Power Drain

[Newcastle Knight]

I connected the batteries up in the Expanda a couple of weeks ago. It has stood idle for a week or so and I went into the van last night to do some stuff and realised that I had no power.

Checked battery switch it was on, checked batteries with multi meter and needless to say they were very, very discharged.

I did not turn the battery switch off so I am thinking that something has drained the power whilst it was sitting idle. Other then leaving a light on I am not sure what else it could be.

When we did the hand over the Jayco man said that we should leave the switch on the hot water heater, in the outside unit on all the time. I don't recall the logic of this, would this mean that it would drain power even if the system is not being used?

Any ideas on what else it might be?

 

[Burnsy]

G'day NK,

I did that once also, left switch on that is and one day no power. I don't have hot water but my voltage dropped to 9v. My mate recons the setec uses a small amount of power when the battery switch is on, so now I leave it off and no problems since! I guess even small things like sound systems using a small amount of power for memory back up will add to the draw of power if not isolated. It does sound weird about the continuous power supply to the hot water though!

 

[cruza driver]

G'day NK, the HWS switch should be kept in the off position and only needed to be on when hot water is requiered and plugged into 240Volts

When we are on 240 I plug the lead into the van then flick the hws switch on(behind the cover), then when leaving our site I unplug the 240v and turn the switch off. Otherwise when the Expanda is plugged in at home to charge the battery the hws will be continously powered.

As for the battery switch maybe it has been fitted upside down so the battery actually never was getting charged when on 240v. Mine was and the battery would charge up whilst travelling via the anderson plug.

I did a similar thing to you I thought it was charging at home until I realised the switch was upside down The van sat idle in the driveway for a week or 2 unplugged and nothing worked. When you plug the 240 lead in you should here the setec beep also.

 

[Newcastle Knight]

Okay will check that switch however, when I put the batteries in I recall checking the batteries at the terminal and I was getting 13.9volts at the batteries so I assumed that it was working.

 

[cruza driver]

Was that 13.9 via the anderson plug and Prado running or 240V ?


Electric Guru might be able to help you out more than I can but I thought I'd let you know about the switch as I think it was chartrock who's switch was also upside down like mine.

Let us know how you go.

 

[Newcastle Knight]

Through the 12volt but I will check again as part of the process of elimination.

 

[ElectricGuru]

Electric Guru might be able to help you out

Hey NK, I will try to help where I can but as my wife says, I am pretty useless sometimes...

The older SETECs (2006 and prior) did have a 0.25 A/hr power drain that would discharge the battery. From the SETEC User Manual: "Battery Current Drain is always present. The battery should be isolated if the unit is not in regular use. See specifications for details."

For the newer SETECs (ST20-II and ST35-II), the current drain is less than 2 mA so depending on the model you have, there may be something of an answer.

For checking to see if there is something draining it, do you have a good multimeter that has current measurement? You can always remove the SETEC out (with the 240 Vac power disconnected from the van) and go through circuit by circuit and try to find where you are using power. Note that if you are measuring current, remember to change the leads prior to measuring for voltage again. Boots has a great post on how to remove the SETEC - Info-on-installing-battery-16-49-2



For the switches, the switch info should be at the bottom and the wires should be in the top two terminals in general.



Couple of other things, are the batteries brand new? Are you using the SETECs to charge the batteries? Can you supply some details please?

Reason I ask is that the battery may not be getting a full charge. I know the battery I have doesn't charge fully unless it gets at least 14.2 Vdc for at least half a day then drops back to 13.9 Vdc as a maintenance charge. It needs the higher voltage to get the full charge. I dont use my SETEC to properly charge the battery, I have a Projecta 15A smart charger.

Plus the rule of thumb is to have at least 10% of the battery capacity available from your charger, ie 100 Ahr need at least a 10 A charger to ensure the battery is fully charged.

Also if the batteries are a bit older, then they may not be abe to hold a charge as well as a brand new one.

Sounds like a dilly of a pickle, keep us posted on progress...

Cheers!

 

[Newcastle Knight]

The batteries are not brand new, but have been performing well. Both batteries were charged using my ctek charger prior to being installed.

I disconnected the power yesterday and both batteries were showing 12.8 volts, so Iam fairly on confident the stec is charging them. I turned off the battery switch and checked this afternoon and batteries are showing 12.8 volts.

I have a feeling that I may have left the water pump on but will keep checking over the next few days.

 

[Newcastle Knight]

Think I have worked out the culprit of the power drain. Checked batteries again today, still at 12.8v. Had a thought and then realized that with the battery switch on the stereo was on and there in lies the voltage thief. Thanks for everyone's input.

 

[Burnsy]

Hi NK, that's what was happening to me too. I fitted my stereo myself and don't have a isolation switch for that yet. Does Jayco not fit one?

Cheers mate!

 

[Newcastle Knight]

Hi NK, that's what was happening to me too. I fitted my stereo myself and don't have a isolation switch for that yet. Does Jayco not fit one?

Cheers mate!

Not that they told me about....lol

 

[ElectricGuru]

Hi NK, that's what was happening to me too. I fitted my stereo myself and don't have a isolation switch for that yet.

Hey NK, glad you got the perpetrator. Must be one heck of a stereo with that kinda drain on the battery's. :music: lol

Is there any way you could measure the standby current using a multi meter as discussed and post what the power drain actually was. Would be good so people know what kinda power that thing uses while on standby. I will measure mine when I get a chance this weekend and we can compare info...

I am thinking I am going to fit a switch on the stereo as well after reading this post.

Well done!

Cheers guys!

 

[Newcastle Knight]

Will see what I can do over the weekend. The stereo was on for over a week and it has this light show on the display so I gather running 24hrs a day for probably eight days would have drained i.

 

[cruza driver]

Good to see you have found the problem NK

 

[Moto Moto]

Nice work guys, another thing to keep in mind. Love this forum!

 

[ElectricGuru]

Hey All

Ok, got to checking it over the weekend and found when the radio was left on after the power was cycled, then there was a power drain of almost half an amp...



However, when I turned the radio off, the current dropped down to 0.01 A so not really a significant amount. Mind you, I am still going to install a battery switch...

I have the older SETEC so the current drain is always present...

Cheers.