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Re: [PSUBS-MAILIST] 12 Volt Solenoids

Bill,
 
I'm sure your not going to find more bang for your buck then with regular, off the shelf, lead acid batteries.  And, I know you'll find them in a diameter that will fit in a 12 inch pipe.  What you have to decide is, are you going to find yourself in a position that is likely to spill acid out of the batteries and are you going to be able to vent your battery pods every time your charging them?  If spillage isn't a problem and you can vent, go with the deep cycle lead acid. 
 
I doubt you'll find 24 volt batteries, and if you do, they won't be cheaper then two 12s.  Using two separate 24 volt circuits is a good idea.  You can draw one down to half and switch to the second, then draw it half way down, and still know you have reserve.  Any battery dealer should be able to tell you how long his batteries will run your motor at it's rated current draw.  Don't rely on guessing friends.
 
You'll find that, under water, your hardly ever going to run your thruster at full power.  Even more so, if your in "pea soup" like water.  You just can't see to go that fast.  Where you might use a heavy power draw is surfaced going to and from a dive site.  You have to decide if your going to be towed to a dive site or maybe be diving close to where you put in at.  If so, you'll dive all day and use the equivalent of an hour or two of total power draw. 
 
Those sealed auto type relays are great for your application.  I rebuilt the side thruster controls for "Persistence" using them.  They're quieter and more reliable then the open type relays I originally used.  McMaster Carr has a good selection of them at a good price.  If you don't have their catalog, do a search for them on the web. 
 
These are enclosed relays so there is no visible spark but I still wouldn't put them in a pod with a battery.  I'm sure they aren't rated as explosion proof.  Keep in mind that even a battery in it's normal use isn't explosion proof.  Your pod cap should be fixed in a manner that it's the weakest link in a pod explosion so it can blow off in a direction not facing you.  The concussion of a pod explosion would be bad enough.  It's rare but does happen. 
 
You will need more then one relay if your going to switch from forward to reverse and maybe to switch from one bank of batteries to another.    The thing to avoid is a situation where one relay is energized and it's possibility to energize an second relay reversing the power which will create a dead short across the batteries. 
 
If you could switch battery banks mechanically it would be better.  Maybe a rotary switch sealed in a pod.  They're made for campers and the like that have two battery setups.  Automotive type places should be able to get them for you.
 
You do defiantly need a speed controller.  You can pulse your motors on and off and also, as you said, run them on half power but if your visibility isn't good, you'll have times when you want to go real slow.  A dead man is a good idea but you could incorporate that in some other way.  I would see if Minkota has a rotary type controller that will work with your motor or maybe purchase some kind on the net that will.  A rotary controller is really easy to work into a housing with a waterproof O-ring shaft seal.  I don't think a trigger switch from a drill will do what you want anyway. 
 
First figure out what controller you can find that will work and you can make water tight.  Then you can decide if you have to go with the 12 - 24 volt controls or not.  After that I'll help you arrange the wiring if you still need.
 
I think I addressed all your questions.  If I missed something just ask again.  If you list the questions, they would be easier to answer one by one.
 
Happy parts hunting, Dan H.
 
----- Original Message -----
From: Akins
Sent: Thursday, October 20, 2005 7:03 AM
Subject: Re: [PSUBS-MAILIST] 12 Volt Solenoids

Hi Dan.
 
Thanks for responding. I need the help. Yes, you are right, I was thinking of using the car solenoids. Are there better ones to use than those? I have the basic idea of what I want to do and somewhat how to do it, but
 
I do not know exactly what amps, volts, etc to use. I'm not sure I could draw up a clear picture of what I want to do Dan, I'm not really sure how to do what I want to do to be able to draw a picture of it Lol!  
 
But generally speaking I was thinking of this......
 
I would like to find out if there are better batteries to use than standard lead acid deep cycle marine batteries that are not cost prohibitive. I was thinking of using four small 12 volt sea scooter batteries and connect them in
 
SEPERATE pairs in series so each pair put out 24 volts. One pair being for backup. But friends have told me my 74lbs thrust minnkota would eat up the electricity a lot faster than my sea doo sea scooter does,
 
and they said those small size batteries would not last very long at all driving the big minnkota. That makes sense to me, but I just don't know and am not sure what kind of batteries to get for sure.
 
From past threads at psubs, I have heard members say you cannot beat a regular deep cycle marine battery for cost compared to some of the newer gel types. Are deep cycle marine batteries that are 24 volts
 
and will fit into my 12 inch diameter pvc battery pod even made or will I have to go with the 12 volt ones? I'm not really up on types of batteries out there..
 
First I need to find out if I can purchase 24 volt deep cycle marine batteries that would fit in my 12 in diameter pod. If I can, I will use two. If not, I will use four 12 volt batteries and
 
connect two SEPERATE pairs of them together in series. That way I will have two 12 volt batteries making 24 volts to use to begin the dive with, and if they run dry, I will have another
 
pair just like the first, to come back on. I would like to have a variable speed control switch if possible, but if a waterproof one is not available or I can't rig a speciality tool, explosion proof (sparkless)
 
variable speed drill switch, to be waterproof, then I will just use toggle switches that have a rubber boot on the front and encase the back terminals in a silicon blob for waterproofing. A variable speed
 
trigger switch with a reverse setting would be the ultimate ticket. A trigger switch like that would also act as a "dead mans" switch, so the switch would not be able to run the motor without someone holding it down, just like
 
my sea doo scooter does. Otherwise, I have to use the toggle switches and that means one position for batteries off, another position for 12 volts at half speed, another position
 
for 24 volts at full speed and another position for reverse. Not the optimum choice and just two speeds. The batteries will be enclosed in my 12 inch pvc pipe with removable end cap and "O" ring mounted on the keel.
 
The solenoid could be in another smaller pvc pipe seperate from the batteries to make sure no sparks from the solenoid could possibly ignite any hydrogen from the batteries. Are there sparkless solenoids available that would
 
enable me to just put the solenoid into the 12 inch pvc battery pod? I don't know if I need seperate solenoids for each function of the switches or not. I am not very versed in electrical hookups but if I had someone explain exactly
 
what to do, I could do that. I also would encase all wire ends in epoxy to preclude any hydrogen from seeping thru the battery wires to the solenoid compartment.
 
That's pretty much my rough plan Dan. Sorry for the encyclopedia. There was no quick way to tell it. I haven't even touched on whether I should oil fill or air compensate my motor, also whether I should use BCD bladders
 
in the bow and stern for buoyancy and trim or if I should just centrally locate 4 or 6 inch pvc pipes along the upper side of the sub for buoyancy or even if I should just make the sub always very slightly buoyant and just use my
 
personal BCD to change attitude when submerged.  It is complicated by the fact that it is a TWO person cockpit wetsub but sometimes I may be diving it alone which would change the center of gravity.
 
But the buoyancy and motor pressure equalization questions I will leave for now until I get the batteries and wiring figured out first. Thanks again for your kind offer of help.
 
What do you advise?
 
Bill.
 
 
----- Original Message -----
From: Dan H.
Sent: Wednesday, October 19, 2005 10:55 PM
Subject: Re: [PSUBS-MAILIST] 12 Volt Solenoids

Bill,
 
The main difference in a 12 volt solenoid and a 24 volt solenoid is the voltage it takes to operate the coil.  The coil has to be operated with the proper voltage.  The contacts of the relay are more current sensitive then voltage sensitive.  As long as your relay current rating is as high or higher then the current (amps) draw of your motor, use it.  I assume your talking about the can type solenoids like the auto industry uses for car starters.  Correct? 
 
If you send me a pic of what you planning to do, I may be able to help you come up with some wiring ideas.
 
Dan H.
----- Original Message -----
From: Akins
Sent: Wednesday, October 19, 2005 4:33 PM
Subject: Re: [PSUBS-MAILIST] U505 gets historically correct paint.

Hi Ray.
 
I know what you mean. As a diver in Florida in our mucky gulf, I've gotten used to the "Viz" as we call visibility,
 
being less than adequate. There are times I have been unable to see beyond several feet because of the silty muck.
 
I agree with you that the phosphorescent paint could help inside our subs. I also like John Gaertner's point about the LED's
 
and the low voltage light they give. The higher end dive lights are all going to led's now. I think the best thing would be to have
 
both the phosphorescent paint and the LED's. When it is time to paint my wetsub, I might opt for phosphorescent yellow paint
 
so it could be seen better underwater. Speaking of my wetsub, I am still hoping to get advice on how to hook up my dash switches
 
to the solenoid and then to the batteries. Not sure if I can use a 12 volt solenoid for the 24 volt motor or not. Still need help in figuring
 
out how to hook it all up now that I've mounted the motor. Anyone have advice?
 
Bill.
 
 
----- Original Message -----
From: Ray Keefer
Sent: Wednesday, October 19, 2005 1:33 PM
Subject: Re: [PSUBS-MAILIST] U505 gets historically correct paint.

Hi Bill,

The bit about "phosphorescent coat" got me thinking.

Critical knobs and switches in our PSUB'S could
benifit from such a coating. I found out during my
submersible pilot training it can get unexpectedly
dark. Surprising how dark it gets driving into muck
stirred off the bottom. Even at only 15 feet down!

Regards,
Ray

--- Akins <lakins1@tampabay.rr.com> wrote:

> U505 gets the historically correct paint inside and
> out. Wooden decking gets correct preservative also.
> Bill.
>
>
http://www.nace.org/nace/content/library/articles/features/uboat.asp





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