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Security lights controlled by alarm system

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J de Beer

New Member
Good day
I am a pensioner in South Africa with a little knowledge of electronics. I please need some help with the following: I have built a circuit that controls my security lights via the security system is and it is 100% functional for a long time.
I have only one problem and I hope someone can assist me. When the power is turned on, the "Kingdom Electronics 12v Versatile Timer" reseives a "jolt/surge?" Of power and the relay closes for a second and then opens to the normal position. I have removed the trigger wire and tested it with the same result. What can be done to prevent the relay of the timer to unnecessary activate for a split second? The system works 100% in all other respects.

Thanx in advance for any help.
 

dr pepper

Well-Known Member
Most Helpful Member
Hi and welcome.
Sounds like the circuit uses a 555, to be honest I think you'd be better looking for another timer that doesnt have the same parasitic.
 

alec_t

Well-Known Member
Most Helpful Member
Can you post a schematic of the timer?
 

KeepItSimpleStupid

Well-Known Member
Most Helpful Member
The timer might be here: http://www.kesa.co.za/timer.htm

There are three things you can do:

1. re-seat the jumpers
2. Your power supply filter caps might be bad (too much ripple). You can try a 9V battery.
3. What is the chip # of the IC. If the reset circuit is a simple RC network it could be bad.
 

AnalogKid

Well-Known Member
Most Helpful Member
The timer module uses a PIC 12F629 as the timing engine. As such, a brief relay pulse is a surprise and a sign of bad design.

Please post a drawing showing how the timer is connected to your system. Show every wire going to any connector position.

ak
upload_2018-2-15_14-6-24.gif
 

J de Beer

New Member
Good day
Thank you very much to everybody who tried to help. The timer is exactly the one that is shown. I will check everything and try to produce a drawing which I will post as soon as possible.
Kind regards
 
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