AVT3085 Four Channel Digital Thermometer Instructions
- June 9, 2024
- AVT
Table of Contents
Four Channel Digital Thermometer
AVT 3085
ASSEMBLY DIFFICULTY
AVT3085 Four Channel Digital Thermometer
The circuit can be used wherever you need to continuously monitor the temperature in several points at the same time, over a wide temperature range. It can detect the absence or failure of a sensor.
Characteristics
- 4 measurement channels
- temperature measuring range: -55°C to +125°C
- accuracy of measurement: ±0.5°C (from -10°C to +85°C), ±2°C (from -55°C to +125°C)
- reading resolution: 0.1°C over full range
- no calibration required
- reading box: 2×16 LCD display
- power supply: 7…16 VDC / 200 mA
Circuit description
The circuit can be used wherever you need to continuously monitor the
temperature in several points at the same time, over a wide temperature range.
Due to the DS18B20 digital sensor with a resolution of up to 12 bits, the
system can measure temperature from -55 to 125°C with a resolution of 0.1°C.
The device reads temperature from the sensors in a single cycle, which
significantly increases the measurement rate. The device can detect absence or
failure of the sensor, as indicated on the display. Figure 1 shows a schematic
diagram of the circuit. IC U1 is an ATmega8 microcontroller clocked by an
internal RC oscillator at 1 MHz. Resistor R1 of 10 kΩ pulls up the Reset pin
to Vcc for the microcontroller was not reset by any interference during
operation. Input voltage is fed to voltage stabiliser U2 type 7805. Capacitors
C1, C2 and C3 filter the voltage for the microcontroller. The LCD display is
connected to the microcontroller in 4-bit mode. Potentiometer PR1 adjusts the
contrast of the display. The R/W signal is permanently connected to earth as
it is not used. To measure temperature it uses DS18B20 digital sensors with
high resolution and accuracy of measurement.
Fig. 1 Schematic diagram of
the thermometer
Mounting and start-up
Figure 2 shows a mounting diagram, and the photo shows a view of the assembled
board. Solder the components in order from the smallest to the largest. During
mounting, it is important to remember to solder all jumpers at the sensor
sockets. Capacitor C1 needs to be soldered “lying down”, as it is quite high
and must fit between the display and the board. Under the microcontroller use
the DIP28 socket. The device will not require any calibration or adjustment,
after energizing it is ready for operation. It must be supplied with a DC
voltage in the range 7…15 V. Dashes are displayed for any not connected or
defective sensors. Measurements from subsequent sensors are displayed from top
to bottom from left to right.
Fig. 2 Mounting diagram of the
thermometer
Example of sensor protection
List of components
Resistors:
R1:…………………………………………………………10 kΩ
R2-R5:………………………………………………….4.7 kΩ
R6: …………………………………………………………..56 Ω
PR1: ……..mounting potentiometer 5-10 kΩ
Capacitors:
C1:. …………………………………………..100 uF / 16 V
C2, C3:…………………………………………………100 nF
Semiconductors:
U1: …………………………………………………..Atmega8
U2: ………………………………………………………….7805
W1:……………………………………display LCD 2×16
Other:
Z: …………………………………………JUMPER – 4 pcs
Z1-Z4: ……………………………angle goldpin 3pin
CON1: ……………screw connection ARK2/500 Sensors DS18B20 4pcs
AVT
SPV reserves the right to make changes without prior notice.Installation and
connection of the appliance not in accordance with the instructions,
unauthorised modification of components and any structural alterations may
cause damage to the appliance and endanger persons using it. In such a case,
the manufacturer and its authorised representatives shall not be liable for
any damage arising directly or indirectly from the use or malfunction of the
product.
The self-assembly kits are intended for educational and demonstration purposes
only. They are not intended for use in commercial applications. If they are
used in such applications, the purchaser assumes all responsibility for
ensuring compliance with all regulations
This symbol means do not dispose of your product with your other household
waste. Instead, you should protect human health and the environment by handing
over your waste equipment to a designated collection point for the recycling
of waste electrical and electronic equipment.
https://serwis.avt.pl/manuals/AVT3085_EN.pdf
AVT SPV Sp. z o.o.
Leszczynowa 11 Street,
03-197 Warsaw, Poland
https://sklep.avt.pl/
References
Read User Manual Online (PDF format)
Read User Manual Online (PDF format) >>