Oakld

Hello all, I can use advices on this topic, since I have little experience with CCTV and I don't even trust local shops to be able to supply what I need. I need to optimize camera system in terms of minimum power supply, remote data saving and related to both previous points is optimized mode of operation. Last but not least, cost is also a parameter. Requirements: Isle operation - it will be installed on a remote objects with no electrical supply. The system will be powered by 12V DC acumulators (this is standard power supply of both cameras and control units) with assistance of solar "isle system" recharging. Especially from October till March the solar won't supply enough power and accumulators will have to be manually recharged by generator. So minimizing number of components and selecting an optimal mode of operation of cameras, especially in regard of IR LED lighting is a key to success Optimally 6 cameras with IR LED - the object is in open area accessible from all sides, we need 1 camera inside to keep eye on horses, this leaves 5 cameras for the outside, depending on angle view bearly covering the surroundings. If we use only 4 cameras, we'll have to add dummies to black spots. Snapshot mode of operation - to save power and internet traffic, best preferred method of operation seems to be a snapshot mode. Let's say, that in quiet mode, every 10 seconds a camera would do a snapshot and would stay turned off between the snapshots. A serious crack to this idea was a claim of a friend, that most cameras cannot turn of the IR (it's always on) and if you turn them on and off, it takes some time to focus them. So I'd really appreciate clarification how they behave and what's possible to achieve. Saving data - the data should be saved on the internet (i.e. FTP server, Dropbox, Google Disk, etc.). No monitor, mouse or keyboard will be on-site, setting and adjusting to be done over the internet (Linux and/or Windows and/or Android). Ideally, in case of detected potential threat, a more frequent snapshotting or continous recording should be engaged. In such cases, an alert in form of facebook message, google hangouts message or email or such would be a nice feature. The system will be connected to wireless internet connection with 500Kbps upload speed installed just for this purpose. Optionally saving to local medium as well, preferring an SD card over HD (due to power requirements) optionally, a connection to a motion sensors or complete small alarm system If I consider a system such as Evolveo Detective (http://www.evolveo.eu/en/detective_s4cih7d), then I believe the issues are: excessive components and features - higher power demand than required by what I need mode of operation - probably, supplied software won't allow to tune the system (cameras and data uploading) to a configuration with minimum power demands Another idea would be a small Linux router with scripts run by the router to turn on the cameras and save the snapshots over the internet. Of course, the best would be to point out to product, which is "off-shelve" and has low power demands. Thanks in advance for any useful suggestions. Regards, Oak

Hello, I got an interesting link to calculation software online, here are the results: So the previous calculation was about correct, the worst is actually December with poor 140 Wh a day. As for batteries, I made a mistake in calculation. One cannot add capacities of particular cells when they are connected in series. Correct capacity is then only 40 Ah * 12V * 0.8 = 384 Wh a day. Unfortunately I found none in the "local" internet shops sells NiFe batteries, so far... OK, I double checked the electrical work formulae: W [Wh] = U [V] * I [A] * t [hrs] = 12V * 0.26A * 24 hrs = 74.88 Wh. So you are right and that means that really, there's far not enough energy to power all the cameras, actually not even one half the night. I can actually state, that I have 1.3 A available in battery capacity for everything together (for 24hrs operation), which is terribly small current. It's not even enough to run the Athena and modem. As for wind generation, it was advised by my internet supplier, who does those installations for companies in water business (probes etc) in remote isolated areas. But really, it doesn't seem to be feasible here. There's very little wind available and to get some meaningful output from the wind generator, you need quite strong wind. A good generators start supply energy at very low wind speeds, however only fraction of their full power. So really, I'll have to optimize on all fronts. Possibly a completely geek setup will be required with linux PDA/phone type of controller (instead of recorder) and controlled cameras switching on/off? If I fail to create a feasible camera setup, I will have to consider a combination of a perimeter control (alarm with GSM connection rather then internet) and camera traps. BTW, does the CMOS chip in the camera need to be heated in winter by it's own continuous operation? Sad thing is, that I DO have to expect intruders . Thank you all for your comments! Regards Oak

Hello, technically speaking, yes, it is possible to harvest and store enough energy even for those cameras. But let's be realistic and assess a feasible system. Sorry for any mistakes bellow, I'm not an electrician. I'd be pleased to be corrected. Considering a feasible 200Wp panel (at cca 230 USD), it will do per day roughly 2Wh per Wp, which is 400 Wh per day (in central Europe, cca 120km north from Wiena). But this is going to be far less in winter months, roughly 160 to 180 Wh. Now this power has to be stored. Ordinary lead batteries, even those which claim to be "solar" are rubbish, as you cannot use more then 20% of the capacity, or you will destroy them very soon. So I consider a LiFePo4/LiFePoY4 batteries - more expensive, but excellent in draining and recharging. So 4 battery cells 3.2V, 40Ah @ 80USD will make a battery of 12.8V 160Ah at cost of 400USD (incl. balance unit). Let's consider an 80% efficiency, so we have 160 Ah * 12V * 0.8 = 1536 Wh a day. BTW I consider putting it into a plastic tube circa 1m bellow surface level to keep it in frost-free depth. Now, let's calculate the security system. Each camera with IR on (typically) needs 260mA power. In winter months, it will require 14hrs on (6pm to 8 am), so it's 0.26A * 12V = 3.12W a day per camera. If all 5 cameras would be on all the time, it's roughly 16W. Let's estimate the day operation to 4W for all cameras. So we need 14hrs * 16W + 10hrs * 4W = 296Wh. The recorder needs 3W power supply, so let's estimate it's power requirement to 1.5W --> 24hrs * 1.5W = 36Wh. Another roughly 3W will require internet modem with wireless antena --> 24hrs * 3W = 72Wh. Plus let's consider 4hrs of LED lights on @ 20W = 80 Wh In total it's 296 + 36 + 72 + 80 = 484Wh. So it's far less then stored energy and the difference should even accommodate some losses due to efficiency, and even more cameras can be added. Actually, this looks feasible, which I am surprised of. The calculations didn't work for me previously, because I considered lead batteries and far more consuming cameras (5W per camera + 2W per IR LED light), but here http://www.evolveo.eu/en/detective_s4cih7d (at the very bottom line) they state that the cameras have 260mA with IR LED on. So the selection of cameras will affect the system a lot, I suppose. And providing that I didn't make any cardinal mistake in calculations. There might be need for additional efficiency ratios, for instance. To complete costs for anyone interested: WiFi antena and modem one-time cost is 53 USD, monthly charge is 8.25 USD (a special offer for low download speed, but 500Kbps upload speed). Can someone say, whether my calculations are correct? Any practical experience? Regards, Oak