Power Simon XT Alarm With Battery

Power Simon XT Alarm With Battery
Power Simon XT Alarm With Battery

The organization I work for has built over 75 new homes in some of the most economically impoverished neighborhoods in Chicago.  Security is a big issue.  After becoming aware of the losses we were sustaining I developed a battery-powered solution for wirelessly securing vacant homes that do not yet have AC power.

How to Power Simon XT Alarm With Battery

Voltage Regulator In Simon XT Alarm
My Voltage Regulator Installed In a Simon XT Alarm

Hardware Required:

Tools Required

  • Phillips Screwdriver (to disconnect the ac power wires from the panel)

Step 1:  Open up the Simon XT Alarm Panel

There are two oval buttons that must be depressed to release the catches on the top of the door of the alarm panel:

Simon XT Alarm Case Opening Buttons
Press the two buttons to open up the alarm panel

Step 2: Remove the internal battery if it is installed.

You are going to swap out the battery for my custom-made voltage regulator system that has been designed to be the same size and has the same connectors as the battery it replaces.  Spread the two white tabs that hold the battery inside the panel and lift the battery up and out of the alarm.

How to Remove Battery From Simon XT
Spread the two white tabs and lift the battery straight up and out

Once the battery is out you can disconnect the positive and negative wires from the battery’s terminals.

Disconnecting Simon XT Battery Terminals
Pull the battery connectors towards the middle to disconnect them

Step 3: Disconnect the AC power cord from the alarm panel

If you plug the alarm into AC power while my voltage regulator is installed, the alarm panel will attempt to “charge” the regulator like it is the battery and this could damage the regulator.  It’s best to disconnect the AC power cord when you are operating it in battery-powered mode.  Loosen the two Phillips head screws that hold the AC power wires:

Disconnect the Simon XT AC Power Cord From the Panel
Loosen these two screws to disconnect the AC power cord

Step 4: A word of caution about wiring polarity.

There is a built-in fuse in the battery wiring.  If you connect the battery or the voltage regulator it will blow the fuse.  The fuse is not user-replaceable so you’ll need to buy a new wiring harness.  Be careful when connecting the wiring.  Red wires stand for positive, or +, and Black wires signify negative, or -.

Simon XT In-Line Battery Fuse
In-line Battery Fuse

Step 5: Connect the voltage regulator to the alarm wiring.

Connect the red alarm battery wire to the + on the voltage regulator and the black alarm battery wire to the – on the voltage regulator as seen below:

Simon XT Voltage Regulator Connected
Connect the Voltage Regulator like this

Step 6: Snap the voltage regulator into the alarm panel.

The voltage regulator is designed to fit into the alarm just like the battery it replaces.  Make sure the battery wires don’t make an X where they cross each other or it will make the wires too thick and it will bend the case.  Also make sure the voltage regulator is below the lips on the two plastic arms that held the battery in place.

Simon XT Voltage Regulator Battery Wire Path
The voltage regulator wires run out the slot
Simon XT Voltage Regulator Wiring
Make sure the battery wires don’t make an x, adding additional thickness
Simon XT Voltage Regulator Installed Side View
The regulator should fit down in and be below the plastic fingers that held the battery in place
Simon XT Radio Antenna Wire Path
Make sure the antenna wire is snapped in place

Step 7: Run the battery wires out the holes in the alarm panel

Now I must admit that my battery spade connectors are a bit big and they are a tight fit to feed out the holes in the alarm panel case.  They will fit out though, one at a time:

Simon XT Regulator Wires Running Out Case
Run the voltage regulator wires out the hole in the back of the case

Step 8: Close up the alarm panel.

It should snap tight.  If it does not, you may not have the voltage regulator snapped into the battery slot correctly.  Often, if the alarm doesn’t want to shut it is because some of the wires are getting in the way when you are closing it–gently pull the wires leading out of the bottom of the alarm panel to pull out any extra wiring that may be getting in the way inside.

Step 9: Connect the voltage regulator to a 12-volt battery.

I buy the biggest 12-volt marine battery I can buy so it will last as long as possible.  Connect the red connector to the positive (+) of the battery and the black connector to the negative (-) of the battery as seen below:

Simon XT Alarm Connected to 12 Volt Battery
Connect the Red to (+) and Black to (-)

Step 10: Run a Communication Test

If you have a wireless modem inside your Simon XT then the first thing you should do after powering it up is to run a communications test to establish communications between the alarm provider and the alarm panel.  To run a communications test follow these steps:

Step A: Press the down arrow button until the screen reads “System Tests” and then press the OK button.

Simon XT System Tests Menu Item
System Tests Menu Item

Step B: Enter the programmers code and then push the OK button.

You’ll need to have been given this by whoever you purchased your alarm from.

Simon XT Enter Code Menu
Simon XT Enter Code Menu
Simon XT Code Entered
Code Entered

Step C: Press the down arrow until the screen reads “Comm Test” and press the OK button.

Simon XT Comm Test Menu Item
Comm Test Menu Item

Step D: Wait for the test to run.

This is what you will see while it is running:

Simon XT Comm Test In Progress
Comm Test In Progress

It should say “CDMA Test signal sent OK” or “GSM Test signal sent OK” if it is successful.  Press Status now” if it runs successfully.  If it doesn’t run successfully your antenna may be disconnected or you may be located where there is weak signal.

Simon XT Comm Test-CDMA test signal sent OK
CDMA test signal sent OK

Step 11: You can check the signal strength by pressing and holding the 5 button from the main screen:

Simon XT Hold 5 To Check Radio Signal Strength
Hold the 5 Down To Check Radio Signal Strength

I cannot remember the range of numbers it can give you but you can see the “bars” and there are 5 possible and in the case above, I only have 1 bar of strength.  I believe the number range is 0-20.

Step 12: Check the voltage being provided to the alarm by the voltage regulator.

The Simon XT alarm panel has a digital multimeter built into it and you can check the voltage of the internal battery OR in our case, the output of the voltage regulator.  When the Simon XT is at the main screen press and hold the 6 button as seen below:

Checking Voltage on Simon XT Hold 6 Button
Press and hold the 6 to check the voltage–6.6 Volts, perfect

Here’s what our application looks like with the Simon XT alarm panel mounted on a small custom-made base that allows for easy portability:

Battery Powered Simon XT Alarm System Deployment
Battery Powered Simon XT Alarm System Deployment
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