Velleman K2649 User guide

Total solder points: 166+116
Difficulty level:
beginner 1o 2o 3o 4þ 5oadvanced

Thermostat with LCD-display

Features:

þ Wide measuring and regulating range: -50 to +150°C (-60 to +300°).
þ Adjustable hysteresis: 0,2°C (0,4°F) to 10°C (18°F).
þ Resolution of the display: 0,1°C or 1°F.
þ Can be set for degrees Celsius or Fahrenheit.
þ Connecting capability for economy switch.

K2649

Specifications :

• Power supply and transformer included.

• Mains voltage: 220/240V (110 for USA and Canada).

• Relay output: 240V, 3A max.

• Dimensions: 123.5x62x65 mm.

ILLUSTRATED ASSEMBLY MANUAL H2649IP-1

2

VELLEMAN Components NV

Legen Heirweg 33

9890 Gavere

Belgium Europe

www.velleman.be

www.velleman-kit.com

0.000

Assembly hints

1. Assembly (Skipping this can lead to troubles ! )

Ok, so we have your attention. These hints will help you to make this project success­ful. Read them carefully.

1.1 Make sure you have the right tools:

• A good quality soldering iron (25­40W) with a small tip.

• Wipe it often on a wet sponge or cloth, to keep it clean; then apply solder to the
tip, to give it a wet look. This is called ‘thinning’ and will protect the tip, and en­ables you to make good connections. When solder rolls off the tip,
it needs cleaning.

• Thin raisin-core solder. Do not use

any flux or grease.

• A diagonal cutter to trim excess wires. To avoid injury

when cutting excess leads, hold the lead so they
cannot fly towards the eyes.

• Needle nose pliers, for bending leads, or to hold components in
place.

• Small blade and Phillips screwdrivers. A basic range is fine.

For some projects, a basic multi-meter is required, or

might be handy

1.2 Assembly Hints :

⇒ Make sure the skill level matches your experience, to avoid disappointments.
⇒ Follow the instructions carefully. Read and understand the entire step before you

perform each operation.

⇒ Perform the assembly in the correct order as stated in this manual
⇒ Position all parts on the PCB (Printed Circuit Board) as shown on the drawings.
⇒ Values on the circuit diagram are subject to changes.
⇒ Values in this assembly guide are correct*
⇒ Use the check-boxes to mark your progress.
⇒ Please read the included information on safety and customer service

* Typographical inaccuracies excluded. Always look for possible last minute manual
updates, indicated as ‘NOTE’ on a separate leaflet.

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Assembly hints

1.3 Soldering Hints :

Mount the component against the PCB surface and carefully solder the
leads

Make sure the solder joints are cone-shaped and shiny

Trim excess leads as close as possible to the solder joint

AXIAL COMPONENTS ARE TAPED IN THE CORRECT

MOUNTING SEQUENCE !

REMOVE THEM FROM THE TAPE
ONE AT A TIME !

4

5%

4K7= ( 4 - 7 - 2 - B )

1%

4K7= ( 4 - 7 - 0 - 1 - 1 )

COLOR= 2… 5

C O D

E

KODE

COLOR= 2...5

KLEUR

CODIFI-

CATION

DES COU-

CODE

COLOUR

FARB

KODE

KODE

FARGE-

KODE

FARVE-

FÄRG

SCHEMA

VÄRI

KOODI

ORES

CODIGO

DE COL-

LEURS

I P E SF S DK N D GB F NL

CODIGO

DE CORES

CODICE

COLORE

C O D E

0 Nero Preto Negro Musta Svart Sort Sort Schwarz Black Noir Zwart 0

1 Marrone Castanho Marrón Ruskea Brun Brun Brun Braun Brown Brun Bruin 1

2 Rosso Encarnado Rojo Punainen Röd Rød Rød Rot Red Rouge Rood 2

3 Aranciato Laranja Naranjado Oranssi Orange Orange Orange Orange Orange Orange Oranje 3

4 Giallo Amarelo Amarillo Keltainen Gul Gul Gul Gelb Yellow Jaune Geel 4

5 Verde Verde Verde Vihreä Grön Grøn Grønn Grün Green Vert Groen 5

6 Blu Azul Azul Sininen Blå Blå Blå Blau Blue Bleu Blauw 6

7 Viola Violeta Morado Purppura Lila Violet Violet Violet Purple Violet Paars 7

8 Grigio Cinzento Gris Harmaa Grå Grå Grå Grau Grey Gris Grijs 8

9 Bianco Branco Blanco Valkoinen Vit Hvid Hvidt Weiss White Blanc Wit 9

A Argento Prateado Plata Hopea Silver Sølv Sølv Silber Silver Argent Zilver A

B Oro Dourado Oro Kulta Guld Guld Guldl Gold Gold Or Goud B

Construction

R...

R...

The very precise digital display of both the set and actual
temperature makes this thermostat very easy to use.
Also very useful is the connecting capability for an
'economy switch': when the contact is closed then the set
temperature is decreased by a number of degrees.
No measuring apparatus is needed for adjustments.
Thanks to the wide setting range of both the hysteresis
and the desired temperature, this kit can also be used for
a lot more applications than only regulating room tempera­ture.

Assembling instructions :

The whole consist out of two parts : the regulating and
power supply module P2649V and the display module
P2649D

A. Power supply mode

1. Resistors

q R1 : 560 (5-6-1-B)
q R3 : 100K (1-0-4-B)
q R4 : 100K (1-0-4-B)
q R6 : 100K (1-0-4-B)
q R15 : 220K (2-2-4-B)
q R16 : 220K (2-2-4-B)
q R17 : 560K (5-6-4-B)
q R18 : 560K (5-6-4-B)
q R26 : 820 (8-2-1-B)
q R27 : 1K (1-0-2-B)

q R28 : 10K (1-0-3-B)
q R29 : 82 (8-2-1-B)
q R34 : 6K8 (6-8-2-B)
q R35 : 5M6 (5-6-5-B)

2. Metalfilm resistors

q R20 : 10K (1-0-0-2)
q R21 : 10K (1-0-0-2)
q R22 : 47K (4-7-0-2)
q R23 : 47K (4-7-0-2)

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Construction

C...

3. Diodes
Watch the polarity !

CATHODE

D...

q D1: 1N4007
q D2: 1N4007
q D3: 1N4007
q D4: 1N4007
q D5: 1N4148

4. Zenerdiode
Watch the polarity !

CATHODE

ZD...

q ZD1: 8V2

5. IC socket, watch the
position of the notch!

q IC2 : 14p

6. Potentiometers

R4

q RV4 : 10K

7. Transistor

q T1: BC557B

8. Ceramic Capacitor

q C3: 100nF (104)

9. Potentiometers

RV...

q RV5 : 4M7

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Construction

C...

10. Capacitor

q C10 : 1µF/63V

11. Terminal blocks

connectors

q J1 : Mains.

q J4 : “ES” Economy

switch.

q J2 :

— For heaters use the

contacts : ‘C’ & ‘NO’.

— For coolers use the

contacts : ‘C’ & ‘NC’.

G The connection side of

the connectors must point
to the PCB-opening!

12. Fuseholder & Fuse

F...

q F1 : 100mA (slow)

13. Electrolytic

Capacitors.
Watch the polarity !

q C2 : 100µF
q C1 : 1000µF

14. Relay

q RY1 : VR15M121C

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Construction

15. Transformer

220V 12V

17. Flatcable

TRANSFORMER

q TRAFO1 : 12V - 0,1A

q J3 : FC8 “9 wire”

16. Flat cable. watch
the position of the
notch!

q IC2 : LM324

18. Choosing hysteresis

— Small hysteresis

If you desire a small hysteresis (adjustable from 0,2 to 1°
C or from 0,4 to 4°F), then fit for R24 and R25 a 180K
metal film resistor (brown, grey, black, orange).

— Larger hysteresis

If you prefer a larger hysteresis (between 1 and 10°C or
2 and 20°F, for instance for water heaters and such-like),
then fit a wire link for R24 an R25.

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