The system is designed to dial out on a phone line to a central station or a police monitoring system. These alarms have built in warnings for a failure in the phone line. This is a safeguard so you know the system is not working properly.
So long as the system is operational and cut off from the phone line, it will continue to beep. By removing parts of the keypad and circuit board, you have apparently shut down at least part of the system. If you truly don't want the system on, you need to remove power from the entire system.
The power to the system is probably controlled by master box (probably where the battery was) that has a wire running to a transformer on or near your main power panel. The simplest way to stop the system is to disconnect the wires going from the transformer to the alarm control panel.
The transformer wires are low voltage (usually 24 volts) on the outside (inside the panel they are 120 volts). To be safe, it is better to turn off the breaker connected to the transformer before disconnecting the wire. If you cant figure out which it is, have a flashlight handy, turn off the main breaker, then disconnect the wires. Then turn the main back on.
Once the system is disconnected form both the mains and the battery, it cannot send a false alarm or activate the safety beeper.
When an alarm trips, it can send out one or more of three types of alerts:
- local - an audible alarm rings at the property
- direct police connection - when the alarm rings, it goes off in the police station itself (rare)
- central station - an alarm goes to the alarm monitoring company, which then alerts the police in certain circumstances (such as no one answers or fails to give a password following a callback to the house).
Some alarm setups are local only, some remote (police or central station) only, and some are both.
Two things control whether the alarm will go out:
- is there power?
- is there a connection to the monitor (if any)
Almost all serious alarms have battery backup to ensure that, even if the power is cut, the basic alarm system is still functional. If there is no battery backup, cutting power lines will nullify the alarm.
Local: Assuming power, AC or battery, a local alarm will ring upon intrusion, regardless of whether cables are cut.
Remote: Connections to police or central stations are most often handled through conventional telephone lines. These may be landline connections or cable/internet connections (if phone service is via the cable system or other internet provider).
Even if power is cut, landline telephone service is often still active, since landlines have their own power feed. But if the telephone line is cut, the signal cannot go out.
Cable/internet phone, on the other hand, relies on modems that need AC power. If power is cut, cable phone does not work. If the cable line is cut, this would also prevent a signal going out.
Cellular remote: Some alarm systems offer a cellular connection. This is like having a dedicated cellphone built into the alarm system. These systems function even if the landline or cable line is cut. They will continue to function even if the AC power is cut (assuming a battery backup, which would be standard on a cellular type setup).
Whether your system would survive a wire attack depends on the type of system you have. Only a cellular based system with a battery backup can withstand all attacks on the wires that feed a property. But many systems will detect a disruption of power or telephone connection, make a call to the owner to see if there is a problem, and alert authorities of the monitor does not get satisfactory assurances. The level of security is a function of how much you are willing to pay and how concerned you are about various levels of risk, and the particular protocols of the alarm monitoring service.
Best Answer
Well, I ended up going into the attic and tracing the wires. Hot and sweaty work, but I believe I found the power lines. They ended up terminating to a powerbrick that was run through the ceiling of my garage, next to the garage door motor plug.