Equus Battery Monitor - Fiberglass RV

Thread Tools Search this Thread Display Modes
Old 08-11-2010, 08:06 PM   #1
Senior Member
Name: Paul
Trailer: Escape 19 ft (sold) Escape 21 May 2014
Posts: 258
Equus Battery Monitor

Eric T recently posted a message on another forum containing a link to a battery monitor that plugs into a 12 volt outlet and gives measurements of what charge is left in your battery. I found the unit is only available from Amazon, and will run about $18 US with shipping. Here is the link and description:

http://www.amazon.com/Equus-3721-Battery-Charging-Monitor/dp/B000EVWDU0/ref=sr_1_1?ie=UTF8&s=automotive&qid=1280538628&sr= 8-1-spell

I took some time on a recent week long trip to compare the Equus battery monitor that Eric recommended with hydrometer readings. Supposedly hydrometer readings are the most accurate method of measurement short of having expensive test equipment.

I would have to say that hydrometer readings are difficult, touchy and the instruments suffer from poor quality. It took me two purchases to find a working model and the second model is going back as it has filled itself with battery acid and it cannot be easily drained. It is also made of glass. The inexpensive hydrometers give readings on a scale with tick marks between numbers, the glass insert must be balanced so it is floating in the acid you have drawn from the battery. In addition, you must add or subtract depending on what the thermometer tells you. In all, I felt a cumbersome process that is easily skewed. There may be better models available but after visiting four stores I felt I selected the best available, it was less than $6.

Below is a table of what I found with readings from the Equus battery monitor and a hydrometer test. As you can see there is a pretty good correlation of results. I really distrust the hydrometer readings because there is so much chance for error and obtaining a precise reading.

In conclusion, if you boondock, have a 12 volt outlet and want to monitor your battery this definitely beats running hydrometer tests on your battery. You have a precise number and can even tell what power a particular device is drawing by running it and seeing the monitor change. I recommend a hydrometer for occasional (seasonal) testing on all the cells on your battery but if you want to to easily watch your battery the Equus batttery monitor does the trick.
Attached Images
File Type: bmp battery table.bmp (206.1 KB, 33 views)
Paul Braun is offline   Reply With Quote


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Charger, battery monitor, float charge level Ami P Problem Solving | Owners Helping Owners 4 07-10-2009 06:12 AM
simple battery monitor Scott S. Problem Solving | Owners Helping Owners 6 10-02-2008 05:38 AM
Using Xantrex Battery Monitor kevin61 Problem Solving | Owners Helping Owners 0 07-13-2008 02:42 PM
Dirt Cheap Battery Monitor AZCharlie Care and Feeding of Molded Fiberglass Trailers 2 03-24-2007 11:52 PM
Battery Monitor Toodie Care and Feeding of Molded Fiberglass Trailers 17 08-02-2006 04:06 PM

» Upcoming Events
No events scheduled in
the next 465 days.
» Featured Campgrounds

Reviews provided by

All times are GMT -6. The time now is 11:05 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.