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Amp-hour drain of 2kw radar?

Old 09-06-2011, 07:52 AM
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Default Amp-hour drain of 2kw radar?

I am getting ready to put a new electronics suite in my 34 cc, and am calculating the overall amp-hour draw from my batteries I will have when not running the motors. Not too big an issue when sitting over a wreck/reef for an hour or two, but I want to make sure I'll have enough juice to start the motors after drifting/anchoring overnight running the radar, under-gunnel lights, livewell, stereo, etc... I have the basic power requirements for everything but the radar. I have checked the websites for Lowrance and Garmin, but cannot find an amp draw for them anywhere.
Anybody know?
Thanks.
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Old 09-06-2011, 08:27 AM
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Your radar, and all other electronics should NOT be connected to the same battery that is used to start your motors. Make a house battery bank, and connect all your electronics to that bank, and leave your starting battery to do nothing but, start the motor. ;-)
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Old 09-07-2011, 12:48 PM
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Suggest you go to the mfgrs site for the radar you have or are looking at and check the specs for that particular unit.

For instance, a stand alone Furuno 1715 2.2KW LCD radar specs 38 W max while transmitting down to 8 W in watchman mode. Divide by 12 v and get 3.1A/o.66A. Older CRT units would demand more.
http://www.furuno.com/en/business_pr...rine/m1715.pdf

A combi system would likely take more battery power to run all functions rather than just radar., but perhaps less than the sum of amps to similar package of standalones, if they were all left running. I turn off everything not truly necessary when engines are off for more than a few minutes and I do have a dedicated 3rd battery for house/electornics.. The more you pull down the house battery the longer it takes to recharge.
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Old 09-08-2011, 09:18 AM
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Thanks,
I've actually found a lot more information since posting this question, and specifically found a diagram drawn by Birdman on another thread that just solved all of my questions. This is how I will re-wire everything and I think I should be all set.
Thanks Birdman for the great diagram
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Old 09-08-2011, 09:21 AM
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Welcome. Now you can drain you house down to nothing.... don't even need to think about it. If the hosue goes dead, simply start 1 or both motors to start charging it again. Both start motors will be at 100%.
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