Showing posts with label 5. Show all posts
Showing posts with label 5. Show all posts

Saturday, September 20, 2014

Simple 5 Zone alarm Wiring diagram Schematic

This is a complete alarm system with 5 independent zone ssuitable for a small office or home environment. It uses just 3CM IC`s and features a timed entry / exit zone, 4 immediate zones and a panic button. There are indicators for each zone a“system armed” indicator. The schematic is as follows:

5 Zone alarm Circuit Diagram

5



Circuit Notes:
Each zone uses a normally closed contact. These can be micro switches or standard alarm contacts (usually reed switches).Suitable switches can be bought from alarm shops and concealed indoor frames, or window ledges.Zone 1 is a timed zone which must be used as the entry andexit point of the building. Zones 2 – 5 are immediate zones,which will trigger the alarm with no delay. Some RF immunity isprovided for long wiring runs by the input capacitors, C1-C5. C7and R14 also form a transient suppresser. The key switch acts asthe Set/Unset and Reset switch. For good security thisshould be the metal type with a key.

Operation:
At switch on, C6 will charge via R11, this acts as the exitdelay and is set to around 30 seconds. This can be altered byvarying either C6 or R11. Once the timing period has elapsed,LED6 will light, meaning the system is armed. LED6 may be mountedexternally (at the bell box for example) and providesvisual indication that the system has set. Once set any contactthat opens will trigger the alarm, including Zone 1. To preventtriggering the alarm on entry to the building, the concealedre-entry switch must be operated. This will discharge C6 andstart the entry timer. The re-entry switch could be a concealedreed switch, located anywhere in a door frame, but invisibleto the eye. The panic switch, when pressed, will trigger thealarm when set. Relay contacts RLA1 provide the latch, RLA2operate the siren or buzzer.

Saturday, September 13, 2014

5 to 30 Minute Timer


Simple to build, simple to make, nothing too complicated here. However you must use the CMOS type 555 timer designated the 7555, a normal 555 timer will not work here due to the resistor values. Also a low leakage type capacitor must be used for C1, and I would strongly suggest a Tantalum Bead type. Switch 3 adds an extra resistor in series to the timing chain with each rotation, the timing period us defined as :-

Timing = 1.1 C1 x R1








Note that R1 has a value of 8.2M with S3 at position "a" and 49.2M at position "f". This equates to just short of 300 seconds for each position of S3. C1 and R1 through R6 may be changed for different timing periods. The output current from Pin 3 of the timer, is amplified by Q1 and used to drive a relay.

Parts
Relay 9 volt coil with c/o contact (1)
S1 On/Off (1)
S2 Start (1)
S3 Range (1)
IC1 7555 (1)
B1 9V (1)
C1 33uF CAP (1)
Q1 BC109C NPN (1)
D1 1N4004 DIODE (1)
C2 100n CAP (1)
R6,R5,R4,R3,R2,R1 8.2M RESISTOR (6)
R8 100k RESISTOR (1)
R7 4.7k RESISTOR (1)

Tuesday, September 2, 2014

5 Volt Switching Regulator Power Supply

The switching regulator power supply used LM2575-5.0 on this schematic.
Read more

Tuesday, August 26, 2014

5 to 500 feet transmitter circuit diagram


This is so useful schema because this schema can transmit signals 5 feet to 500 feet.Here I have used common transistor 2N5225 If you are unable to find this you can use any general purpose transistor.




Note

# About L1 is mentioned on the picture

# This schema operates with 9V DC

# use 5cm wire as an antenna

Friday, August 22, 2014

5 Zone Alarm System

This is a complete alarm system with 5 independent zones suitable for a small office or home environment. It uses just 3 CMOS ICs and features a timed entry / exit zone, 4 immediate zones and a panic button. There are indicators for each zone a "system armed" indicator. The schematic is as follows:

5 Zone Alarm System Circuit Diagram


5


Circuit Notes
Each zone uses a normally closed contact. These can be micro switches or standard alarm contacts (usually reed switches). Suitable switches can be bought from alarm shops and concealed in door frames, or window ledges.

Zone 1 is a timed zone which must be used as the entry and exit point of the building. Zones 2 - 5 are immediate zones, which will trigger the alarm with no delay. Some RF immunity is provided for long wiring runs by the input capacitors, C1-C5. C7 and R14 also form a transient suppressor. The key switch acts as the Set/Unset and Reset switch. For good security this should be the metal type with a key.

Operation
At switch on, C6 will charge via R11, this acts as the exit delay and is set to around 30 seconds. This can be altered by varying either C6 or R11. Once the timing period has elapsed, LED6 will light, meaning the system is armed. LED6 may be mounted externally (at the bell box for example) and provides visual indication that the system has set. Once set any contact that opens will trigger the alarm, including Zone 1. To prevent triggering the alarm on entry to the building, the concealed re-entry switch must be operated. This will discharge C6 and start the entry timer. The re-entry switch could be a concealed reed switch, located anywhere in a door frame, but invisible to the eye. The panic switch, when pressed, will trigger the alarm when set. Relay contacts RLA1 provide the latch, RLA2 operate the siren or buzzer.


Author : Andy Collinson