| Author | Message | ||
| OAE Palmer (66.166.141.53) Rating: |
Hey Folks...! Long time no posts from me.... I have shut down my internet service and have been doin fine w/o it...got lots of time back for the effort! The reason I made an effort to post here today is that I seem to have stumbled onto a "secret" that MIGHT help many of you in securing "house batteries". It seems as tho EVERY cell-phone routing station (how many zillions of those are there in the USA?) has to have a back-up power system... typically a genset AND a bank of batteries. The batteries are swapped out on either a time schedule or based on the "charge float rate". I stumbled onto a company that uses the time in service sched. What I purchased from them was 900 amp hr. 12 volt gellcells. They are about the size of a std. automobile battery but weight more due to denser packed plates I would suppose. The batteries I bought were rated at 13.5 - 13.8 volts nominal float charge....and when tested by me before purchase, they all tested 13.2 volts or higher 8 hrs after charging on a 2amp charger for a couple of hours. I picked up 12 of these little babies for a whopping $60.00. I know they are not the most perfect product for my purpose..but at the price I expect to get a year of service from them.. I say contact your local cell phone maintaince mgr. and see if you can wrangle a deal...the price is hard to beat eh? | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
Wow...what a deal. Makes me want to rethink the Trojan T-105's I right now have decided to use on my coach. You got a good deal. You batts will be very easy to capacity check for proper capacity. Just grab a hunk of the proper sized wire the correct length for about a 8 hour discharge rate down to about the recommended mimimum... Then charge up the cells, let them sit for about 3 days to remove any surface charge, then take a starting voltage level, then direct connect (short) pos to neg... ... each battery with the hunk of wire sized and lenghed for a 8 hour discharge rate. The wire should get warm, BUT NOT HOT. Take a voltage reading every hour... ...for 8 hours. Then figure out the amp hours taken from each batt. Then you can total the actual capacity of each of your bargin cells to see if they are up to spec. This is what we did with our old recycled Ni Cads years ago. Easy and actually fun to do with a hot tottie in the winter, or a cold six pack in the summer. I bet that if the string of batts is properly sized for your coach application that they will last a number of years. The secret is a proper discharge-charge cycle. Go for it!! | ||
| Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A |
I work in the cellular industry (for a carrier) and I would be a little worried about the batteries obtained that way. The problem is that batteries - particularly the sealed gell cell, or what is known as a valve regulated wet cell (looks the same, but internally is different) - are usually not well maintained. Since the disappearance of the old style tank type batteries, the whole skill of battery nmaintenance and charging has gone away from cellular companies. You used to be able to take a reading via a hydrometer and know what the battery was up to, but no more. In addition, the battery work is now contracted out to a battery company for periodic load testing and renewal (replacement) when found to be failing. They need to squeze every penny out of them in those cases because the value evaluation of the contract is based on the performance of the batteries. It used to be that cellular companies could throw mioney at a problem and get it back in billed minutes of use. Now, the margin of a cell phone company is very slim (by comparison). With 5 or more competators in teh field, vs the 2 we used to have, carriers have to watch where the money goes. You could, possibly, be seeing batteries that did not meet spec and may have some substantial life left in them, but I have a hunch you will have a considerably shortened longivity of those batteries. On the other hand, if you don't mind fussing with them, it could save some real bucks - you just trade work for dollars. Anyway - good luck and I hope it works out for you. Doug St Louis MC9 | ||
| OAE Palmer (66.166.141.53) Rating: N/A |
Thanks for your collective perspectives they re-enforce my thoughts on this "juice on the cheap" deal. I have have reaped a great many bargains on my local boneyard/recycler, this one was among the best. My logic was.... for $60.00 if I only got 60 days of actual use from them it would be a break-even deal...it got me down the road & my expectations are not elevated. The day will arrive soon when I have to bend over and cough for the lead-acid monster....but like all the betterdays to come...thats down the road, in the meantime "I be smiling" I will try to find time this w/e to run "the test" & will post the results. Knowing what guage and length of wire needed would be a great help....Henry? | ||
| Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A |
Hey guys how do you find out who's doing the sevice in your area? I like the idea but can't find who's doing the sevice around here | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
I knew you would ask about the wire diameter and length. Now what do I do? The ni-cads we capacity tested years ago were only 1.5 volts each. You have to have a string of 10 cells total to get the nominal 12 VDC. According to Ohms law, this related to a lenth of 18 gage wire about 27 feet 9 inches long... ...to capacity test one cell at a time. Remember, the ni-cads were only 1.5 volts each. NOT 12 volts each. The Ni-cads were rated at 120 amp hours each, but could safely be totally discharged. In fact, they liked it. We divided by 8 hours the 120 amp hour capacity, giving us about a 15 amp discharge per hour at a nominal 1.5 volts This is important. You batts are 12 VDC, NOT 1.5 VDC. I do not know what size or length wire you would need. Sosss...another way to capacity test your gel cells would be just divide your WORKING discharge rate in hours... ...by the amount of discharge you desire...says 50%, then get a 12 VDC light bulb and hook it up to each battery. Then take hourly voltage readings to see how the battery stands up to being discharged. This is easy... ...because the bulb will visably darken if things are wrong and the battery weak or bad and the voltage crashes. Soooos...you need to determine two things...the actual capacity of the gel cells in service AND a bottom voltage rating you do not wish to drop below. If you have 80 amp hour rated 12 VDC cells, and you want to only run them down to a 50% discharge rate... ...for long service life AND you want a bottom voltage not to drop BELOW 12.0 volts each, that means you... ...have 40 amp hours times 12 volts OR...about 480 watts to discharge from each cell over an 8 hour rate. Divide this by 8 hours and it means you need about a 40 watt 12 volt light bulb to conduct your capacity test with. Grab some heavy 12 gage wire and hook up the light bulb. Then take hourly voltage readings over 8 hours to get a capacity total. You can read a book using the light generated while you conduct the capacity test.  Good luck. | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
Er....ah....I meant a 60 watt bulb. Sorry. I HATE getting middle aged. Henry | ||
| OAE Palmer (66.166.141.53) Rating: N/A |
Thanks HRB... I'll give it a try in a couple of days...got the bulb and the wire...just need the time. I'll be gettin' back with the results ...... |
