies between 10KO at 25 ° C and about 1KO at 94 ° C. The trimmer TR1 regulate the exact temperature at which the Q1-2, connected as a Darlington, lead me, making the relay K1 to close and IZ, sound. The alarm is activated when the temperature is greater than the default. The thermistor should be located away from the rest of the circuit, so as not to risk from the heat. The power circuit is battery 9V, but if it is mounted in a fixed position, then we can supply with a constant voltage power supply. The relay contacts can be connected load which we, as a bulb, another circuit, etc. It can also add an LED, if we are to sign and visual stimulation. The adjustment is done by immersing the thermistor TH1, in the water which we know the temperature (contacts should be well insulated so we do not have short circuit) and adjusting the trimmer until the circuit is excited. The cable connecting the circuit with the TH1 must be shielded.

Part List
R1= 820 ohm
R2-3= 1Kohm
C1= 220uF 16V
TR1= 2.2Kohm Trimmer D1= 5.6V 0.5W Zener
D2-3= 1N4148
Q1-2= BC550C
TH1= Thermistor 10Kohm at 25° C 
 K1= 6V 200 ohm Relay
BZ1= Buzzer
S1= 1×2 Switch
BATT= Battery 9V or external supply

Application
This circuit is designed not only setting a detection of high temperatures, but can also be changed to be set on the detection of low temperatures in some areas. It can be used for refrigeration, walk-in refrigerator or freezer and other environments that are sensitive to temperature. Some integrated circuits high-temperature alarm modules will be used in motor vehicles to the profession in which the temperature element senses a temperature very dangerous in the interior of a motor vehicle, and encourages the employment sensor detects the presence or determine the absence of an occupant. In the absence of the inhabitants, the sensor is that after a period during which an audible alarm is activated to provide the attention to the motor vehicle in the presence of an occupant. This type of alarm can be reset with a key.

Take a temperature alarm can be advantages such as protection of valuable equipment by high temperature, low temperature, high humidity or sometimes provided. Other programs of high temperature can be used to protect against loss of or against the air conditioning system for heating off. Instead, the program for low-temperature failure of the heating system be used to prevent frozen pipes. The alarm can also reduce downtime, get a phone call and the notification of a possible power failure or failure before damage occurs in one unit.

The Darlington can be used in the circuit are also used as an important component in a switching device, while high power Darlington transistors can be used in emergency power and control circuits for AC and DC motor control. These applications make Darlington suitable for switching large currents in high-power circuits.

Terminology
Thermistor – a kind of resistance can be used as a temperature sensor, showing a large change in resistance proportional to a small change in temperature due to the composition of the semiconductor material
BC550 – General purpose NPN transistor at low voltage and low power for low noise stages in audio frequency used
Declaration of the circuit
The temperature can be adjusted through the design of this circuit can rise and a sample of the warning at a high temperature. The temperature control begins with the thermistor TH1, which contains a negative factor. Since this component has a resistance proportional to temperature is important, changes the resistance when a 10K ohm resistor is generated ate 25 ° C, while the 1K Ohm resistor produced at 94 ° C. to a specific value on the temperature, a trimmer TR1 for a value of 2.2 K ohms is used when the transistors Q1 and Q2 are used to define. This gain to produce bipolar transistors forming a Darlington a very high current is much higher then taken individually each transistor. This is possible if the current is amplified by the first transistor further reinforced by the second transistor. The total increase is equal to the two individual gains multiplied together.

A Darlington is designed so that the collectors of two transistors are connected together and the emitter of the first transistor is directly connected to the base of the transistor coupled to the second or exit. The base current of the output transistor is equal to the current emitter of the transistor input. If you can use different transistors form a cascading and the coefficient of current gain will be very high as it is a product of the current gain of each transistor.

If the Darlington in this circuit, which causes the relay K1, thus triggering the buzzer sound close by the temperature increase, which leads generate more than the predetermined value. to avoid the position of the thermistor must be far enough away from other components of the circuit which inhibits its temperature. The circuit can be provided with a 9V battery for portability, but its own power supply, the circuit would be in a permanent position. A load such as a lamp or an LED can also be connected to the relay contacts, to produce a clear signal or notification of the occurrence of overheating. Because the circuit is well insulated, the thermistor of the circuit with a galvanized wire are connected to the water to cool or be immersed to restore the sensitivity and does not cause short circuits. This regulates the trimmer.

Thermostate cicuit

A Thermostat that is adaptable for many applications or your electronic project.

The probe can be any number of diodes but 4 to 6 is buite reasonable, RX is set for an appropriate value
and RI is the fine adjustment to set the temperature.
R2 provides hysteresis which is a dead spot between on and off RL can be any 12 Volt load.
Ground unused input  pins on the 4050.
since the probe is near ground potential it can be used underwater if coated with a litter epoxy.

temperature regulator circuit

    For best efficiency,make good thermal contact between the 40 ohm resistor,the TIP 122,the 3 diodes and the temperature controlled entity , the components all give off heat.

We have some minor changes to the draft Roy. Roy A 4.7V zener is used in its original design and a resistor network, a range of operating temperatures of 188 degrees Kelvin to 243 Kelvin degrees C or -85 to -30 C.

   This is fine in Cryocam Roy, but I’m afraid that many of our camera cookbook may not be able to reach a maximum temperature of Roy. That and the fact that related to the Zener 4.7V difficult to replace me with Roy Z 5.1V zener with more accessible. This diode is available off the shelf at Radio Shack. I supply the resistor network on a range of 190 K to 270 K or -83 C to -3 C I believe that most of our cameras can be maintained to -3 C and I doubt that all our cameras in a position are to be attained – 83 C, so I think that this area should be good enough coverage. I chose to use a 100k pot at some point, because I’m going to the plate with a dual digital potentiometer DS1267 replace. I do not allow for a distance, using Win245 software controllable temperature control and the 100K pot is the control loop is working is to be updated very easily. I intend to use the pot on the remaining DS1267 to replace R43 on the board pre-amp. This allows a selectable gain control software for the camera cookbook. More later.

I would recommend the maximum TEC voltage regulator and leave it there. The circuit temperature controller does the rest. You may want to perform delete on the part of the adjustment of supply voltage and tie the totally positive TEC voltage directly at the outlet of the resistors R1 and R2 in parallel with power supply stocks cookbook. There is much room is available for experiment. Roy says that his power TEC does not need to precisely controlled tension, but also be filtered and have less than 10% ripple. So, I think you no harm by not following the proportion of the supply voltage regulation will do Peltier.

Thermostat controlled with SCR circuit

This first circuit is designed by me to replace the mechanical switches used in some thermal Electric
I have heaters.

The electrical contacts to these mechanical thermal switches are always stoned and “no longer be trusted.”
They could easily be welded together, the maintenance of these heating on full. It is definitely not good!

Coarse adjustment of the temperature is a trimmer on the track, set to give a nominal range
When using the fine adjustment.

It is quite difficult in a D-53, manufactured by NEC. The plumb line that is not isolated to the body of the thermistor is arranged. Why is it when you use the wire must be insulated to withstand the high temperatures such as fiberglass insulation against pipe.
What is the size of the thermistor is the disk diameter 7 mm and a thickness of 2 mm.
The end temperature control is a standard isolated potentiometer with a knob and / or good
Protection against electric shock. Harter can be adjusted with this controller
Auto-On and Off, “which automatically adjusts the room temperature.

The power control for the triac should be a 2 watt potentiometer with a knob isolated and / or
Tree for protection against electric shock.

It can also be set up a 2-watt resistor on the circuit, an appropriate level of heat.
“In general, full on,” how would the “Normal” setting when you use the contacts.

On the chart, show me a 10 Meg resistance hysteresis. This may be of Lower Austria or higher
depending on how many degrees of difference between you and off cycles.
Values between 100 K-ohms and 22 ohms, Meg are acceptable.

The disadvantage of a triac is not always 100% efficiency.

1000 Watt Space Heater Thermostat circuit

What follows is a circuit I recently built thermostat controlling a heater 1.3 KW. The heating element (not shown) is connected in series with two back to back SCR 16 Amp (not shown) that are controlled by a small pulse transformer. The pulse transformer has three identical windings, two of which are used to provide trigger pulses to the SCR, and the third winding is connected to a pair of PNP transistors which alternately supply pulses for the transformer, the beginning of each cycle AC half. The trigger pulses are applied to both SCR to the beginning of each AC half cycle but only one leads to the second of alternating polarity.
DC power for the circuit is shown in the bottom left of the drawing and use a 1.25uF, 400 volt non-polarized to about 50 mA of current from the AC line. The current is rectified by two diodes and used to load a couple of large low voltage capacitors (3300uF), which provide about 6 volts DC to the circuit. The voltage is regulated by zener 6.2 volts and 150 ohms in series with the line limits the current surge when the power is on.

The relatively low (output at pin 13) serves as a zero crossing detector and produces a square wave at 60 Hz in phase with the AC line. The phase is shifted slightly from 0.33 uF, 1K and 220K of the network so that the SCR trigger pulse comes when the line voltage a few volts above or below zero. The SCR will not trigger at exactly zero, because there is no voltage to maintain conduction.

The first two comparators operate in the same manner described in the “electronic thermostat and the relay” circuit. A low level on pin 2 is produced when the temperature is above the desired level and inhibits the square signal on pin 13 and prevents operation of the SCR. When the temperature drops below the desired level, pin 2 moves to a condition of open circuit, allowing the square wave on pin 13 to trigger the SCR.

The dial near the center of the design (pins 8,9,14) is used to allow the heating to be performed manually for several minutes and stops automatically. A momentary toggle switch (shown connected to a resistance of 51 ohms) is used to discharge the 1000uF capacitor to the pin 2 of the confrontation was in a state of open circuit, allowing the square wave of 60 Hz to activate ” SCR and the power of the stove. When the capacitor reaches about 4 times to return to normal operation of the circuit that controls the operation of the thermistor. The momentary switch can be enabled or disabled so that the capacitor charges more than 4 volts and off the heater if the temperature is above the adjustment plate.

This circuit is known as a thermal sensor. In principle, this circuit or NTC thermistor as a sensor. This diagram, where the temperature is almost simple sensor data subsequently amplified by Op-Amp 741, which is then compared with pl P2, etc. served as governor of sushi, then transistor Q1 to move Relay.

heat sensor circuit

Transistor Q1 is a 2N2222 (A) 2N3904, NTE123A, ECG123A, etc. Not all are critical. Only acted as a relay for each type of work, therefore, deconvolution, the length of the energy needed to activate the power coils. D1, 1N4148, acts as a spark arrester on the relay contacts open and abolishs to false trigger. Feel free to use another type of matter, such as 1N4001 or something. Solder directly on the ‘+’ and ‘-’ relay terminals.

Electronic Part List:

IC1 = LM741, LM741CN-ND, LM741CN, NE741, μA741, etc.
Q1 = 2N2222 2N2222 2N3904-ND
D1 = 1N4148
Th1 = 10K
Re1 = 12V relay
R1 = 47K
R2 = 150 – 390K (if ralay “chatters”)
R3 = 1K8,
R4, R5 = 2K2
P1 = 50K Trimmer Pot

Heat Sensor PCB Diagram

How to work
Th1, 50K thermistor is a standard type. I was looking for a bar or rectangular thing. Available from Tandy Radio Shack. Almost every kind will do. I experimented with different models from 22K to 100K, and everything worked fine after replacing the trimmer pot and a small “tuning.

Which was used in the above figure is the circuit model under 50K Fenwal (# 197-503LAG-A01). 50K was measured accurately at 25 ° C and 10% tolerance. Increasing resistance temperature drop. Tolerance for my purposes (cooling power coolrib wide) is 10%.

Heat Sensor Part On PCB Diagram

Another name for this thing is “NTC”. NTC means a negative temperature coefficient “, which means that when the temperature decreases the resistance of the thermistor increases. You might have to buy at the lowest price. Some are thermistor, at least $ 4.00, but for $ 55.00 Canadian dollars for the type of glass encapsulated (the best).
I replaced my 60k thermistor type of glass hermetically sealed, such as the environment, and so my question corrosive particles that may affect future performance include.

BOURNS trimmer P1 is a simple rule, and wide temperature range of this circuit. I used a 10-style in the mood for some fine tuning, but the nature of regular use.

R1 is the “safety” resistor P1 trimmer pot is completely adjusted to “0″ ohm. Just then, the thermistor will receive a full 12 volts, and so hot that it puts blisters on your fingers …
R3 feeds back a bit in the differential op-amp relay to rattle when thermistor temperature reaches remove. Depending on the application and the type used in the 1 Re1 quarter and starts around 330K and reduce its value to the desired result. 150k value reported in the system worked for me. Impairment of hysteresis R2 more resources, but use more than necessary. Or temporary use of the trimmer pot and read the value. 120K worked for me.

Transistor Q1 is a 2N2222 (A) 2N3904, NTE123A, ECG123A, etc. are not critical. Acts as a relay switch in almost every type of work, and could provide the current necessary to activate the relay coil.

D1, 1N4148, acts as a spark arrestor when the relay contacts to open and eliminates false start. For my purposes, 1N4148 is good for the relay I have a little amp. However, you can create a number of diodes used here, my next choice would be regular target 1N4001 or something to be used as a kind of relay connected to the control process more than 1 ampere.

Digagram circuit and PCB layout are current C1, C2, R7 and LED. C1 and C2 are new to the relay switching noise in some applications to remove. Optional LED and resistor was added to the circuit and layot for your convenience. Relays used in this kit is a type of small 12V/0.5A. If the relay clicked increase the feedback resistor R3 to 180km or something “higher, and a small ceramic cap coils connected in parallel with diode D1. Diode 1N4148 is designed for small relay. When using relays as 1N4001 or 1N4004.

If you want to create a custom PCB, try the following. PCB is equipped with holes for the relay, but not your specific relay. It was designed for one type of arene DC12V HB1. Diversity and the relay model is for adults only. How to join? Well, I had a lot of space on the board mount relay. You can also mountain, and connect various cables. Use of silicone adhesives, cyanoacrylate ester (crazy glue) or double-sided tape on his relay place. Works well. Note that the PAC and the imposition Page Not according to the timetable for drawing fans. PCB is about 1.5 x 3 inches (4.8 x 7.6 mm)
If you print inkjet PCBs probably not to scale. Try 8-pin IC socket for mounting on a printed copy to ensure that it matches the scale for printing on a sheet of transparency and PCB …

Engine water temperature sensor circuit

For user who love developping in electronic project ,we have some circuit for Car Boiler or water Temperature Sensor of this circuit can be to display Temperature of Car water Boiler with 7-Segment Main of circuit .

We have use IC CA3161 and CA3162 for control all,The Car Water Temperature Value can’t be keep always while no power supply as It hasn’t EEPROM to save.
This circiut will be display for you monitoring only that is make sense to implement in your car.

This circuit measures the car water temperature.
The IC CA3161 is a counter and 7segment LED driver to display amount of temperature on 7segments.
About a temperature sensor is a diode which number 1N4148.
This is like of the Car Radiator.
Connect to the 5 Vdc power supply from Car Battery that you can use a LM7805 for  +5Vdc regulation with low cost voltage regulator.

 For the method of temperature measurement: first after application of at least 2 currents of a thermal sensor, including at least two output signals are generated calculating an analog signal to the temperature of the reaction at least two signals, the analog signal representative of temperature to the temperature sensors, a calibration, the calibration factor is calculated by applying the order of leastthree thermal sensor, and calibration of a gap in the temperature of the concept of analog signal, that the development gap-term is at least a series of parasite resistance to the thermal temperature sensor and the signal processing theanalog digital signal to a temperature reference value for the conversion of the reference value for the transition is consistent with the calibration.