Power Inverters

[Steve L]

I am an adult sleep apnea sufferer and have to use a CPAP or constant pressure air pump, at night to sleep safely. I am having to change to an automatic pump which does not have 12 volt back up facilities.

I need a contingency plan for power failure.

I've thought of using a power inverter to power the pump should we loose mains electric on site. But what I really need to know is how big does the inverter have to be? My current pump according to the data on the base of it requires 1 amp at 240 volts ac, and 3 amps at 12 volts dc, to run it.

So assuming I need 8 hours of the pump running, can any of you electronics buffs recomend an inverter and also where I could obtain one.

Many thanks in advance for your advice.

Steve L.

 

[Legsmaniac_374344731]

I'm a tad confused.

You say "I am having to change to an automatic pump which does not have 12 volt back up facilities."

Then you say "... and 3 amps at 12 volts dc, to run it." If the current pump allows 12V, why change?

What you need is a UPS and I happen to have two, brand new, unused still in their boxes. I'm happy to sell one to you for

 

[Steve L]

Hi Legs.

The reason I have to change is based on medical grounds. It seems that my breathing rate slows considerably occassionally and it is beyond the current pump's capacity to cope. The automatic pump senses and adjusts accordingly and also records the incidents more accurately so the medics can understand my condition better.

Unfortunately the auto pump does not come equiped for any alternative to mains 240 volt power. I will have to speak to the hospital clinition this week and ensure they are happy with my proposal. You know how funny they get if you don't agree with them. (power and al that jazz)

I'll keep you posted onwhat they say.

Many thanks. Steve.

 

[ProfJohnL]

Hello Steve,

I am sorry to read of your apnea.

One thing that always amazes me is the cost of medical equipment, especially the pieces that are designed for life support, and I think that your respiration aid would fall into that category.

On of the reasons for the cost of these devices is the attention to to detail, and reliability that they must have especially when you consider the consequence if they fail. For that reason, I am absolutely certain that no supplier would knowingly sell or supply a normal consumer based power inverter or UPS for a life support function.

I think you should consult your equipment supplier, who will be able to tell you if there is a suitably approved emergency standby power supply for use with your apparatus.

 

[RogerL]

Steve - if it uses 3amps at 12v, that's 36w, in which case it'll run off a relatively low powered inverter - assuming the replacement is the same.

If you connect the inverter to the battery and always run from the inverter that will do the same job as a UPS - mains will charge the battery when available and the inverter will gradually run down the battery in the event of a power cut. 8 hours at 3 amps is 32 amphours, allowing for inverter inefficiency.

You do need to get an exact power requirement from the new equipment's supplier.

 

[Barking]

Hi Steve

I do not have the new gucci version as you but have happily ran my CPAP using a 150w inverter, when not on mains, for the last 5 years. Not had a problem to date!

Barking

 

[Steve L]

Thanks for the info Barking.

I've got a right "Jobs worth" clinitian here at Hereford who I think worked for the "secret army" in her last job, as trying to get anything out of her is harder than "bleeding a stone".

It took a letter to the consultant to get the Automatic pump on the NHS. She wanted me to shell out my own hard earned for one from her supplier.

My old pump has a 12 volt facility, but the new one doesn't which I found a bit silly as I always thought technology went forward, not reverse.

I've got to see the bat soon, so I'll have to ask her royal permission before I use alternative power soarses.

Cheers.

Steve L.