| Author | Message | ||
| Roger Baughman (Roger)
Registered Member Username: Roger Post Number: 51 Registered: 11-2006 Posted From: 69.232.64.77  Rating: N/A |
I would like to know what an equalizer is and what it does. Also what are the good and bad of using one. All I think I know is that it has somthing to do with the batteries. Thanks to all. Roger | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 389 Registered: 3-2007 Posted From: 71.55.230.210  Rating: N/A |
Roger; an equalizer takes 24 volt dc and converts it to 12 volts. it is installed on a 24 volt system and then allows you to have 12 volts to use for other equipment,radios, refers,and whatever you have that need 12 volts to operate it. They are different units as for as amp draw so what you need would have to calculated. They usually have one on E bay or another nut may have an extra for sale. Gomer | ||
| Nellie Wilson (Vivianellie)
Registered Member Username: Vivianellie Post Number: 155 Registered: 11-2008 Posted From: 76.64.243.25  Rating: N/A |
Hi Roger - This from the dumbest of the lot, so take it with several grains of salt. Having just had my Vanner Equalizer disconnected, I got a crash course (rudimentary, I'm sure) on how they work, what they're supposed to do, etc. The bottom line, as I understand it: They're of little value unless you're running a 12V supply off your 24V system. I am not, though it looks like the PO was: TVs and radios and such. The theory being (and it must work, considering the rave reviews on this board) that the equalizer keeps the two twelve volt batteries (well, duh) equalized. It keeps the charge of the 12V source battery from falling below the charge of the non-tapped battery - which would result in one battery (the source) being constantly undercharged and the other boiling. It's important (as i understand it) that the 12V source battery be the 'A' battery - the one grounded to the chassis. Mine was hooked up in reverse so - even if I wanted 12V power - it wouldn't have worked. I mean, I'd get the power but the batteries wouldn't have equalized. If you're not tapping 12V, the Equalizer does mothing the batteries (hooked in series) don't accomplish by themselves. Batteries in series equalize one another without any external mechanism. So (I'm surmising here) it seems either an equalizer OR a converter would accomlish the same thing (24V > 12V). But like I said, FWIW! Nellie Wilson PS. I'm now donning my helmet and Kevlar vest in anticipation of the flack to follow. | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 390 Registered: 3-2007 Posted From: 71.55.230.210 Rating: N/A |
golly nellie u b gettin too smart LOL. u hit the nail just right and didn't get your finger hurt haha. gomer | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 749 Registered: 7-2006 Posted From: 68.18.13.68  Rating: N/A |
An equalizer will provide you with 12vdc from two 12vdc batteries that are connected in series (with one another) for their use in a 24vdc system. It's not the best way to get 12vdc from 24vdc. It's a step above a simple center tap between the two 12vdc bats. The equalizers are noted for their failure rate; most commercial bus operators remove 'em, and toss 'em. A 24vdc to 12vdc converter, on the udder hand, will provide you with 12vdc from any 24 vdc source, and it matters little if it's from two 12vdc batteries in series, a 24vdc battery, four 6vdc batteries, a 24vdc generator, or 24vdc alternator. BIG difference! | ||
| Keith Wood (Ft6)
Registered Member Username: Ft6 Post Number: 75 Registered: 8-2008 Posted From: 70.212.167.34 Rating: N/A |
"Got a problem? Odds against you?" Oh, not THAT kind of Equalizer? | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 750 Registered: 7-2006 Posted From: 68.18.13.68 Rating: N/A |
That's my "Uncle Louie", Keith! "Perhaps I should explain to you, exactly what I do" (Joe Pesci; Casino) | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1252 Registered: 5-2001 Posted From: 65.74.69.188 Rating: N/A |
John, the stuff that I have seen posted in the past gave me the idea that the equalizer did it's job by regulating the 12 volt output to exactly half of the 24 volt input. This was to let the regulator of the 24 volt system provide the same PER CELL voltage for the 12 volt system. A converter, on the other hand, puts out a regulated voltage that is fixed, if I undertood right, which does not adjust for changing recharge needs. Did I get this wrong? Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1468 Registered: 12-2000 Posted From: 76.68.120.70  Rating: N/A |
Most commercial operators are tossing their equalizers?? And substituting what in it's place? The 12 volt part of the bus system is designed around the equalizer being there. Otherwise what happens to the battery set? Newer buses are using a lot of 12 volt power, with 24 volt alternators charging the show. Somebody welding on those buses without following the directions for unhook and hook up? happy coaching! buswarrior | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 751 Registered: 7-2006 Posted From: 74.230.99.203 Rating: N/A |
Tom Apples and tomatoes, Tom. The equalizer if fine, as long as both batteries are fine. One dead cell in one battery will change the scope of things considerably. You can't "balance" what refuses to be balanced, and the good battery will be providing the entire 12 volt load before too long. And of course, a faulty equalizer will kill a battery quickly. A converter will run off the alternator to provide 12v, regardless of battery condition, or off the battery bank as needed. If it goes faulty, no battery will pay the price. BW If I remember right, MCI used the "center tap" approach for years. I have the MCI manual's schematic for that. No MCI manual I have seen to date, recommends the use of an equalizer. Hell, I've been wrong before, and I'll be wrong again, but I'd have to see the proof regarding this one before I'll take a bite of crow. | ||
| Edward J. Sommers (Sommersed)
Registered Member Username: Sommersed Post Number: 39 Registered: 10-2004 Posted From: 148.78.155.174 Rating: N/A |
I carried a Vanner Equalizer in the hold for years but had no real use for it till recently. This last summer during the high fuel prices I started staying in one place for longer periods of time, boondocking (I despise RV Parks), and needed to keep my start batts up. Normally I did this using two 12 volt, 10 anp chargers but one went down so I decided to play with the Vanner. After hooking it up according to the diagram on the unit, I was VERY pleased with the results. The Vanner kept the voltage between the batts at one half volt while charging just one batt. Just for kicks, I placed a 12 volt load on the 24 volt start batts, and recharged during the day, and they stayed right there, where it's supposed to! I was so impressed that I am now in the process of switching over to a 24 volt house system. My solar panels are wired in 24 volt configuration, charging 24 volt batt bank of 8 6 volt batts, but being tapped for 12 volt lighting/entertainment system (ect), and being equalized with the Vanner. My solar charge controller will be programed to divert a small 24 volt charge to the start batts automatically once a week. Efficient automation is GREAT! Ed | ||
| Roger Baughman (Roger)
Registered Member Username: Roger Post Number: 52 Registered: 11-2006 Posted From: 75.3.204.122 Rating: N/A |
Hanks Nellie, You sound pretty smart to me. No need for the helmet or the Kevlar from me. And thanks to the rest of you too for the feed back, it is much appreciated, Roger | ||
| Chuck Newman (Chuck_newman)
Registered Member Username: Chuck_newman Post Number: 284 Registered: 1-2005 Posted From: 76.246.254.144 Rating: N/A |
An equalizer configuration will always draw (load)12vdc current from one battery, or one-half of a 24vdc bank. As John states, a converter will "convert" 24vdc to 12vdc. I'm going to try to upload a pdf file that shows both configurations clearly. Haven't uploaded a file to this board before so bear with me. Whether the upload works or not the main difference is with an equalizer you are always drawing 12vdc current from one battery as shown. With a converter you are drawing 12vdc current from both batteries. A more efficient design with greater capacity. Another simple way to think of the two devices is: An equalizer works only when the batteries are charging. A converter works only while the batteries are discharging. And some converters have regulated output. Some do not. The one shown supplies one-half of the existing bus voltage ie: 22.5vdc batteries would get 11.25vdc at the converter output. One other thing for clarification, the Vanner equalizers (at least the previous generation) can on "equalize". The Sure Power model shown can function as an equalizer or a converter as shown. | ||
| Chuck Newman (Chuck_newman)
Registered Member Username: Chuck_newman Post Number: 285 Registered: 1-2005 Posted From: 76.246.254.144 Rating: N/A |
It didn't work. I asked the Boss Nut for help. | ||
| Nellie Wilson (Vivianellie)
Registered Member Username: Vivianellie Post Number: 160 Registered: 11-2008 Posted From: 74.13.197.93 Rating: N/A |
Chuck - You say: "An equalizer works only when the batteries are charging. A converter works only while the batteries are discharging." Can you elaborate (my ladylike way of saying Huh?) Nellie Wilson | ||
| Chuck Newman (Chuck_newman)
Registered Member Username: Chuck_newman Post Number: 286 Registered: 1-2005 Posted From: 76.246.254.144 Rating: N/A |
Nellie, an equalizer and converter both physically look alike and are electrically related to each other only in the fact both work in battery circuits. Other than that they are two separate devices doing different jobs. Since I can't get my diagram up for now, imagine two 12vdc batteries connected in series to give a total of 24vdc. Most 24vdc equipment (buses, tractors, graders, etc.) that need to power a 12vdc device (radio, headlamp, etc.) get that 12vdc by connecting + and ground lead from the device directly to one battery. Hence one battery is discharging 12vdc current while the other is not discharging at all, assuming no other loads, and no charging current present. Now we start the engine and the alternator is charging both batteries equally at 24vdc. Both batteries have equal charge current from the alternator, but unequal discharge current due to the extra 12 volt load (light, radio,etc.) on one of the batteries. If left that way, that battery will never receive the same charge as the other. The function of the equalizer is to equalize or balance the "charging current" into each battery to compensate for the increased "output current" on one battery. The battery with the 12 volt tap will get more charging current than the other, simply because it has a greater load current than the other. So an equalizer works only when the batteries are being charged. When the alternator is stopped, it has no function since the 12vdc tapped battery still is discharging to the 12vdc loads with the engine off (interior lights, fans, TV, etc.) A converter would connect across both batteries in the above simple diagram of two batteries connected in series to give 24vdc. In other words, no tapping of a single battery. The converter internally converts the input voltage to 1/2 that value at the output. So a system battery voltage of exactly 24vdc would give a converter output of 12vdc for lights, fans, TV, etc. This happens when the batteries are charging, OR not charging. In other words, the converter is working regardless of whether the alternator is charging the batteries or not. The important point here is both batteries will have equal charge current and equal discharge current because their is no battery tapping between the +24 and ground posts. My statement that converter works only while the batteries are discharging was a simplification to keep the focus on current OUT of the batteries to 12vdc loads, whereas the equalizer works on the current INTO both batteries during the charge cycle. Two things to keep in mind: 1. A "converter" in RV terms converts 120vac to 12vdc. Not a valid term for what it does. In fact a typical RV converter is just a "power supply" or "battery charger", depending on your preference of terms. The "converters" described here are specialized devices not found in RV parts stores and catalogs. 2. The converter described can have either an "input/2" configuration or a regulated output, but not both in the same model. I use a 100A Sure Power for lights, fans, DC outlets, etc. because they don't need tight regulation. If my house batteies are at 21.7 volts, the converter output is 10.85vdc. Yes, it's time to recharge at that level, but exhaust fans and lights still will work at that voltage. I use regulated output converters for all electronic devices and appliance circuit boards. This gives me precise 12vdc to those devices with a house bank input anywhere between 17vdc and 33vdc input. Hope this helps. | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 752 Registered: 7-2006 Posted From: 72.146.76.92 Rating: N/A |
No need to "hope", Chuck. Well explained! | ||
| Edward J. Sommers (Sommersed)
Registered Member Username: Sommersed Post Number: 40 Registered: 10-2004 Posted From: 148.78.155.174 Rating: N/A |
"An equalizer works only when the batteries are charging." Sorry, but NOPE.. An equalizer (at least the Vanner) works anytime there is a difference between the high and low sides! Ed | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 753 Registered: 7-2006 Posted From: 72.146.76.92 Rating: N/A |
Ed - To substantiate Chuck's comment, the dialog from Vanner is as follows: <hr> "VoltMaster Equalizer Operation In many 24 volt electrical systems, it is desirable to tap into the battery system to obtain power for 12 volt loads. This method, while seemingly simple, causes a charge imbalance resulting in Battery "B" being overcharged, and possibly boiling, while Battery "A" discharges. To solve this application problem, the Vanner VoltMaster battery equalizer is connected to the battery system at the +24, +12 and ground points. The battery equalizer maintains the voltage balance and charge acceptance rate of each battery to within 0.1 volts under light loads and within 0.5 volts at full loads. When the voltage of Battery "A" is higher than that of Battery "B", the battery equalizer is in standby mode - meaning it is not transferring power from its 24 volt input to its 12 volt output. When a 12 volt load is present, and Battery "A's" voltage decreases to just below the voltage of Battery "B", the battery equalizer activates and transfers sufficient current from Battery "B" to Battery "A", satisfying the load and maintaining an equal voltage and charge in both batteries." http://www.dan-marcrvparts.com/vo12vobaeq.html <hr> Vanner now makes a "converter / equalizer" that replaces some of the older technology. The reasons they discontinued the older technology should be self-explanatory, at this point. http://www.abc-companies.com/servicebulletins/SB1212_Vanner_70_M_Series_battery_equalizer- d.pdf The basic equalizer is only suited for very basic needs, just as the typical battery isolator is. If a user requires heavier use of 12vdc, then a basic equalizer is not a good choice; a 24 to 12vdc converter, is. In fact, a seperate 12vdc alternator, and battery bank, would be the ideal solution, with a converter backup. (Man, did we beat this puppy to death, or what?) Cheers! | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1474 Registered: 12-2000 Posted From: 76.66.16.72 Rating: N/A |
Nope, all good info. Best to remember, in commercial service, the bus is used when it is running. In busnut service, the bus gets used when it isn't running. Contradiction is built in. happy coaching! buswarrior | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 754 Registered: 7-2006 Posted From: 72.146.76.92 Rating: N/A |
Re: "Contradiction is built in." Yeah, it is, BW. It's easy to forget that the commercial rig was designed for daily use. Using any commercial rig as an occasional recreational vehicle, wasn't in the original engineer/designer's plans. Since most all of the ancillary equipment was also originally designed for commercial use, failures should be expected, if the usage differs too greatly. Oh well... It still beats the "stick and staple" garbage! Stay warm, eh? | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1475 Registered: 12-2000 Posted From: 76.68.120.212 Rating: N/A |
10-4, garbage and warm! happy coaching! buswarrior | ||
| Chuck Newman (Chuck_newman)
Registered Member Username: Chuck_newman Post Number: 289 Registered: 1-2005 Posted From: 76.246.254.144 Rating: N/A |
Nellie, don't get confused by the technical jargon. Bottom line is simple: Using an equalizer when you're parked and not charging the batteries, you are drawing 12vdc from only 1/2 of your 24vdc battery bank, be it 2 batteries or 20. Period! Vanner used to have a very clear diagram on their site that showed this, but got lost in their web modernization. I can email you a copy if you like. With a converter in the same scenario you are drawing from all the batteries. The other problem here is either device ain't cheap. Two years ago some dealers had them on sale for about $900. each. I found new ones on eBay for $66. to $300. If your bus does not already have "house" wiring installed, John's alternative of 12vdc batteries and separate alternator has been used by many with success. Also, when someone says "...it won't work...", ask them for a detailed explanation why it won't work until they can substantiate their claims. | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1253 Registered: 5-2001 Posted From: 65.74.69.188 Rating: N/A |
I Dunno, Chuck. I carefully read John's post with the language from Vanner's dialog, and it looks to me as though it is saying that the Vanner will pull from all batteries, even when there is no charge on the batteries. The part that John put in bold seems to be saying that the Vanner doesn't work in reverse; that is, if the 12 volt terminal is a bit higher than half of the 24 volt terminal, then the Vanner goes into standby mode. Makes sense to me. In any case, if I ever have a reason to deal with one, I will probably take some very careful measurments of what is happening and act according to what I find. For what it's worth. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 757 Registered: 7-2006 Posted From: 72.146.76.23 Rating: N/A |
Note the "note" at the end. General Description The Vanner VoltMaster Battery Equalizer is an efficient and highly reliable method of obtaining a 12 volt DC power source from a 24 volt DC electrical system. The equalizer makes the batteries look like they are in series and parallel at the same time. In addition to providing regulated 12 volt power, the system ensures that battery voltages remain equal which significantly extends battery life. Ideally suited for vehicle and alternate energy applications, the VoltMaster Battery Equalizer is designed to save your batteries and the money you would spend replacing them. Users of the Vanner VoltMaster Battery Equalizer know that it is the most cost effective and dependable solution for dual voltage systems. A typical system would include a 24VDC power source, such as an alternator or solar array, two 12 volt battery banks in series, and the VoltMaster Battery Equalizer. The Battery Equalizer connects to the 24 volt, 12 volt and ground terminals of the battery system. When the 12 volt loads require power, the Battery Equalizer ensures that the current is taken equally from both batteries, and that the voltages of the two batteries are kept equal. This equalization ensures extended battery life and provides a stable 12 volt supply for operating accessories. Parallel Equalizers: Models are available which provide 10, 20, 60, 80 and 100 amps of 12 volt DC power. VoltMaster Battery Equalizers may also be operated in parallel to provide more power. For example, two 60 amp units can be installed to provide 120 amps of 12 volt DC power. Family 1, Family 3, Family 4, and Family 5 models may be paralleled in any combination. Family 2 models may be paralleled only with other Family 2 models. NOTE: The Vanner VoltMaster Battery Equalizer is an extremely reliable device and, when installed according to the instructions, will provide reliable operation for an indefinite period of time. However, if a system abnormality should develop that would cause a Battery Equalizer malfunction, damage to the battery system could result if 12 volt loads are present. If your system application is critical you may consider installing a Vanner Model EM-70 Electrical System Monitor. This module monitors the battery system's voltages and balance, and provides fault signals that can be wired to warning lights, buzzers or other control/warning devices. Models 60-50M , 60-60M and 65-60M have the EM-70 built in. Call Vanner for more details. From: http://www.vanner.com/client/images/manual_Battery_Equalizer.pdf In simple words: it's great product when both batteries are good, and the charging system works as it should, otherwise, all bets are off. For the price of all that, it'd be cheaper to use a center tap, and buy a new battery every 6 months. Cheers | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1254 Registered: 5-2001 Posted From: 65.74.69.188 Rating: N/A |
Thanks, John. I would say that the note clears up what you were saying. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska |