arming-disarming home alarm systemThis is probably too obvious. An alarm system only works as an alarm system when it is armed, but there are variations to a system being armed and disarmed that can make a difference in what happens when it is triggered.
Systems don’t always need to be armed to detect an event and send out a notification (see below for more information on this).
As noted in the opening paragraph there are 2 main states for a system – armed or disarmed.


When the system is armed it is active and set to detect an intrusion, to sound the alarm and get a notification out. When armed there are a different modes that a system be set in.

Stay – this is the mode you choose when you want to arm the system but someone is staying at home. The door/windows contacts will be activated and the alarm will be sounded when triggered and/or notifications sent out. The motion sensors that detect movement in the house are not activated. In this way you can move around your home without sounding the alarm. If you have pets and the motion sensors are not pet-friendly you may need to set the system in this mode when everyone is away otherwise you may have problems with false alarms as your pets move around your home.

Away – this is the mode is used when no one is staying at home. All sensors are activated and when they are triggered the alarm is sounded and/or notifications sent out. However, you can choose that sensors in a particular zone (see more below) not to sound an alarm and to just notify you that there has been an intrusion or incident.

Delay – there are two alarm delays that can be programmed into an armed mode. One for when you are leaving and one for when you come home. When you open the door the alarm delay gives you a chance to disarm the system using the keypad to enter your pass code and press the disarm button. In the same way when you arm the system using the control panel you need time to leave the house before the system is activated otherwise you trigger the alarm resulting in a false alarm.

Instant – the alarm is activated instantly it is armed or the alarm is sounded instantly a sensor is triggered. Today, there is less need to have an alarm delay programmed into your system.  There are now a number of ways to set or disarm the alarm using remote key fobs and smartphones. This means you don’t have to be inside the house to arm/disarm so there is no need for a delay. You may also want the window/doors to be armed instantly in stay mode if no one is leaving the house even when using the keypad.

Disarmed mode – this is when the system is not active. When the security sensors detect movement the system does not respond by sounding the alarm. A system like Simplisafe can send you a notification to let you know a door has been opened or movement been sensed. A log will be kept that you can access to see the comings and goings.


Zones play an important part in how the system responds when sensors are tripped. A zone is a number or name assigned by the system to one sensor or a group of sensors. See more here. This is how systems give you the option of arming in stay mode. The motion sensors are assigned to a zone(s) that are set up not to be active when the system is armed this way.

Environmental sensors are assigned to a zone that is always on no matter what status or mode the system is in – armed or disarmed. This is because you need to be warned if there is an issue. They detect when there is a problem with temperature, smoke, carbon monoxide or water.

Internet systems like iSmartAlarm give you much more options with how your system responds to individual sensors being triggered independent of the mode. You can have the lights come on when a motion sensor detects movement when system is in stay mode.

A no frills DIY alarm system like the Fortress S02-B gives you a limited number of options in the actions that can happen when you arm the system. It gives you the option of stay and away modes and the choice to change the alarm delay and response (armed or not) for the different zones. It does do these basics well.

If you are looking for more choice you can either go for a system with a monthly monitoring fee like Simplisafe or an internet based system that works through your internet connection like SmartThings or iSmartAlarm. These systems give you much more flexibility but the overall cost is more. You can customize them to your own particular wants and lifestyle.

Alarm modes are an important part of a home security system and you have quite a bit of flexibility with DIY systems to set the system to respond when sensors are triggered in each of the different modes. This gives you the chance to customize to cater for your own person circumstances.

Filed under: Buying Advice

Like this post? Subscribe to my RSS feed and get loads more!