Camping battery for PR System One RemStar Auto

Thanks Texan. I think it would be safe to use the 5A fuse for the PRS1 since the AC/DC transformer only outputs 5A, so it should be reasonable to assume that it would only draw 5A max when on DC.

archangle wrote:

GumbyCT wrote:Note to Self: add spare 5A & 7A fuses to packing list.

The fuses in the Respironics DC cable package are a little strange looking, and they say something to the effect of "only use Respironics fuses." I'm guessing they're slow blow fuses or some such.

Strange looking? I did see the warning mentioned in the manual, but honestly, they look like standard older tube style fuses that were used in cars until around 1980 or so. I have not checked the measurements though. If they are an odd size, I will be very upset with Respironics since they are already screwing me over for the cord. They should at least let me buy standard sized fuses.

Gumby, I tried to source the PRS1 DC connector at Radio Shack and they didn't have it, otherwise I would have build my own as well. However, when I got the cord from Respironics, I noticed it was quite heavy. It is at least as heavy as the AC/DC transformer. I really don't know what's in those cylinders to make them so heavy, nor do I know their function. Without that knowledge, I'm not so certain I should build my own cord.

I really wish I had packed the spare fuses that came with the cord. It would have saved me a miserable night of sleep or lack thereof. I will be sure to pack the fuses in the CPAP case.

Dave.

They were normal 3AG/AGC size glass fuses like cars used to have.

The weird part is a coiled wire for the fuse element. Apparently, it's a "MDL" time delay fuse, which I think is why the coiled wire is used.

The package lists 3A 250V MDL / MDV-T

davelikesbeer wrote: Gumby, I tried to source the PRS1 DC connector at Radio Shack and they didn't have it, otherwise I would have build my own as well. However, when I got the cord from Respironics, I noticed it was quite heavy. It is at least as heavy as the AC/DC transformer. I really don't know what's in those cylinders to make them so heavy, nor do I know their function. Without that knowledge, I'm not so certain I should build my own cord.

Dave.

I got some 274-1573 connectors (Size N- Coaxial DC power plug) at my local Radio Shack. There were in a sliding parts drawer with a bunch of things in plastic bags. It fits snug, but I haven't actually used it yet.

By the way, the precise current at which a fuse blows varies a lot between fuses, room temperature, fuse holder, etc. Different samples of the same machine model may vary a lot, too. Don't be surprised if what works for one person doesn't work for another.

davelikesbeer wrote:Gumby, I tried to source the PRS1 DC connector at Radio Shack and they didn't have it, otherwise I would have build my own as well. However, when I got the cord from Respironics, I noticed it was quite heavy. It is at least as heavy as the AC/DC transformer. I really don't know what's in those cylinders to make them so heavy, nor do I know their function. Without that knowledge, I'm not so certain I should build my own cord.

Unfortunately with the sales staff working many Radio Shack stores today, if it's not a cell phone sale they don't know how to help.

Read this link -
viewtopic.php?f=1&t=64625&p=602960&hili ... ck#p602960
The RS Cable mentioned is heavier than the Respironics factory cable. The ferrite coils are to block harmonics generated by the blower from affecting the DC circuit it is plugged into. Basically so they don't mess up your car when it running which is why they told you now to use it while the car is running.

Mine works fine w/o the ferrite coils but then I am not driving while using it

GumbyCT wrote: Unfortunately with the sales staff working many Radio Shack stores today, if it's not a cell phone sale they don't know how to help.

Read this link -
viewtopic.php?f=1&t=64625&p=602960&hili ... ck#p602960
The RS Cable mentioned is heavier than the Respironics factory cable. The ferrite coils are to block harmonics generated by the blower from affecting the DC circuit it is plugged into. Basically so they don't mess up your car when it running which is why they told you now to use it while the car is running.

Mine works fine w/o the ferrite coils but then I am not driving while using it

Strangely enough, the guy at my Radio Shack was very helpful and knowledgeable. He took the time to find the part, and plug a few sizes of connector in to see if it fit. I know, I was shocked. All for a $3 or $4 sale.

It's going to take a lot of harmonics to damage the gel cell battery you're using, Gumby. Or the charger for it. They could very well be bad for a car, especially the radio. The coils are also to help prevent RF or other noise from getting into the machine and confuse the processor or other circuitry.

There are also concerns in a car about voltage spikes from the starter, alternator noise or other bad stuff coming from the car into the CPAP machine. That's part of the reason they say not to use the cord while the car is running. I sometimes think many of these warnings are just so they can ask "Did you do x? Sorry, but you voided your warranty."

There are also some battery chargers that do some strange things that may cause voltage problems to your CPAP. Some chargers have "desulfator" or other circuits that put voltage pulses and/or 3 MHz voltages on the battery to try to recondition them. I'd be worried about connecting one of these to a battery while it's hooked up to a CPAP machine, even if you're using the Respironics cable with the ferrites.