05-20-2007, 01:16 PM
I mentioned before that I have stopped using the lead acid, and gel cell batteries to provide power for the sonar in my tube.
Here is the information I based my decision on, and some pics and details of the setup that I now use.
First the power requirements. My sonar is an "old" Interphase matrix (now called "Probe") with scanning capability. It projects a narrow 12 degree beam to about 640 feet, then sweeps the beam, to draw my screen every pre-set interval, so I assume I have a 1500 watt peak to peak system here.
For the pictures I had inserted a device called a Wattmeter, in between the battery and my sonar, and this displays (clockwise starting top left)the amps being consumed, the battery voltage, watts drained so far since switching on, the watts (volts x amps)being consumed.
My Wattmeter shows that not everything is as you would expect in the sonar operation, and there are a few surprises.
Now ... the battery.
Although I worked my way through three of them over the years, I never liked the 7 amp hour gel cell. It is heavy enough to damage stuff if it falls, and it made my tube cumbersome, unbalanced and awkward to carry when loading and launching.
I wanted a lighter more compact battery than either lead-acid, or the gel cell alternative. So I am using three sizes of model airplane battery.
All are nickel metal hydride batteries (NIMH) with a conventional steel can on each individual cell that makes up the complete battery pack.
There is a newer, (more expensive) technology, called lithium polymer (LIPOLY) that a model suplier might try to sell you, but these are in a plastic covering, and can be permanently damaged by bending, puncture, or a deep drawdown, all of which happen from time to time in a tube. (Ok when protected in an appl;iance such as a mobile phone) So LIPOLY is not suitable for tubing.
I use the cheaper, steel plated, more robust NIMH.
The make of the cells are GP. Others are interesting, eg Sanyo, Panasonic, but GP are reliable and last as long as Gel cells.
I only use C or sub C cells (the fat ones) because the lighter AA cells are a bit more fragile and far slower to recharge.
These C cells can be fully recharged from my car battery in 30-40 minutes from empty.
The sonar is a 12 volt unit, so I want 12 volts. A single NIMH battery is 1.2 volts, so I use ten cell packs with a total voltage of 10 x 1.2V = 12 volts. there might be a tiny spark when pluggin the battery onto the sonar leads, so i power it off , plug the battery on, then switch on. I have never blown a fuse, but it is still in the wiring just in case.
The plugs are gold banana plugs, self cleaning during use, and put on in such a way as to prevent accidental plugging in with reverse polarity, something spade plugs will not prevent. The gold plate makes a good contact, so I consume lower power, and everything works better.
Here are three of the battery packs that I use ....
Also - the "old" 12V gel cell ...
[signature]
Here is the information I based my decision on, and some pics and details of the setup that I now use.
First the power requirements. My sonar is an "old" Interphase matrix (now called "Probe") with scanning capability. It projects a narrow 12 degree beam to about 640 feet, then sweeps the beam, to draw my screen every pre-set interval, so I assume I have a 1500 watt peak to peak system here.
For the pictures I had inserted a device called a Wattmeter, in between the battery and my sonar, and this displays (clockwise starting top left)the amps being consumed, the battery voltage, watts drained so far since switching on, the watts (volts x amps)being consumed.
My Wattmeter shows that not everything is as you would expect in the sonar operation, and there are a few surprises.
Now ... the battery.
Although I worked my way through three of them over the years, I never liked the 7 amp hour gel cell. It is heavy enough to damage stuff if it falls, and it made my tube cumbersome, unbalanced and awkward to carry when loading and launching.
I wanted a lighter more compact battery than either lead-acid, or the gel cell alternative. So I am using three sizes of model airplane battery.
All are nickel metal hydride batteries (NIMH) with a conventional steel can on each individual cell that makes up the complete battery pack.
There is a newer, (more expensive) technology, called lithium polymer (LIPOLY) that a model suplier might try to sell you, but these are in a plastic covering, and can be permanently damaged by bending, puncture, or a deep drawdown, all of which happen from time to time in a tube. (Ok when protected in an appl;iance such as a mobile phone) So LIPOLY is not suitable for tubing.
I use the cheaper, steel plated, more robust NIMH.
The make of the cells are GP. Others are interesting, eg Sanyo, Panasonic, but GP are reliable and last as long as Gel cells.
I only use C or sub C cells (the fat ones) because the lighter AA cells are a bit more fragile and far slower to recharge.
These C cells can be fully recharged from my car battery in 30-40 minutes from empty.
The sonar is a 12 volt unit, so I want 12 volts. A single NIMH battery is 1.2 volts, so I use ten cell packs with a total voltage of 10 x 1.2V = 12 volts. there might be a tiny spark when pluggin the battery onto the sonar leads, so i power it off , plug the battery on, then switch on. I have never blown a fuse, but it is still in the wiring just in case.
The plugs are gold banana plugs, self cleaning during use, and put on in such a way as to prevent accidental plugging in with reverse polarity, something spade plugs will not prevent. The gold plate makes a good contact, so I consume lower power, and everything works better.
Here are three of the battery packs that I use ....
Also - the "old" 12V gel cell ...
[signature]
