Quote:
Originally Posted by smac999
With 3 switches I ways put the parellel on the battery side of the main switches, so it can 't be isolated anyways. So it's the same ad the dual circuit. If a battery goes bad That is what a wrench is for.
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Sorry but isolation of a bank is of prime importance in any
good system design. Take a close look at the pre-wired Blue Sea three ON/OFF switch
panels, such as the 8280 or 8370, and the parallel is on the LOAD side of the switches so a bad bank can be 100% isolated and done so without wrenches. Perhaps you could
email Wayne and tell him he's wrong on this..
Quote:
Originally Posted by smac999
Putting the parellel switch on the load side is dangerous.
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You only created this "dangerousness" in your own mind. Putting it on the battery side is dangerous because it allows for zero isolation of a bad, internally shorted or faulty bank when the parallel switch is made, without physically disconnecting them with wrenches. There are many owners I would not trust with a hair brush let alone wrenches near batteries while at sea.. Putting it on the load side allows ALL options with the simple flip of a switch...
Quote:
Originally Posted by smac999
If I want an engine to go dead to work on it. The engine switch should 100% kill it.
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And it does unless the parallel switch is made and the HOUSE switch is ALSO made. If you were going to turn off the START switch you instead turn off the EMERGENCY PARALLEL and it achieves exactly the same isolation. But remember this EMERGENCY PARALLEL switch is for emergencies and would be a rare occurrence.
Quote:
Originally Posted by smac999
But in your case if the parrell is left on it won't be.
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Your argument is that you turn off the START or main battery switch to kill the engine to work on it.. Good practice and I agree 100%!
So in a situation where the start bank has failed (remember an emergency situation and rare) that switch is already OFF. Now you simply move your fingers 2" to the left and turn off the EMERGENCY PARALLEL switch and you are at the SAME PLACE having done the same exact thing isolating the engine. This is a straw mans argument if I ever heard one....
Quote:
Originally Posted by smac999
the chances of a battery going bad is smaller then someone turning a switch off and thinking a load is dead but is not.
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If you turn off the EMERGENCY switch, just as you would the START switch, the human movement and actions are EXACTLY the SAME. With the DCP you have to kill both banks to work on the engine. With the three switch you only kill the START. Unless there is an
emergency situation then you would turn off the EMERGENCY PARALLEL instead, to work on the engine.
I have seen many, many banks go bad. While rare it does happen. This is why smart folks like Wayne Kelsoe of Blue Sea Systems designed their three switch
panels with the parallel on the LOAD side, because they get it and understand that isolation of a bank is a critical feature to have, when it is possible.
Any good tech or boat owner checks what they are working on or kills all battery banks. Hell better than 70% of the cruising boats I work on have an alt fed direct to the house bank. The vast majority have been done by folks who don't install an alt
service disconnect.. In my installs I do install a clearly labeled engine room
service disconnect for the alt feed so teh alt is not live when you may not expect it to be..
Quote:
Originally Posted by smac999
The best would be a pair of 1-2-all switches feeding the house and engine. Then you can isolate and combine or power from either battery or both same battery. But that would be more confusing and lead to wrong selecting and draining
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You got that right.... Hell most folks can't even figure out a single 1/2/BOTH and now you want two of them.....