Bi-mode (Solar-115VAC input) 12V battery charger

[francoisB]

I am doing a small cellular transceiver that needs to work from AC 115V input or from solar panels (in the case of 115V failure), and on battery during nights and cloudy period.
Working Temperature range: -40C to +50C
Charging current between 2 and 10 amps on a 12V gel cell type
minimum : 3 stages charger

Does this charger exist?

Else, can a simple adaptor circuit "AC115V to DC18V" feed a standard solar MPPT charger using the solar panel input ? Does such device exist ?

Please, let me know

[adoublee]

-40C? You sure?

[J.P.M.]

-40C? You sure?

A typo . Actually -40 F.

[jflorey2]

A typo . Actually -40 F.

Very funny!

[J.P.M.]

Very funny!

Only for those who know why.

Worst case: No harm done.

[adoublee]

How about 233.15K

[SunEagle]

A typo . Actually -40 F.

Actually I have seen that -40C requirement before. My guess it is for use somewhere in the Alps or high mountain region.

[J.P.M.]

How about 233.15K

Works for me. Just as accurate as the other two.

[Sunking]

only for those who know why.

-40 f = -40 c

Did not fool me.

[Sunking]

I am doing a small cellular transceiver that needs to work from AC 115V input or from solar panels (in the case of 115V failure), and on battery during nights and cloudy period.
Working Temperature range: -40C to +50C
Charging current between 2 and 10 amps on a 12V gel cell type
minimum : 3 stages charger

Does this charger exist?

Yes hundreds of them.

[J.P.M.]

-40 f = -40 c

Did not fool me.

I never entertain futile aspirations. You're just too smart for me ! in any case, still P.F.C.

[Sunking]

I never entertain futile aspirations. You're just too smart for me ! in any case, still P.F.C.

Nah you fool me sometimes. SNAFU

[jflorey2]

Actually I have seen that -40C requirement before. My guess it is for use somewhere in the Alps or high mountain region.

Story time -

We were doing a 300 way record attempt in December 2002 in Arizona. One morning we started at 6am; ground temps were about 20 degrees F. The temperatures at exit altitude (~24,000 feet) were -37F. One of the guys in my plane was from Germany and he asked me what that was in degrees C. "About -37C" I told him. He looked at me funny, like I was pulling his leg.

We got to altitude and exited. I remember breathing in, breathing out and bam - my faceplate froze solid, completely white. I was "lucky" in that my old helmet had a narrow gap between the top of the faceplate and the helmet itself, so I could look through the gap to navigate through traffic. Other people had to take their helmets off - which didn't help too much, because your eyes aren't much good in 120mph of -37F wind.

Fortunately no one got hurt and we landed safely. For the next half hour helmets hit the ground all over the airport (and in the nearby town.) We all switched to goggles with anti-fog on them, which worked for visibility, but not so much for frostbite prevention.

[bcroe]

A typo . Actually -40 F.

Its a test.

[PNPmacnab]

"feed a standard solar MPPT charger using the solar panel input ?"

And it has to be cheap. I'm trying to imagine a remote cold location that already has 120V AC and still needs a solar panel. That said if the controller is MPPT, The panel could be isolated with a diode and a simple transformer rectifier supply at below the expected MPPT voltage would smoothly transition into powering the charge controller when clouds occured and the panels could not supply enough power.