Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account


New Posts   Today's Posts

HDM Z-1 power consumption?
#1
Does anyone know if HDM has a table like Resmed's that shows the power consumption of their units (in amps) at given pressures?

That would be VERY helpful in sizing a battery for more extended emergency usage.

OMM
Post Reply Post Reply
#2
(02-01-2015, 09:32 AM)OMyMyOHellYes Wrote: Does anyone know if HDM has a table like Resmed's that shows the power consumption of their units (in amps) at given pressures?

Um, not to be picky, but power is not measured in Amperes, it is measured in Watts. Watts equals Volts time Amps. So if you know two out of three you can figure out the third.

Ed Seedhouse
VA7SDH

The above is my opinion.  It is just possible that I may, occasionally, be mistaken.

I am neither a Doctor, nor any other kind of medical professional.

Everything put together sooner or later falls apart.
Post Reply Post Reply
#3
(02-01-2015, 01:51 PM)eseedhouse Wrote:
(02-01-2015, 09:32 AM)OMyMyOHellYes Wrote: Does anyone know if HDM has a table like Resmed's that shows the power consumption of their units (in amps) at given pressures?
Um, not to be picky, but power is not measured in Amperes, it is measured in Watts. Watts equals Volts time Amps. So if you know two out of three you can figure out the third.


Um, yeah, for these purposes, it is.

electric current: a movement or flow of electrically charged particles, typically measured in amperes.

Given the voltage, 11.7-14.4v for a 12 V storage battery, capacity is shown usually as amp hours.

That's why Resmed Technical Services, when they wrote their battery guide, used current draw in amps for all measurements.

We are looking for the same data for the Z-1.

OMM
Post Reply Post Reply


#4
Cannot find power consumption V pressure data for the Z1.

The Z1 uses a 45 Watt-hour, 14.4 Volt Li-ION battery. They say one can get 8 hours use from that battery at 14 cm-H2O pressure.
Li-ION chemistry batteries have a fairly constant Voltage during discharge.
At 14.4 Volts, we can convert W-Hr to Amp-Hr.
The battery would be a 3.125 Amp-Hr battery.
For an 8 hour run time, one can infer the running current is 3.125 Amp-Hr/8 Hr = 390 milliAmpere current draw.
(Wow, that's seems incredibly low!)
INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.
Post Reply Post Reply
#5
(02-01-2015, 02:07 PM)OMyMyOHellYes Wrote:
(02-01-2015, 01:51 PM)eseedhouse Wrote: Um, not to be picky, but power is not measured in Amperes, it is measured in Watts. Watts equals Volts time Amps. So if you know two out of three you can figure out the third.


Um, yeah, for these purposes, it is.

Um, no. It's a matter of definition. Power is measure in Watts by definition.

Quote:electric current: a movement or flow of electrically charged particles, typically measured in amperes.

Yes, but current isn't power.

Quote:Given the voltage, 11.7-14.4v for a 12 V storage battery, capacity is shown usually as amp hours.

Sure, but that's not power, that's capacity. Say you have 2000 amp hours at 12 volts. If your rig consumes 90 watts (the rating on the power supply for mine) it will draw (at full power) 90/12 = 7.5 amps and it will take 2000/7.5 = 26+ hours supply those 2000 amp hours.

These are only approximations, of course. Batteries aren't perfect.

Quote:That's why Resmed Technical Services, when they wrote their battery guide, used current draw in amps for all measurements.

We are looking for the same data for the Z-1.


If you know the power rating of the machine you can compute this easily. If your power supply is rated at 120 watts then the current draw is 120/12=10 amps. So to run for 24 hours you'll need a battery that can supply more than 2400 amp hours. Straightforward arithmetic.

If you don't know either the power consumption or the current draw you need to find out at least one since you can probably assume a 12 volt power supply.



Ed Seedhouse
VA7SDH

The above is my opinion.  It is just possible that I may, occasionally, be mistaken.

I am neither a Doctor, nor any other kind of medical professional.

Everything put together sooner or later falls apart.
Post Reply Post Reply
#6
VA7SDH
There is an Amateur Radio Thread in Off-Topic.
http://www.apneaboard.com/forums/Thread-...-operators
INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.
Post Reply Post Reply


#7
(02-02-2015, 03:12 PM)eseedhouse Wrote: If you know the power rating of the machine you can compute this easily. If your power supply is rated at 120 watts then the current draw is 120/12=10 amps. So to run for 24 hours you'll need a battery that can supply more than 2400 amp hours. Straightforward arithmetic.


ROFLMHO

Oh, that too funny!

OMM
Post Reply Post Reply
#8
(02-01-2015, 09:32 AM)OMyMyOHellYes Wrote: Does anyone know if HDM has a table like Resmed's that shows the power consumption of their units (in amps) at given pressures?

That would be VERY helpful in sizing a battery for more extended emergency usage.

OMM

NO... the HDM does not have a milli amp hour for various pressure ratings chart like ResMed did for the S-9.

On portable pap like the Transcend and Z-1 the manufacturers are pretty good about getting you information on draw and recharge data. Transcend has a solar charging panel as an option.

My experience with Transcend is that at 16 pressure the normal 8 hr battery doesn't cut it. I use the larger 16 hr batter for consistent 8 hours per charge.

In doing any battery supply power option for pap I always like to engineer in extra capacity. I hate waking up when the battery goes dead.

This also assumes any battery pap option you go into it understanding heated humidification on battery is not a realistic option. You need to plan on either pass over humidification or using nasal irrigation.

Hope this helps.
(Just a truck driver with sleep apnea )
Post Reply Post Reply
#9
I think the standard most knowledgeable members use is a requirement of 150%. Especially since there are probably dozens of variables that go into the equation. IIRC, the ResMed tables used that %'age too.

BTW, this afternoon, I did a quick, informal test on the Respironics 560 w/o humidification. Ran about .32 AH current draw off of an old, but recently charged, 10 AH 12v battery. So I would plan on .5 AH draw. So, for the avg 6 hours a night, I should get a 2-3 nights off that machine with that battery. Granted, most of that nap time was probably nearer the low end of my pressure envelope, so it is probably optimistic and closer to 2 nights max ...

Am eager to see what the Z-1 will do. I would like to be able to get at least that good out of it - that way I would feel good that a 5 AH 12V would get me through a transoceanic flight in either direction absent a power source ont he plane. I am also trying to get a 5 A battery shoehorned into the little case I got for the Z-1
Post Reply Post Reply




Possibly Related Threads...
Thread Author Replies Views Last Post
  [Equipment] res med aircurve 10 & battery power, DC adapter miami bob 8 428 02-09-2017, 06:55 PM
Last Post: OMyMyOHellYes
  Devilbiss DV5x power chart: pressure/DC Amps/Amp-Hours Night Train 1 168 01-23-2017, 04:15 PM
Last Post: OMyMyOHellYes
Question [CPAP] Off-grid power supply for camping/hiking? LokoLobo 2 466 12-21-2016, 09:29 PM
Last Post: trish6hundred
  [CPAP] Power supply resmed s10 plschwartz 5 478 12-16-2016, 06:55 PM
Last Post: OMyMyOHellYes
  Insurance won't pay for power cord? CharlotteYork 13 1,212 11-17-2016, 11:58 PM
Last Post: tzk321
Idea ResMed S8 repair for no power SuperSleeper 4 643 11-17-2016, 02:41 PM
Last Post: 10bigal10
  Power Outage: Stay Awake Or Sleep W/O CPAP? player 11 1,014 10-26-2016, 08:29 PM
Last Post: sonicboom

Forum Jump:

New Posts   Today's Posts




About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.

For any more information, please use our contact form.