The Time Lapse VCR is the one item in any system requiring the most maintenance. It is a mechanical menace, coupled to a CPU based controller and most often, left forgotten in a hostile environment (the average office). Time Lapse recorders are however the backbone of most CCTV systems and you do need them. So here’s a couple of tips on how to convert that monster to the user-friendly tool it really is.
The first step is to be sure of a good start. Reset your Time Lapse VCR as soon as it’s installed, before you start programming it. This will assure you the unit is set to factory default and none of its many software features are corrupted. The reset (or initialization) procedure is almost always found in the owner’s manual. Take a few minutes the night before an install to familiarize yourself with all of the unit’s features. Most Time Lapse VCR’s have a reset button. If you can’t locate it in the manual contact the manufacturer’s authorized service centre or the manufacturer directly, don’t call on sales, as they most likely will have to call service for the correct method. Another important tip is to always, after an interruption of power, reset the unit again.
The next step is to be sure that you have provided your client with a fresh batch of new video cassettes (I prefer the T120 size) and a good rotation system such as 7 or 31 days (see table below). The usage varies depending on the recording speed selected. Example if you are recording at the 24Hr. speed the tapes should be replaced every 20 passes (a pass being 1 start to finish), and if you are using a « one shot » alarm recording regardless of the speed replace them after only 2 passes.
TAPE USAGE TABLE
|Record Time (Hours)
|360 to 999
|Pause / One Shot
As for the brand to use, they are many makes out there, purchase a name you recognize (video cassettes not camera film) and use only a standard tape. Don’t get hooked by all of the marketing claims on every cassette you see, they are directed to the consumer market not the security field. Any tape with a high metal content will wear out your video heads before their time. Its very important to inform your clients to use only the cassettes you have provided and never under any circumstances use the Time Lapse to view a movie or any promotional material unless its new out of a wrapper and has never been inserted into another VCR. Many times we have received Time Lapse VCR’s with a promotional cassette stuck inside, and the reason it was stuck was due to contamination to the tape path from an outside source. Much to client’s dismay all of the rotation tapes had to be replaced in the chance the contamination had (through the Time Lapse) spread to them. Advise your client to purchase a $99.00 consumer special if they require a unit to view anything other than their security tapes.
The point of installation is a good time to discuss with your client a service contract. Explain to your clients that the average Time Lapse recorder sees more usage in 1 year as does their home unit in 10 (show them the math), and its very important to « maintain » them, I call this « preventative maintenance ». All Time Lapse recorders require their heads to be replaced between 8,000 ~ 12,000 hours of accumulated use. This is the time the head is actually being used and not with the equipment just idling on standby. SVHS and High Density « Real Time » units will probably (and do) require the replacement sooner than the traditional Time Lapse unit. The reason for the differences is as follows, the SVHS video cassettes have a much higher metal content than « normal » tapes and that abrades the video heads sooner. As for the High Density units, their heads are much thinner and wear faster.
A worn head exhibits a reduction of signal strength, which is almost impossible to notice with a naked eye, but when you attempt to digitize the output, you will clearly see the difference. The whole idea of a Time Lapse recorder is for surveillance, why bother if you can’t obtain a clear « picture » for evidence. Multiplexers also digitize and encode the signal and with weak heads you will have a fit trying to decode (play) the tape.
When a unit is taken off duty to have its heads replaced, it’s a good time to have it « overhauled ». If the unit has 10,000 hours on it, you can be sure it will need some mechanical work to get it through another 10,000 hours of uninterrupted service. Usually the cost is not that much more than the head job to have peace of mind and save on nuisance repeat service calls.
My next piece of advice concerns the use of Time Lapse VCR’s as event recorders. As most of you know, Time Lapse recorders have an alarm input that can be used to trigger the recording process through the closing of a contact. The most common setup is to have the Time Lapse on standby mode and to start recording during an « alarm ». This puts the Time Lapse’s mechanics through the most difficult and potently damaging usage imaginable…. stop, start, stop, start and so on. Most Time Lapse recorders on the market today would have difficulty in surviving up to the first 10,000-hour maintenance schedule. Not to mention, cassette replacement is recommended after only 2 cycles in that particular mode. A much better way is to setup the recorder to record at a nice slow speed 24 up to 960 hours and when it receives an alarm, speed up to the 2-hour mode. You will also gain that extra recording time lost when the recorder « wakes up » and starts to record from stop in the previous mode. Think of it like any automobile, downtown driving only, or cruising along the highway, speeding up to pass once and a while. Which car will require costly repairs sooner?