Premises Security (part 12) Summary

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Premises Security (part 12) Summary

So the sensors are chosen, the cameras are installed. The recording system has been chosen. Power has been assured for an acceptable length of time.
Let's do a final summary:

Part 1 discussed the different types of security systems.

Part 2 explained the differences between Local and Monitored alarms and Perimeter vs. State-change detection along with a look at some different video security surveillance cameras.

Part 3 looked at wireless vs. wired security systems.

Part 4 looked at setting up a video security installation.
Part 5 covered remote monitoring of the video installation and security risks associated with that. It also considered using Motion Detection.
Part 6 Began an overview of NON-video surveillance devices.
It covered;
The “closed loop”, Micro/Magnetic Reed/Thermatic & Pressure Mat switches
Part 7 Continued the overview of NON-video surveillance devices.
It covered detection of environment change rather than physical switch operation
It considered;
Pulsed Infra-red beams, Passive Infra-red (PIR) movement detectors, Proximity detection
Part 8 Completed the overview of NON-video surveillance devices.
We considered that security is more than just Intruder Detection so then looked at Temperature and Light/Darkness security sensors such as;
Thermal Fuses, Thermistor or semiconductor temperature monitors, LDR or Semiconductor light sensors.
Part 9 Considered the two points raised in Part #1 of this series.

The first point was the trade-off of cost & size vs functionality, risk and aesthetics. That led into the discussion in Parts #2 thru #8, of the various types of security system and the devices used.

The second point was the possibility of having the "best of both" in a small easily installed surveillance system AND
extended power coverage by use of a "UPS" as a power backup.
Parts #10 & #11 talked about battery life, working out run-time calculations and the different types of UPS. It also touched on power quality and preferred brands of UPS.

So that wraps up a very high-level view of premises security using digital video surveillance.
I will gladly discuss any specific questions which this series of articles may have either left untouched or perhaps stimulated.

In my next post, I'll start to look at some of the forgotten aspects of security of computer data, caused by corruption, theft or malicious intrusion by virus or hacking.

Premises Security (part 9) Non-video surveillance

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In summary to-date
Part 1 discussed the different types of security systems.
Part 2 explained the differences between Local and Monitored alarms and Perimeter vs. State-change detection along with a look at some different video security surveillance cameras.
Part 3 looked at wireless vs. wired security systems.
Part 4 looked at setting up a video security installation
Part 5 covered remote monitoring of the video installation and security risks associated with that. It also considered using Motion Detection.
Part 6 Began an overview of NON-video surveillance devices.
It covered;
The “closed loop”, Micro/Magnetic-Reed/Thermatic & Pressure Mat switches
Part 7 Continued the overview of NON-video surveillance devices.
It covered detection of environment change rather than physical switch operation
It considered;
Pulsed Infra-red beams, Passive Infra-red (PIR) movement detectors, Proximity detection
Part 8 Completed the overview of NON-video surveillance devices.
We considered that security is more than just Intruder Detection so then looked at Temperature and Light/Darkness security sensors such as;
Thermal Fuses, Thermistor or semiconductor temperature monitors, LDR or Semiconductor light sensors.
And so to Part #9 of the series where we return to finish considering the two points raised in Part #1 of this series.

The first point was the trade-off of cost & size vs functionality, risk and aesthetics which led into the discussion of the various types of security system and the devices used (Parts #2 thru #8)
The second point was the possibility of having the "best of both" in a small easily installed surveillance system AND extended power coverage by use of a "UPS" for power assurance.

Let's now look at this second point.
The Trade-off

As I stated in Part #1, there is often a trade-off by the manufacturers of Digital Security systems, between size, cost and reliability. To keep size and cost down, battery capacity is minimised. Which is fine for 80-90% of the time.
We often have short-term power outtages of less than 2 hours and the supplied internal backup batteries work just fine.

Impact on Wireless Installations

In a wireless based security installation it is much less of a problem since the sensors all have their own battery power and are designed to operate 24x7 for many months on a new set of batteries.

Impact on Wired Installations

In a wired installation the sensors often source their power from the security control panel. If that is not the case then they derive their power directly from the mains supply.
In either of these scenarios, an extended loss of power supply can potentially render the system either totally inoperative or partially compromised.

Wireless or Central-Power Solution

If the system is wireless or all detectors source their power from the central panel, overcoming this weakness is relatively straightforward.
There are at-least two ways in which this can be addressed. Unfortunately both are quite bulky solutions sinc they both require the use of additional batteries.

1. Using Battery Extender Packs

If the system supports, or can be easily adapted to support, an external battery pack, then this is by far the cheapest, easiest and most efficient solution.
Essentially all that is required is some form of well-ventilated and secure housing for the desired quantity and capacity of batteries.

Technical Considerations

Technically you will need to consider the distance from the additional batteries to the security panel because of voltage loss over longer runs of wire. You will also need to stay within the manufacturer's specification for their battery charging circuitry.

Physical Considerations

The housing should be of sturdy construction capable of inhibiting fire and containing any possible battery explosion or leakage of battery acid.
Because batteries under charge give off explosive gases, the housing also needs to be well ventilated.

2. Using UPS Power Security

If your security system does NOT allow for attachment of additional battery capacity, an alternative may be to run the system off a UPS.

A UPS or Uninterruptible Power Supply generates utility-grade power (in many cases of superior quality) in the event of loss of supply to the premises.

UPS Ratings

UPS' come in all shapes and sizes and are rated in VA or Volt Amp units.
This measure is roughly equivalent to Watts which is the rating more commonly found on household appliances.

For the more technical readers, the VA rating takes into consideration Power Factor efficiency so the VA rating will always be higher than the Wattage rating (eg. a 1500VA UPS will deliver about 1200W)

Units start as small as 150VA but these are primarily designed to provide only a couple of minutes run-time on battery, sufficient only to automatically shutdown a small computer.

Calculating Your UPS Capacity

To calculate the UPS capacity required to support a system, an approximation can be made by taking the current draw of the system (either rated value or measured draw) then deciding how long you want the system to operate.

In the next installment, I'll work through an example calculation as we consider required run-time, battery life, and the different types of UPS.

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Premises security (part 3) Wired or Wireless ?

Last installment we looked at a couple of different cameras which can be installed to give fairly good picture quality.

One thing I forgot to mention was that the light-handling ability of some of the cheaper cameras is VERY poor.
I have returned several indoor cameras because they simply wash-out the scene when it becomes brightly lit - such as in full sunshine.
The moral here is to check before destroying the packaging !

Today I want to look at the first of the topics you should consider if you've decided to give Do-It-Yourself surveillance a go.
This topic is Should I Use Wireless or Wired security?

First of all, it needs to be said that no matter what type of system you install, they are all susceptible to intentional disruption.

There are a number of wireless based home security systems on the market.
Most reputable wireless units have jamming detection built into them, which will dial a monitoring service if radio-based interference is detected.
One I have personally found to be quite adequate for my purposes on small security installations, is the LYNX security system from ADEMCO.

Differences between the two types
The major differences between a wired and a wireless installation are that the sensors all need regular battery maintenance and that intrusion can be effected without having to actually enter the premises.

Obviously wireless installations lend themselves to difficult sites and also for speed and ease of installation. On the other hand the cost of the sensors is greater as too are battery maintenance costs.

Wired installations are conversely more difficult to interfere with because physical access is necessary. They also support cheaper sensors, although this can easily be offset by the cabling costs.
Wired installations also have the benefit of a central power source rather than having to maintain relatively expensive long-life batteries (often Nickel Metal Hydride) in a dozen different and often difficult-to-access places.

Special considerations for video installations
Where video surveillance is concerned, there are some additional issues which need to be considered.
The cameras still need a power source so they are NOT truly wire-less!

Because the publicly available wireless cameras operate on a public radio channel shared by many other devices and users, general non-malicious interference can cause such severe signal degradation as to render the image(s) useless. Also, because the signal is usually NOT encrypted, anyone within 100m can view what is being "seen" by the cameras.

Take care what the camera "sees"
This latter point may not be so bad in outside settings where no pattern of traffic is obvious nor anything of value visible. Within a building however, to monitor your heirlooms cabinet or your $10,000 home theatre equipment is rather like putting signs out within 100m of your premises to advertise what you have that's worth stealing!
Another thing that is forgotten when using wireless monitoring, is that your patterns of movement can be very accurately recorded so thieves know when you are likely to not be in a room or building.

Image Quality and Distance to Cameras
Picture quality and reliability is significantly superior with a cabled video system but does have distance limitations without signal repeaters.
Image quality is often more "noisy" with radio and also has distance limitations which are harder to overcome than with cable extenders.
My own experience with wireless cameras has shown that while 100m is possible with clear line-of-sight between the camera and the receiver, ANY obstacle will drastically degrade the distance/quality of transmission

Next installment I'll start talking about monitoring the devices and how they may connect.

If there is anything you disagree with me on, or want clarification about, please feel free to add comments

Premises security (part 2) Local vs Monitored also Use of Video Survellience

Local Security - continued from yesterday

With a "local" security system it may be possible to completely disable it, simply by removing the power for several hours !

If you're serious about electronic security, you really need to consider having a monitored system and/or some form of extended power supply. (More about power supply later)

The sad reality of unmonitored security systems is that by-and-large, audible and visible alerts will be ignored by the majority of people.
In Australia this problem is compounded by insufficient law enforcement officers for their timely attendance at any premises which may have an audible/visible alarm activated.

Before we move on in the topics, I'd like to share a little of my experience of "local alarm" security.

In one of my past lives, I was a registered security consultant and so got to see a wide variety of installations, ranging from the 'el-cheap-o' to the 'no-expense-spared' solutions.

In my opinion the best sort of "local" electronic security is made up of a mix of 'perimeter breach' and 'recorded digital video'.

Maybe at this juncture I should clarify what I mean by 'perimeter security', for those who are unfamiliar with these terms.

This first category, Perimeter Detection is often made up of some form of electronic security device(s) placed in the path of likely points of entry.

These devices are many and varied in today's digital security world, but some of the long-time favorites include:

• Door and window closure detectors which send a signal back to the control panel when the access-point is opened.
• Glass breakage detection
• Pressure mats in passageways
• Infra-red (invisible light) beams across access-ways.

These devices all detect a physical breach of the premises.
Damage has been done, (break-in) and someone has actually entered the premises.

The second category of devices can be classified as 'state-change' detectors and may include electronic sensors which either monitor and record events, and/or send alerts about the movement of a body or change of state within a monitored area.

These devices may include the likes-of:

• Passive infra-red movement detectors
• Proximity detectors
• Infra-red beams may also fall into this category
• In specialised installations, even things like moisture or noise detection may be used to monitor the security of the premises.
• Digital Electronic Security Cameras

Security Cameras

One of the technologies which has become affordable to the masses in recent times, is the use of digital electronic video recording.
The potential advantage of this type of security is that even if property is lost or damaged, with possible visual identification of the perpetrators, there is an increased likelihood of both recovering stolen goods, and of damages recovery.

As I said at the start of todays page,
The sad reality of unmonitored security systems is that by-and-large, audible and visible alerts will be ignored by the majority of people.

Recording Methods for Digital Security Cameras

With the minimal cost of large volume disk storage, this is probably the most common media for storing recorded security video.

Prior to the decreased costs and increased capacities of disks, the most common medium was the digital video tape, mainly because of the volume of data which could be stored on a single tape. The emerging option is to write the data directly to DVD.

Although I may dedicate more detail to it in a later blog, I'll just touch on it in this bit about cameras.

SWANN make a couple of quite reasonable little indoor/outdoor cameras for around the A$230~$250 mark
At the time I write this Dick Smith is selling them as shown on these links:
Wireless: L5980
Wired: L5981

ZTV make quite a robust indoor/outdoor wireless security camera range and matched receiver.
ZTV are now associated with AEE who market their products.
In Aust dollars these sell for around $250 each, so for a couple of cameras and receiver you'll only have to spend around $750. (That's pretty cheap for video security)
At the time I write this Jaycar is selling them as shown on these links:
CAT. NO. QC3564

As I said, I'll talk more about the pros and cons of wireless security in a later blog.

In future installments, I'll cover off setting up video security using your home computer and also the ability to remote-monitor your site via the internet.
I also want to mention the potential risks of doing that (remote monitoring).

Enough for tonight.
Hope you'll join me again for the next installment.

Premises security (part 1) System Types

If any of you have had any experience with security alarms for your home or workplace, you will no doubt be aware that the control panel and sometimes a remote sounder or strobe light will often have batteries fitted to them.
These batteries are often rechargeable cells which are recharged while mains electricity is supplied to the control panel. In the event of power loss, these batteries should maintain the operation of the security system until power is restored.

There are a couple of points to consider here.

The first is that there is always a trade-off of cost & size vs functionality, risk and aesthetics.

What I mean by this is that the designers can EITHER make a very robust electronic security system which will run without an external power source, for days on end, and allow for the added demand of an attempted break-in while STILL preserving the integrity of the system.
OR
They can build a neat little wall mounted unit which has lots of electronic "features" ... and a small rechargeable battery "in-case-of" power failure.

For the first design, we probably wind up with a fairly bulky (large storage-capacity batteries are not known for their lightweight & compact design), and probably not a very sexy looking system, which costs a lot and takes a large site to install in.

For the second design, the opposite is true.
Small, sleek, easy to install almost anywhere, and doesn't cost anywhere near as much.

The down-side to this, is that in a planned intrusion (such as while you are on vacation), power can be removed from your premises sufficiently in advance to allow the system to become inoperative.

In the case of many of the smaller Do-It-Yourself security kits, the internal backup battery may only support the system for between 2 and 8 hours.

Fortunately, most electronic security panels now-a-days have some "intelligence" built into them!

At this point, I should digress long enough just to ensure that everyone understands that there are a number of basic types of security installation:

1. At the top of the scale you have the site which has full closed-circuit electronic video camera surveillance and perimeter intrusion detection, backed-up by on-site security guards monitoring the cameras and doing physical checks on a random basis.

2. Next rung down might be the site which has full closed-circuit electronic video camera surveillance and perimeter intrusion detection being reported back to an off-site security monitoring center.

3. Down another rung the site might only have one or other of video or perimeter protection reported back to an off-site security monitoring center.

These first three examples are what is known as "monitored" or "back-to-base" security systems

4. Another step down might be the site which has full closed-circuit electronic video camera surveillance and perimeter intrusion detection, but no off-site monitoring, only a local siren and possibly a flashing strobe to draw attention.

5. Getting towards the bottom of the scale is the site which has only one or other of video or perimeter protection with no off-site monitoring. Perimeter-only detection probably being the most basic alarm system anyone would install

These latter two examples are what is known as "local alarm" systems.

With "local" systems, there are again several sub-categories.
1. You have the audible and/or visible deterrent type of system.
2. You have the video capture system where video security cameras record to digital data storage such as disk, DVD, or videotape.

While obviously there are many permutations of video vs perimeter, with/without physical site patrols/guards, local alerts vs monitored systems, for the purpose of this topic, suffice to say there are the two categories of Local vs Monitored systems

If your system is a "monitored" system, then when external power is lost, the unit may call the monitoring centre after a period of time. Failing this, when the battery nears exhaustion, a "battery low" warning may be sent to the control centre.

If your system is "local alarm", meaning there is no external monitoring, guess what happens ?

(Part 2)