Drysuit heating controller options

[Richard Dayan]

The main challenge is that many (most?) divers already have the batteries which run at around 14.4 or supposedly 12 volts (which is actually 11V).

Having a DC to DC converter could give a constant output with a variable input.

One other small feature: you must be able to replace the E/O connector cables during the life of the converter -- they are almost guaranteed to break if folded, etc.

It's possible to make an in-line dc to dc converter, to plug into the battery but I didn't need it in practice. Also lithium ion has these problems more than LFP batteries.

 

[Wibble]

Commercially you may want to think about that as it won’t add much to your build costs but it will get you a wider market.

Batteries are by far and away the most expensive part of a drysuit heating system. Extending the life of an older battery is a good saving. Also many of us own the not quite 12V Light-for-Me heater batteries. 18AH but around 11V or lower. A change of battery is $$$$, well over a grand. Stomping up, say, $300 for a controller that would make the thing work makes great economic sense.

BTW I’ve two of those heater batteries.

Another feature could be a switching function for, say, 2 inputs and two outputs means being able to use two batteries on long dives without wet-swapping the E/O cables and also run two heating circuits — e.g. suit and gloves

 

[Richard Dayan]

Commercially you may want to think about that as it won’t add much to your build costs but it will get you a wider market.

Batteries are by far and away the most expensive part of a drysuit heating system. Extending the life of an older battery is a good saving. Also many of us own the not quite 12V Light-for-Me heater batteries. 18AH but around 11V or lower. A change of battery is $$$$, well over a grand. Stomping up, say, $300 for a controller that would make the thing work makes great economic sense.

BTW I’ve two of those heater batteries.

Another feature could be a switching function for, say, 2 inputs and two outputs means being able to use two batteries on long dives without wet-swapping the E/O cables and also run two heating circuits — e.g. suit and gloves

I will be making batteries also, including a budget battery for $500.

 

[Wibble]

I will be making batteries also, including a budget battery for $500.

Then please look into doing something like using a power tool battery housing. Those are 18V/20V and cheap due to the volume they make. Back to that DC to DC converter again!

The point about power tool batteries is you can get them pretty much anywhere, even rent them. Flying ceases to be an issue if you can get them at the destination.

 

[grantmac]

A power tool battery canister would be pretty slick.

 

[Richard Dayan]

What we want is a system that can keep us warm and comfortable in any water temperature and is reliable and travel friendly. We want to buy just one system that can handle anything, last for at least 10 years, never breaks, is low maintenance and can come with us on trips. Thats is the goal.