Teamed S9 12v power issues

Hello everyone
Firstly thanks for the opportunity to join. And now the problem, I am a long distance truck driver in Australia and I am having problems with my machine on 12v power. I have the converter supplied that covers the 12v/24v power and the machine runs fine on 24v power as well as at home on mains supply. Has anyone had similar problems. I have had a power supply in the truck added straight from the batteries that is 12.5v at the plug socket. New batteries were installed I could really use some help on this. I have set the machine to manual for the humidifier and lowered the settings. Please help as Sleeprite Australia and my local sleep guru are lost.

Mattmac wrote: ↑

Fri Jun 07, 2019 10:36 pm

Hello everyone
Firstly thanks for the opportunity to join. And now the problem, I am a long distance truck driver in Australia and I am having problems with my machine on 12v power. I have the converter supplied that covers the 12v/24v power and the machine runs fine on 24v power as well as at home on mains supply. Has anyone had similar problems. I have had a power supply in the truck added straight from the batteries that is 12.5v at the plug socket. New batteries were installed I could really use some help on this. I have set the machine to manual for the humidifier and lowered the settings. Please help as Sleeprite Australia and my local sleep guru are lost.

Welcome to the group!

So exactly what problems are you having? Does is fail to come on? Does it come on and shut down when the pump starts? Does it blow the fuse? (Hopefully a fuse was included when they added the socket.) You might try turning off the humidifier and heated hose completely. If they used thin wire, like 22 gauge, its possible that the voltage drop brings it down below the under-voltage cutoff for the pump. Al sorts of possibilities - more info is needed!

Mattmac wrote: ↑

Fri Jun 07, 2019 10:36 pm

Hello everyone
Firstly thanks for the opportunity to join. And now the problem, I am a long distance truck driver in Australia and I am having problems with my machine on 12v power. I have the converter supplied that covers the 12v/24v power and the machine runs fine on 24v power as well as at home on mains supply. Has anyone had similar problems. I have had a power supply in the truck added straight from the batteries that is 12.5v at the plug socket. New batteries were installed I could really use some help on this. I have set the machine to manual for the humidifier and lowered the settings. Please help as Sleeprite Australia and my local sleep guru are lost.

Normally lead acid batteries put out more than 12v closer to 13v maybe the Resmed power pack is thinking your battery is deprecated and is shutting down due to under voltage protection.

Jas_williams wrote: ↑

Sat Jun 08, 2019 7:48 am

Normally lead acid batteries put out more than 12v closer to 13v maybe the Resmed power pack is thinking your battery is deprecated and is shutting down due to under voltage protection.

A fully charged lead acid battery is 12.6 to 12.7 volts. It will drop from that as it is used, so anything that runs from a "cigarette socket" should be expecting a voltage down to at least as low as 12.0, and should go to 11.5. My large battery bank frequently goes below 12 when the fridge is running and nothing I run (including a cpap) minds that. I forget the exact rating of the ResMed 12/24 converter, but I thought it went fairly low, to least 11.5.

This does bring up another point: If this is connected to the starting battery, the load of a humidifier/heated hose could easily drain the battery to the point where it can't start the engine in the morning. The pump itself should be OK, but the best practice is to add a second, deep cycle battery that is connected while driving, and disconnected at night to preserve the starting battery.