Micro Pulse Monitor reads red when unhooked

foqus · 11-03-2009, 04:14 PM

Hello folks,

I have been hooked up for 30 days to a shore line, battery switch in
"Use" position, and I noticed a day ago that the BATTERY indicator on the Micro Pulse systems monitor read full. Well, I just disconnected and moved the trailer, ran ONLY a roof fan for about three hours, and I just checked the Micro Pulse and it already reads RED.

Does the Micro Pulse actually show you the battery level (like a stand-alone battery tester would with the batteries unhooked from the Airstream) or does it measure the level of electricity available to the trailer? The Airstream manual does not help at all in this regard.

I don't want to run the batteries down using the roof vent fan, because I don't want to break out the mechanical crank when it's time to move tomorrow.

thanks

foqus · 11-03-2009, 04:16 PM

Follow up: I have a 2006 19' International.

**CanoeStream** · 11-03-2009, 04:31 PM

19' have one or two batteries?

The power reading probably is based on voltage level and how that would indicate charge state -- see voltage drop in storage?. So the monitor doesn't tell you anything about your batteries when you are plugged in and your convertor is kicking out a solid 12+ volts.

Motors tend to use a fair amount of power -- especially the furnace. But 3 hours of intermittent (or was it constant?) Fantastic Fan use? Are your batteries aging? Occasional discharge below 40-45% can impact how much of a charge they can take later. My OEM batteries are finally toast after four full, careful seasons and I'll have to replace them next spring. Hearing about others' experiences, I was ready to credit them with money well spent after they lasted two seasons. It's been a pleasant surprise.

SilverRanger · 11-03-2009, 04:58 PM

I'm on the road, and it's happy hour here in the 2005 Bambi, but it seems like 3 hours is way too short a time on a roof fan.
Try this.

http://service.airstream.com/files/l...a0641f31bf.pdf

foqus · 11-03-2009, 04:42 PM

Clarification:

2 batteries, only 1.5 years old, and maintained well. I just never have had to use battery power (without shore power attached) until today. I have been running only one ceiling vent fan continuously for about three hours. It just doesn't seem like enough power drain to drain to full batteries. Even car headlights can stay on for hours with one wimpy auto battery. So, I am wondering if anyone has an Airstream, running on battery power now, who knows they have good, full batteries, and can go test their Micro Pulse and let me know if it reads in the red.

thanks!!

marco

foqus · 11-03-2009, 04:43 PM

And of course, all the while I was attached to shore power, then battery disconnect was in "use", not "store"....

Wingeezer · 11-03-2009, 05:23 PM

I don't have a lot of faith in that micropulse system I'm afraid!

I think the best way to be sure of your batteries state of charge is to use an accurate digital voltmeter capable of measuring down to at least 0.1 of a volt.

You can find charts on the internet that will relate % charge remaining to voltage measured.

Our trailer has a 12v cigar lighter receptacle in the bedroom. Since we don't use it for anything else, I leave a digital voltmeter plugged into it to monitor the condition of out coach batteries when we are not on 110v.

Brian

**CanoeStream** · 11-03-2009, 05:29 PM

Quote:

Originally Posted by Wingeezer

You can find charts on the internet that will relate % charge remaining to voltage measured.

One such chart is linked in post 3 of this thread.

CrawfordGene · 11-03-2009, 05:43 PM

Even though you've only had your trailer for 1 1/2 years, are they the batteries that were in it when you bought it? If they are, they could have been discharged many times at the dealer and only charged when run way down. That would have shortened their life.

Gene

2airishuman · 11-03-2009, 06:04 PM

Quote:

Originally Posted by foqus

...Does the Micro Pulse actually show you the battery level...

not exactly. but YES depending on WHEN the reading is taken.

it shows the 'surface charge/voltage' not the full equilibrated battery voltage.

so IMMEDIATELY after using a gizmo the micropulse may read LOWER than it will 3-5 hours AFTER using the gizmo.

even without additional charging of the batteries.

the same is true about the micropulse readings RIGHT AFTER charging some...

if only briefly charged (not enough to FILL the batteries) the MP readout may be FULL GREEN.

but wait 2 hours and it can drop back to a lower more accurate measure of the battery state.
________________

i know zip about this 'lectric stuff, but the analogy that works for me is a tub of water exposed to sunlight...

the TOP layer of water may be hot from the sun, but deeper the temp is cooler.

once the water is MIXED and more homogenous, the surface will be more representative of the entire body of water, briefly.

also...

IF the trailer has standard flooded wet cells, TEST each cell for health using an inexpensive hydrometer.

IF u find a dead/weak cell, that will impact the total charge and capacity to hold full voltage.

cheers
2air

OB Bambi · 11-03-2009, 09:08 PM

Ours is a 2006 Bambi SE that I just (about two months ago) replaced the original Interstate batteries. It was doing exactly the same thing. One of the batteries had a cell that kept having the water (acid) level boil down. I replaced both with Kirkland (Costco) batteries and the quick discharge problem went away. I actually thought that the Micro Pulse sensor did tell the charge condition of the batteries during this problem. The only other problem I have ever had with the charging/battery system is it had some problem about 6 months after it was new. At that time I cleaned and retightened the ground wires and the problem went away.

Randy

Barry Parkof · 11-03-2009, 10:34 PM

I have had a similar problem. I bought my 07 new last year on Sept. 29th. I recently noticed that the batterys were not keeping a charge, and a hydrometer check showed that all cells were very low. My digital volt meter also showed that after about 1 hour of not being on the converter the voltage would drop to 8 volts. So I brought the batterys into the local Interstate dealer, and he confirmed they were toast, and said that if I had brought them in within 12 months, they would have replaced them at no charge. I have had the Airstream 13 months. So they prorated them and I am paying about $65.00 per battery. I should have acted on this when I first noticed a problem back in August.
When I bought the trailer, I was concerned that the batterys were sitting for better then a year, but they seemed to perform OK, and a hydrometer check showed the cells to be quite consistent with each other, but only about 60 -75 percent. At the time the dealer would not put new batteries in.