Protecting an outdoor metal gate

Support
, , , , , , ,
1

I’m using a Qolsys IQ panel 2, and have found myself in a bit of an arms race with people breaking into my house. The latest development is that someone sawed through the metal gate on my front door and actually bent the bars back far enough to be able to reach in and turn the deadbolt. Fortunately they didn’t get through my front door (which is alarmed), but this would allow them to steal my mail, and I’m concerned it could be a precursor to other undesirable activity. I’d like to be able to detect such sawing. Also, since it should take a while to saw through a metal gate, this would be a good opportunity for the police to nab whoever is doing this.

I’m intrigued by two things. The interlogix 5402 assault sensor claims to detect people sawing through metal. In addition, this video from SuretyDIY shows how to hook up a wired sensor to an RE101 wireless sensor inside a waterproof junction box, so as to monitor an outdoor gate. I’m wondering if it would be possible to combine these ideas, but it raises a number of questions.

First, does anyone have experience with the assault sensor, and how precise is it at detecting sawing? I don’t want this alarm to go off if someone walking by just kicks the gate, or if the mailman just stuffs a bunch of letters through the mail slot.

Second, the assault sensor is a battery-powered device, so presumably should be protected from the elements. Would it be feasible to mount the assault sensor inside a junction box, or would this change the vibration pattern to the point of invalidating it? Or should I consider the externally powered variant, the 5422, and put a battery for it inside the junction box?

Third, are there any all-in-one solutions or other approaches I should be considering? For example, are I’ve seen mixed reports on these forums of Schlage Z-wave locks working outdoors, so maybe I could install a smart deadbolt and (don’t know if this is possible) trigger an alarm if someone opens the deadbolt from the inside when in away mode.

Thanks for any advice.

2
First, does anyone have experience with the assault sensor, and how precise is it at detecting sawing? I don’t want this alarm to go off if someone walking by just kicks the gate, or if the mailman just stuffs a bunch of letters through the mail slot.

The Assault sensors you are referencing are designed to capture tampering via sawing/drilling etc. in solid sheet metal. They are not designed for the application you are referencing, so I couldn’t speak to the efficiency in this case and I would not recommend using them in that fashion. See below from the manual:

“Sheet metal enclosures to be protected shall not exceed 2 x 4 x 1 ft.
(61 x 122 x 30.5 cm), and shall have a maximum wall thickness of
0.135 inches (0.343 cm). The enclosure must be solid sheet
metal, have all sides connected (welded, bolted, etc.), and the lid
attached by hinges or screws”

For example, are I’ve seen mixed reports on these forums of Schlage Z-wave locks working outdoors, so maybe I could install a smart deadbolt and (don’t know if this is possible) trigger an alarm if someone opens the deadbolt from the inside when in away mode.

Regarding Z-wave locks, a couple considerations:

  1. You should never use a Z-wave lock in a location where the interior portion of the lock will be outdoors. Humidity and corrosion are likely to damage the lock over time.

  2. Z-wave locks do not act as alarm sensors and you cannot create rules to trigger alarms based on Z-wave activity. You could monitor it for lock activity and receive notifications but it could not trigger alarm activity.

Third, are there any all-in-one solutions or other approaches I should be considering?

This is an interesting issue, and if you are experiencing a lot of destructive efforts on the part of intruders, low tech solutions may be good to consider as they will be less expensive to implement or replace, and some exterior hardening can help.

In any case where someone may be able to reach through an opening to the rear of a deadbolt lock, such as a lock near glass or slotted gate, it would be best to use a deadbolt without a thumb-turn, one that has a key-way on both sides. This will keep individuals from being able to easily unlock the door if they get access to the back of the lock.

Additionally, in terms of attempting to sense the act of cutting through the gate, depending on the complexity of the gate you may be able to create an effective sensor out of just wire and a transmitter like the RE101.

Commonly to detect if someone is trying to cut through wiring/piping on outdoor air conditioning/heating units, a sensor made from a simple closed loop of wire is run along the cable or pipe that would be cut. When the wire is cut, the circuit opens and the RE101 would trip the alarm. This could be programmed as a 24 hour zone, so that whether the panel is armed or not, it would generate an immediate alarm if cut.

3
In any case where someone may be able to reach through an opening to the rear of a deadbolt lock, such as a lock near glass or slotted gate, it would be best to use a deadbolt without a thumb-turn, one that has a key-way on both sides. This will keep individuals from being able to easily unlock the door if they get access to the back of the lock.

Thanks. I thought of this. Unfortunately, when I asked my locksmith to do this, he refused because the gate is a potential means of egress. Moreover, he said that now that he knows what I want to do, he will refuse to sell me a double-cylinder deadbolt or re-key one for me. I looked into rekeying kits for doing it myself, but it looks like of expensive. I need master pins so that the interior key, if stolen, cannot get into my house, as I’ll have to hang an emergency exit key right by my front door. Doing it myself seems like it would require, in addition to the double-cylinder deadbolt itself, $100 for the rekeying kit with master pins, $500 for a key cutting machine like the PAK-A-PUNCH, plus some key blanks. Alternatively, maybe I could get a double-cylinder deadbolt with an IC core and take the cores to a locksmith, but those probably aren’t compatible with the other locks on my house (which has about 15 cylinders between all the doors, gates, and locks), so probably also becomes expensive if I want one key for the whole house.

Are there any Z-wave-controlled magnetic locks? I wonder if I could have a Z-wave controller in my house and run wires out to a magnetic lock on the gate, such that if anyone cuts the wires an alarm goes off. Also I could install a panic button to get out.

Additionally, in terms of attempting to sense the act of cutting through the gate, depending on the complexity of the gate you may be able to create an effective sensor out of just wire and a transmitter like the RE101.

Commonly to detect if someone is trying to cut through wiring/piping on outdoor air conditioning/heating units, a sensor made from a simple closed loop of wire is run along the cable or pipe that would be cut. When the wire is cut, the circuit opens and the RE101 would trip the alarm. This could be programmed as a 24 hour zone, so that whether the panel is armed or not, it would generate an immediate alarm if cut.

Now this is a very intriguing suggestion, but I’m not sure it would work with the RE101.
The RE101’s instructions themselves are unfortunately very vague on electrical configuration, just saying zone 2 triggers “when contact changes to alarm condition.” However, the video I linked in the original post suggests hooking the RE101 to a Sentrol 1085W, which according to the data sheet is a normally open sensor. From that I infer that the RE101 expects a normally open circuit to close when the gate is opened. Here what I’d have is a normally closed circuit that opens when someone cuts through the wire.

Am I misunderstanding how the RE101’s second zone should be wired? Or are there other wireless sensors that I should be considering?

Thanks for your help.

4
Thanks. I thought of this. Unfortunately, when I asked my locksmith to do this, he refused because the gate is a potential means of egress

An alternative to stopping access to the thumb turn would be to monitor it. Depending on the setup you may be able to use a recessed Plunger style sensor to monitor when the Bolt is retracted. The plunger sensor would be installed behind the bolt strike plate in the frame cavity where the bolt extends, so that when the bolt is extended it presses down on the plunger.

Wired plunger sensors could then be attached to an RE101. You can typically find wired plunger sensors for under $5

Are there any Z-wave-controlled magnetic locks? I wonder if I could have a Z-wave controller in my house and run wires out to a magnetic lock on the gate, such that if anyone cuts the wires an alarm goes off. Also I could install a panic button to get out.

Adding Z-wave control would basically just be adding something like a Mimolite relay as a control for a standard Magnetic access control lock. This is a rather heavy-duty and power-dependent solution though, so I wouldn’t really recommend it, but you could use the same concept with a closed loop of wire running parallel with the power wires if you want to monitor them for cuts.

Now this is a very intriguing suggestion, but I’m not sure it would work with the RE101. The RE101’s instructions themselves are unfortunately very vague on electrical configuration, just saying zone 2 triggers “when contact changes to alarm condition.” However, the video I linked in the original post suggests hooking the RE101 to a Sentrol 1085W, which according to the data sheet is a normally open sensor.

The data sheet is correct, but a bit misleading.

The sensor circuit on a 1085 is Normally Closed. The door contact has its reed switch pulled closed by the magnet when at rest, then when the door is opened, the sensor moves from the magnet and the circuit opens.

Refer to the “loop type” described in the data sheet, not the electrical config, to determine how it functions in a sensor circuit.

The RE101 functions with NC sensor circuits, not NO.

5

I see, so essentially “normal” in the 1085 spec means when the door is open, not when it is closed. Now I understand, thanks. This was very helpful.

Any recommendations on what type of wire would be adequate to stretch across a gate. Even better, is there any tamper-detection wire mesh product I could stretch across the gate?

6
Any recommendations on what type of wire would be adequate to stretch across a gate. Even better, is there any tamper-detection wire mesh product I could stretch across the gate?

I would likely just use 22/2 for the sensing circuit.

I am not aware of any out of the box solution for this type of application, no.