Diving torch

[Siman_196]

Hi, Please forgive me as I am a newbie, i also have limited electronics

experience.


I hope anyone will be able to help me??
I have built myself a diving torch, The design is an umibilical system,

there are no external switches. To turn the torch on the handle rotates

which operates a reed switch which is place internally. This is
connected to a relay which turns on the lamp.


I would like to improve this with a self monitoring circuit which will
dim the light by 50% when the battery voltage reaches 50% of the
operating voltage.(Hope that makes sense??).
I would also like the lamp to flash (approx 5 - 6 times) when the
voltage of the battery reaches the minimal voltage allowable(As
specified by the manufacture) then it switches off until the batteries
are fully charged.
Attached to the circuit I would like to have a push button to determine

the battery status when the case is open, ideally via 3 off leds??
Green - Good
Amber - Medium
Red - Low


Here are the details of the torch:-


Batteries - 2 x 12V 3.2Ahr seal Lead acid
Lamp - Halogen 12V 75W
Reed switch in the umbilical torch


Regards


Simian_196

 

[ehsjr]

Hi, Please forgive me as I am a newbie, i also have limited electronics

experience.


I hope anyone will be able to help me??
I have built myself a diving torch, The design is an umibilical system,

there are no external switches. To turn the torch on the handle rotates

which operates a reed switch which is place internally. This is
connected to a relay which turns on the lamp.


I would like to improve this with a self monitoring circuit which will
dim the light by 50% when the battery voltage reaches 50% of the
operating voltage.(Hope that makes sense??).
I would also like the lamp to flash (approx 5 - 6 times) when the
voltage of the battery reaches the minimal voltage allowable(As
specified by the manufacture) then it switches off until the batteries
are fully charged.
Attached to the circuit I would like to have a push button to determine

the battery status when the case is open, ideally via 3 off leds??
Green - Good
Amber - Medium
Red - Low


Here are the details of the torch:-


Batteries - 2 x 12V 3.2Ahr seal Lead acid
Lamp - Halogen 12V 75W
Reed switch in the umbilical torch


Regards


Simian_196

I'm not a diver, but the requirements don't make sense
to me. It seems like you would be letting the state of
the batteries' charge influence the diving experience.
For example, you been under for 20 minutes and have 20
minutes of air left when your torch decreases the light
output by 50 %. Now you can't see as well. Do you want
that to happen, or would you prefer to have full output
from the light during the dive? Worse - you are down
for a period, your light flashes and quits completely
because of your requirement for the electronic design.
Might that lead to disaster? Again - I'm not a diver,
but it sounds like you would put technology in control
when it could be life threatening.

It seems wrong to me to take technology with you on a dive
that won't last as long as the dive was planned for. My
answer is to forget modifying the light the way you posted.
Instead, design it to last for the full period of your longest
duration dive, plus some safety margin.

Ed

 

[Quack]

I have to agree with Ed.

I do some recreational diving, including night dives, I would hate my
torch to flash a few times and switch off just because of the
manufacturers battery specifications (assuming i was silly enough to go
night diving without charging the batteries). I would prefer to use it
until it no longer operates at all, damaging the battery or not, as
once your down there you care about your life far more than that of
your batteries

The original description sounds fine, the only thing you might add
would be the suggested battery meter.

Alex.