Can I Splice Resmed DC converter to Qi output cord?

[RichInBunlyGoodness]

I have a Resmed S9 I'd like to be able to power with my Qi Battery. Can I splice these together?

[chunkyfrog]

If it smokes, you should not have done it.

[palerider]

I have a Resmed S9 I'd like to be able to power with my Qi Battery. Can I splice these together?

try not getting those two unmarked bare wires backwards, that could be bad.

[Omne]

You can do anything, the question is whether it's a good idea. In this case it probably isn't.

I've been out of electronics for a long time but you're basically putting a battery with 4A max output into a converter (for whatever reason) that is designed for an input of 13A at 12V, or 7.8A at 20V. I'm going to guess that under load it's going to try and draw a lot more than 4A, in which case you're going to get a very hot battery and some damage when you try and run the Resmed. With no load it's just going to sit there.

YMMV

[palerider]

You can do anything, the question is whether it's a good idea. In this case it probably isn't.

I've been out of electronics for a long time but you're basically putting a battery with 4A max output into a converter (for whatever reason) that is designed for an input of 13A at 12V, or 7.8A at 20V. I'm going to guess that under load it's going to try and draw a lot more than 4A, in which case you're going to get a very hot battery and some damage when you try and run the Resmed. With no load it's just going to sit there.

YMMV

the converter is sized to run a humidifier and heated hose, without those, the load is much lower... it *could* work.

[Wulfman...]

What is it with all these people wanting to "reinvent" things???
It's been going on for years and another batch of them here lately.
I would think that all the manufacturers (and their highly-paid techs) would have come up with improvements on their own.


Den

.

[palerider]

What is it with all these people wanting to "reinvent" things???
It's been going on for years and another batch of them here lately.
I would think that all the manufacturers (and their highly-paid techs) would have come up with improvements on their own.

the only 're-invent'ing I see is someone who's cut the ciggy plug off their resmed converter (why?) and wanting to hook it direct, instead of plugging it into their battery.

[Omne]

the converter is sized to run a humidifier and heated hose, without those, the load is much lower... it *could* work.

It could, it would depend on how much loss you had in the converter and what the actual output is. Would you want to risk a $150 battery or a $650 machine to find out?...

[palerider]

the converter is sized to run a humidifier and heated hose, without those, the load is much lower... it *could* work.

It could, it would depend on how much loss you had in the converter and what the actual output is. Would you want to risk a $150 battery or a $650 machine to find out?...

there's no "risk" of losing either.

those batteries have been used to power cpaps before. as you'll find if you read some of the threads here. sometime liion packs trip the overcurrent protection on startup, which is more of an issue with the respironics machines, since they start at whatever their set pressure is, while resmeds ramp up over a few second period, meaning they have less of a power surge at startup and are less likely to trip the overcurrent protection.

likewise, there's no reason to believe that a 12-24v input on the resmed converter will damage it, since it's spec'd to handle that.

[Omne]

those batteries have been used to power cpaps before. as you'll find if you read some of the threads here.

Through a converter? We're not talking about using it directly.

[RichInBunlyGoodness]

I have a Resmed S9 I'd like to be able to power with my Qi Battery. Can I splice these together?

try not getting those two unmarked bare wires backwards, that could be bad.

How can I figure out which is which?

[palerider]

those batteries have been used to power cpaps before. as you'll find if you read some of the threads here.

Through a converter? We're not talking about using it directly.

I am quite aware of the current scenario. and again, maintain that the soft start of the resmed makes it more likely to not trip the overcurrent protection.

I've used the converter with a liion battery supplying 12v. it ain't rocket surgery.

[palerider]

I have a Resmed S9 I'd like to be able to power with my Qi Battery. Can I splice these together?

try not getting those two unmarked bare wires backwards, that could be bad.

How can I figure out which is which?

I dunno, why'd you cut the plug off?

[RichInBunlyGoodness]

It seemed like a good idea to my fatigue-addled brain.

It is kind of a long story. Do you really want to hear the whole thing?

[palerider]

It seemed like a good idea to my fatigue-addled brain.

It is kind of a long story. Do you really want to hear the whole thing?

it could be entertaining.... I don't know, offhand, how to tell which wire is positive and which negative, I could look on mine, but there's no positive guarantee that they didn't flip the wire when assembling yours, if, even, indeed, one side or the other is ribbed, or otherwise indicated.