# Inductors?*!

R

#### Raveninghorde

Jan 1, 1970
0
Anyone know a good supplier of off the shelf inductors?

I'm doing a battery charger design using a sepic converter. Got a daft
spec to meet of -55C storage with 0C to 45C operation.

All the specs I've checked give -40C for storage though one from
Coilcraft also gave -55C for operation??

I've tried Coiltronics, Coilcraft and Weurth.

P

#### Phil Allison

Jan 1, 1970
0
"Raveninghorde"
I'm doing a battery charger design using a sepic converter. Got a daft
spec to meet of -55C storage with 0C to 45C operation.

** Seems to me that even a well performing PSU might be damaged by
attempting to use it when its temp is -55C.

Better fit something that DISABLES the unit whenever the internal temp is
to low for safe operation - like a normally open bi-metal switch that
closes at 0C.

..... Phil

S

#### Spehro Pefhany

Jan 1, 1970
0
Not necessarily daft -- -55C storage is a pretty common mil spec
requirement; it comes from (I think) high-altitude unheated cargo bays.

The only thing that surprises me is that it isn't coupled with a -40C
operating spec, which is the usual MIL-SPEC system lower limit.

Could be limited by the battery rating.
At any rate, there should be parts out there, although they may cost .

Best regards,
Spehro Pefhany

R

#### Raveninghorde

Jan 1, 1970
0
Could be limited by the battery rating.

Best regards,
Spehro Pefhany

Many military batteries charge below 0C. For example Saft do some NiCd
cells which can be charged at -40C and are used in some UK batteries.

I found API Delevan do some standard inductors that will work.
Unfortunately I haven't found a coupled sepic inductor yet.

P

#### Phil Allison

Jan 1, 1970
0
"Raveninghorde"
Many military batteries charge below 0C. For example Saft do some NiCd
cells which can be charged at -40C and are used in some UK batteries.

** Kindly provide a link for that assertion - pal .

Since AFAIK it is IMPOSSIBLE to recharge a NiCd cell at a temp below
zero C.

Cos the little fuckers have got a crucial, tiny bit of water inside them
which MUST be in the liquid state.

Over to YOU ...

..... Phil

R

#### Raveninghorde

Jan 1, 1970
0
BTW pure water will supercool a surprisingly long way if it is free from
dust, but I would not want to rely on that. The electrolyte is caustic
potash which has a significantly lower freezing point.

Dissolved caustic potash depresses the freezing point of the water.
48% potassium hydroxide in aqueous solution remains liquid down to about
-11C see for example BASF datasheet.

http://www.inorganics.basf.com/p02/...Laugen)/Produktinformationen/Kalilauge#N10122
(be a miracle if that link survives)

NASA and various motorways agencies have published data of specific
NiCad batteries behaving OK in service at temperatures down to -15C.
The electrolyte must be liquid enough for ions to be mobile - when water
starts to crystallise out the remaining caustic becomes stronger and
harder to freeze so some channels remain open for conduction. I expect
irreversible damage and leaks are possible if they are hard frozen.

BTW I too doubt NiCads will charge very well at -40C.

Regards,
Martin Brown

Having checked my facts, the battery I was thinking about is specified
to charge at -31C not -40C.

I'll add no more due to commercial sensitivity.

P

#### Phil Allison

Jan 1, 1970
0
"Martin Brown Just Shat Himself "
BTW pure water will supercool a surprisingly long way if it is free from
dust, but I would not want to rely on that. The electrolyte is caustic
potash which has a significantly lower freezing point.

Dissolved caustic potash depresses the freezing point of the water.

** Who give a flying **** ?????????????

you ridiculous MASTURBATING BLOODY IDIOT !!

ALL NiCd makers warn NOT to attempt charging cells below 0C

and the FUCKING STUPID PILES OF SHIT

FUCKING EXPLODE WHEN YOU TRY !!!!!!!!!!

- you pathetic, ASD fucked moron !!!!!!!!!!

..... Phil

P

#### Phil Allison

Jan 1, 1970
0
"Raveninghorde"
Having checked my facts, the battery I was thinking about is specified
to charge at -31C not -40C.

I'll add no more due to commercial sensitivity.

** Why don't lying, know nothing, fucking trolling CUNTS like YOU

just go and get totally fucked ??

Eh ??

... Phil

M

#### MooseFET

Jan 1, 1970
0
Anyone know a good supplier of off the shelf inductors?

I'm doing a battery charger design using a sepic converter. Got a daft
spec to meet of -55C storage with 0C to 45C operation.

All the specs I've checked give  -40C for storage though one from
Coilcraft also gave -55C for operation??

I've tried Coiltronics, Coilcraft and Weurth.

Try www.picoelectronics.com. I used some from them many years back
that were inductors with two windings. You may have to work a little
at getting a full spec sheet from them.

R

#### Raveninghorde

Jan 1, 1970
0
"Raveninghorde"

** Why don't lying, know nothing,
SNIP

Eh ??

.. Phil

Public info here:

http://www.dstan.mod.uk/data/61/021/00000119.pdf

Section 25. 50 charge/discharge cycles. Test at -31C.

Section 17.4 states charger at 20C, battery at test temperature, max
charge time 5 hours.

That's a battery for a 1980's radio.

The batteries are available on Ebay if you want to see how they are

P

#### PeterD

Jan 1, 1970
0
"Raveninghorde"

** Seems to me that even a well performing PSU might be damaged by
attempting to use it when its temp is -55C.

Better fit something that DISABLES the unit whenever the internal temp is
to low for safe operation - like a normally open bi-metal switch that
closes at 0C.

.... Phil

Or build in a small heater to keep the internal temperature above the
'magic' number! Lucky for you, in Oz, it never gets that cold! <g>

P

#### Phil Allison

Jan 1, 1970
0
"Tim Wescott Moronic Wanker "

** That page, plus what is on page 9, backs up * 100% * what I posted here

NiCd cells must not be charged below 0C.

Do you know _anything_ useful,

** Hey - YOU ASININE FUCKING IDIOT .

YOU are so mind numbingly fucking stupid

- YOU cannot even read simple data sheet.

...... Phil

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