I'm pulling my hair out (singular, not plural anymore) over how to use the alternator on my bus to charge my house batteries----without cooking the start batteries. I have a Newmar 1-2-120 battery isolator but I can't use it because my alt requires a tickle from the battery to energize. I've contemplated simply adding a switch to direct power from the alt to the house batteries but I'm afraid that will cause my 110 amp alt to over charge the start battery. So now I'm thinking about a switch that will isolate the start batteries at the same time it engages the house batteries. I'd purser this idea by simply disconnecting the battery with the engine running to see if it kept running but I'm worried about blowing something out--like the computer. Any Ideas? Jack
A quick refresher on battery charging. The voltage applied to the battery for charging determines how much current can flow into the battery. What is the alternator voltage with the engine running? That is your charging voltage. "12VDC"
systems charge at 13.7 to 14.4 VDC. Double that for a "24VDC" system. The size of the alternator does not effect battery charging, except in a negative way of not supplying sufficient current for the correct charge. I charge with 50DN alternator, 250A at 28V. I have seen a charge at 150A that tailed off to about 80A within 30 or 40 seconds as the battery voltage increased.
BTW that fancy battery isolater causes the charging voltage to be anywhere from 0.5 to 1.0 volt low. Best is to have a relay, at least a 200A continuous rating(I prefer 400A).
Think about installing a Battery Monitor, I think Trimetric is the only one available. That will show you voltage, current, state of charge, amp hours positive and negative, cumulative amp hours, number of cycles. If you are using wet cell lead acid batteries then the hydrometer will become your friend.
Bill
Get a sensing isolator or a battery separator www.texasindustrialelectric.com can fix you up
A Xantrex auxiliary charger (used to be called an "Echo" charger) may work for you.
http://www.xantrex.com/power-products/power-accessories/auxiliary-battery-charger.aspx (http://www.xantrex.com/power-products/power-accessories/auxiliary-battery-charger.aspx)
See what you guys think of this idea:
Most alternators have a diode pack for the rectifier. IDK, maybe these have individual diodes. They are a 3 phase full wave array, meaning for each of the 3 field windings (with ends paired) one diode will direct - to ground while one directs + to the battery, x3 = 6 diodes.
So, if you want to charge 2 battery banks you could just get an extra diode pack and connect them in parallel then run the output of one to each battery bank. (proper heat sinks and all of course) So much for the output side. Whichever bank has the lowest charge will get the most current. For the control side hook your sense wire to the bank with the largest loads and both will be charged to full voltage, or you could get fancy with it and build a circuit that will send the lower of the two voltages to the alternator. Might need a transistor or two for that one.
Or just install a battery switch from a boat with the sense wire at the output and manually switch over. 1,2 or Both.
Jim
Thanks for all the responses!
Brian, your refresher course was well stated. I had checked the voltage output and it is 14.4v. In fooling with the isolator I did observe the voltage drop you mentioned and sort of shined it on as part of the cost of doing business. It looked to me like even with the drop the voltage was still "within" the normal range--though it would make getting a full charge less likely in the short term. I had to laugh at myself over my post. I jumped in as if I'd been discussing all this with you all and assumed we'd discussed the fact that my charging system was up to snuff.
Bob, Xantrex does make quality products--though expensive. I went to their web site but I didn't find a device that could be powered by an alternator--did I just miss finding it? Right now I use a Progressive Dynamics 9245C three stage power converter to charge up my house batteries when I am on shore or genny power. Many people run their generators while driving but I'm a little skiterish about that hence the interest in using the alt.
Jim, I like your idea about the extra diode pack and will give it some study but in all honesty and in keeping with KISS, the three way switching idea most appeals to me. My question there is: is the sense wire you refer to the same as the exciter wire to the alternator?
Clifford, the sensing isolator you pointed out looks like a good option. I'll find a wiring schematic for it and look at it next to the charging schematic for my bus and see if I can tell if they will play nice together.
Jack
If you want simple and effective you should look at this:
https://www.sterling-power-usa.com/SterlingPower12volt-12volt-30ampbatterytobatterycharger.aspx
Also available in a 60-amp version.
We use one to charge our 12v house batteries from our 24v chassis alternator. Only works when the alternator is making power. The wonderful thing about this type of device is that it is a true multi-stage charger and it will provide a proper charge for your house batteries regardless of the situation on your chassis batteries. The chassis batteries will continue to function as before and will be charged with the chassis alternator/regulator.
We've got ours set up so that I have to flip a switch to make it work, but it can be wired so that whenever it senses the chassis alternator charging it will send a charge to the house batteries.
I'm not sure Jack. I've not been into a bus alternator so I'm not certain how the voltage regulator is set up. Typically though the regulator will output a voltage/current signal to the rotor winding to control the level of output, I'm most familiar with that being referred to as the exciter. Whereas the regulator also has an input directly from the battery which tells it the battery voltage, usually referred to as the sense lead. The value of a dedicated wire for that is it results in higher charging voltages. You can tell what it is by where it goes and then apply the relevant bus conventions. (The regulator often also has a control input from the ignition which switches it on, often configured to light a fault lamp in case of a failure. This is not the sense lead.)
My only concern with this setup is, what happens when one bank is fully charged and the other is fully discharged? Say you are sensing from the fully discharged bank so you get full current from the alternator. The voltage differential means most of that charge would go to the bank that needs it, but without question some would go to the fully charged one. How much is a math problem, based on the relative voltages and resistances of the battery cables. That could be worked out and if the level was low enough it would be acceptable. I don't have that answer, at least not right now. It's been a long time since I worked with those formulas and I'm rusty. But it isn't a complex calculation, just simple math. It has to be set up right.
The downside of a manual boat switch is location, but more expensive remote switches do exist. Ideally you would control it from the driver's seat. But by that point why not just use the existing solutions? They are probably nearly as cheap, and proven.
Jim
This question was posted several years ago and someone who seemed to know what he was talking about stated that if a mixed batch of batteries, some charged and some discharged; that the charged ones would not over charge but the weak ones would charge and all even out.
That is, if they were all good batteries to begin with. I know if you have a bad one it will boil out and you will smell it.
Quote from: oltrunt on September 17, 2018, 09:49:05 AM
Bob, Xantrex does make quality products--though expensive. I went to their web site but I didn't find a device that could be powered by an alternator--did I just miss finding it? Right now I use a Progressive Dynamics 9245C three stage power converter to charge up my house batteries when I am on shore or genny power. Many people run their generators while driving but I'm a little skiterish about that hence the interest in using the alt.
ICBW but my understanding is that the Echo charger doesn't care where the "surplus" charge comes from. I used one on my boat for 7 years to keep the genset battery charged. I never replaced that battery, never charged it other than through the Echo charge (no genset charging to its own battery) and literally just ignored that battery. In my defense it was in kind of an ignorant place so it was easy to ignore. As far as I know it charged both underway off the engine alternators and on shore/gen power but to be honest I never measured it so I can't be 100% sure of that claim. Considering how it was wired however there is no way it could tell if the battery charge was coming out of the inverter or from the engine alternators.
In addition to the battery-to-battery charger I posted about earlier, we also use a Xantrex Echo Charger to keep our generator start battery topped off. It can send up to 15 amps from one battery bank to another. The way the manual shows it being connected is to have the house battery bank as the main supply, with the 15-amp output going to the start batteries. In that configuration, whenever the house batteries are being charged up to 15 amps can be used by the start battery to charge.
I don't see any reason why you couldn't turn it around the other way to use the chassis batteries to charge the house batteries. However, you'd be limited to a 15-amp charge. If you really ran down your house batteries overnight and tried to use the Echo Charger to charge them, I'm not sure if 15 amps will do it.
There is one other big drawback to the Echo Charger - if the differential between the two battery banks is too great (house batteries really run down) the Echo Charger will not send a charge through. That's happened to us a few times when we had trouble starting the generator and ran down the generator start battery. The Echo Charger wouldn't send a charge through.
I finally installed a switch to bridge the generator start battery to the house batteries so that I can bring up the charge on the generator battery until the differential is smaller. I don't like to leave them connected during normal use though, as the generator start battery is the only way we'd be able to start the generator if the house batteries inadvertently were run down too far.
Thanks Richard. I queried the mfg as to why when the unit was set in SVEM mode in cold weather there was a chance of the input battery not being charged enough to start a vehicle. I also asked if the BB1230 model would work with my 110 amp alternator. I'll share what I find out.
Jack
Quote from: oltrunt on September 17, 2018, 02:51:19 PM
Thanks Richard. I queried the mfg as to why when the unit was set in SVEM mode in cold weather there was a chance of the input battery not being charged enough to start a vehicle. I also asked if the BB1230 model would work with my 110 amp alternator. I'll share what I find out.
Jack
I'm going to PM you the US contact I have for Sterling. Not sure if you were aware of the US office or if you were trying to contact them in the UK.
About the SVEM mode - the answer is quite simple. By default, the unit is set to send a charge through to the house batteries only when the voltage is high enough to indicate that the chassis alternator is charging the chassis batteries. Usually when operating on the road the engine RPMs are elevated and there is no problem. The SVEM (Stationary Vehicle Engagement Mode) sets a lower threshold for the unit to send a charge to the house batteries, allowing the house batteries to be charged even while the engine is idling. Depending on the function of your particular alternator at idle, it may not be providing adequate output to charge batteries. By forcing the unit to send a charge through, you run the risk of powering the charger from the chassis battery instead of from the chassis alternator. Do this for too long a time and the chassis batteries can be run down to the point they won't restart the engine in on a cold day. Guess they figure you're better warned than not.
I installed ours using the ignition input mode, but instead of connecting the lead to the 'ignition' circuit I connected it to a switched power source. That allows me to turn the battery-to-battery (BTB) charger on whenever I want, or turn it off just as easily. I can override the minimum voltage threshold if I want, or if I know the chassis batteries to be weak leave the unit off and allow the chassis alternator's full output to go to the chassis batteries.
I don't see any reason that unit would not work on your alternator, unless of course you don't have 30 amps to spare. You'll have to do the math to see what else is drawing power from the chassis system while you're running down the road. If you're running an inverter or other high-current devices you might have a problem. I'm running the 50DN on my bus, so the current draw (35 amp @ 24v outputting 70 amps @ 12v) isn't a concern. At least it hasn't been yet.
I'm actually surprised that more people aren't running BTB chargers like this. There is a slight efficiency loss, but almost any method other than the most simple will have some amount of that. Seems like the boating world has been doing this for a long time. I love the idea because it allowed me to keep my house and chassis systems totally separate and yet still charge one from the other.
Quote from: luvrbus on September 16, 2018, 08:23:30 PM
Get a sensing isolator or a battery separator www.texasindustrialelectric.com can fix you up
HI;
Nice selection of relays. I have a battery isolator and always wanted to add a relay.
The relay could combine the house and start batteries when in a fix.
Thanks, Merle.
If it were me i would go with a big boy relay and a bi-directional charging relay. When either bank is being charged (ie. Running the engine or being plugged into shore power) the relay will automatically engage and charge the other bank. You can buy one with or without an auxiliary start feature built in. (It's really easy to just wire in a manual switch yourself without that option.) The relay control will automatically engage and disengage at preset voltage levels to prevent accidental discharge of the wrong bank.
Quote from: thomasinnv on September 18, 2018, 08:46:07 AM
If it were me i would go with a big boy relay and a bi-directional charging relay. When either bank is being charged (ie. Running the engine or being plugged into shore power) the relay will automatically engage and charge the other bank. You can buy one with or without an auxiliary start feature built in. (It's really easy to just wire in a manual switch yourself without that option.) The relay control will automatically engage and disengage at preset voltage levels to prevent accidental discharge of the wrong bank.
What happens if the two battery banks are at very different state of charge. Wouldn't the battery bank with the higher state of charge end up being over-charged? Or, would the high state of charge of the one bank cause the regulator to reduce the charge prematurely? I've always liked my house batteries to have a multi-stage charger connected to them - would the regulator in the bus work the same way?
It all seemed so simple until my mind got all twisted up in this thread. My setup and thinking goes like this, please tell me I'm ok or an idiot.
Setup: Single heavy duty high current manual switch between house and start battery banks.
Use:
> If the house bank needs a charge and bus is on the go, I connect them so the bus alternator charges both banks.
> When parked and boondocking, disconnect the banks to protect the start battery from unnecessary discharge.
> If start battery is low, connect together to give starting an extra boost from the house current. > Backup plan - connect battery banks, start generator, enable inverter/charger mode, take a nap or go have a coffee. Start bus.
> Backup plan part 2 - generator battery is dead, SOL. :-*
That's a lot like the manual boat switch since you can use it to bridge the banks at any time.
Jim
Quote from: windtrader on September 18, 2018, 10:15:36 AM
It all seemed so simple until my mind got all twisted up in this thread. My setup and thinking goes like this, please tell me I'm ok or an idiot.
Setup: Single heavy duty high current manual switch between house and start battery banks.
Use:
> If the house bank needs a charge and bus is on the go, I connect them so the bus alternator charges both banks.
> When parked and boondocking, disconnect the banks to protect the start battery from unnecessary discharge.
> If start battery is low, connect together to give starting an extra boost from the house current. > Backup plan - connect battery banks, start generator, enable inverter/charger mode, take a nap or go have a coffee. Start bus.
> Backup plan part 2 - generator battery is dead, SOL. :-*
That would certainly work and allow charging of house batteries on the road. We went with a more complex system because I wanted to have a multi-stage charger on the house batteries which monitored them separately from the chassis batteries and charged them accordingly.
I'm quite enamored with the Sterling BB 1230 battery to battery charger and am about one key stroke from buying it. My only hesitation is that I'm not sure that the system can keep my start batteries from over charging. I can't seem to find definitive assurance that this won't happen. Jack
Quote from: oltrunt on September 18, 2018, 07:26:03 PM
I'm quite enamored with the Sterling BB 1230 battery to battery charger and am about one key stroke from buying it. My only hesitation is that I'm not sure that the system can keep my start batteries from over charging. I can't seem to find definitive assurance that this won't happen. Jack
When you say 'keep my start batteries from over charging' I assume you mean that you're worried about depleting your chassis start batteries while trying to charge your house batteries.
There are a few ways to connect these to prevent that from happening.
1 - Out of the box they are set to pull current from the chassis system only when the alternator is putting out current and charging.
2 - You can set the Sterling to come on manually with a switch on the dash that you flip when you want to charge the house batteries.
3 - You can connect a lead to the Sterling which is powered only when the chassis alternator is charging and use that to trigger the charge on the house batteries.
All that said, you've got to do the math to be sure that your alternator output is adequate to power your current needs PLUS the 30-amp draw that is possible from the Sterling. Of course, this caveat will apply in any situation you use. The Sterling will only pull its full 30 amps when your house batteries are depleted. But so will any method you use to connect your house batteries to your chassis system - if your house batteries are depleted enough to draw 30 amps they will.
Thanks Richard. It is my understanding that a fully charged battery can be damaged when given continuous high charge such as when the charger is trying to charge a very low (or damaged) battery. It is that I am trying to avoid. Jack
Quote from: oltrunt on September 19, 2018, 06:27:21 AM
Thanks Richard. It is my understanding that a fully charged battery can be damaged when given continuous high charge such as when the charger is trying to charge a very low (or damaged) battery. It is that I am trying to avoid. Jack
The Sterling battery-to-battery chargers do not supply any charge to the chassis start batteries, so there is no way that damage to them could be done unless something goes drastically wrong. The charging circuit in the Sterling is multi-stage and will adjust the voltage as needed to keep from roasting the house batteries. It is possible to set custom voltage levels for the stages if the pre-set ones don't work for you. Be prepared to sit and study the manual for quite a while. It's not terribly intuitive, and it's packed with so much information that it is not a quick read.
You're right about the manual not being very intuitive but I see no reason why it should be. I've read it several times and as far as it goes it makes sense. I've also studied all of the videos offered by Sterling and they too make sense. The thing I'm having trouble with is that the start battery is in the flow of the alternator output at all times whether or not it is in need of a charge and regardless of the charge rate set by the BBC for the house batteries. When the BBC is demanding high alternator output, the start battery receives that alternator output on its way to the device. I'm probably overthinking this but i'd still like a definitive answer. Jack
this will not help but I have 2 like this right at the top of my dash on the left corner . 1 for coach and 1 for start batteries .
I can see them from outside and I leave them on at all times so I can see the voltage at any time
https://www.amazon.ca/DROK-DC2-5-30V-Waterproof-Digital-Voltmeter/dp/B00CK3P20S/ref=sr_1_9?ie=UTF8&qid=1537374774&sr=8-9&keywords=12+volt+led+meter
dave
:o
dave
Quote from: oltrunt on September 19, 2018, 08:55:39 AM
... The thing I'm having trouble with is that the start battery is in the flow of the alternator output at all times whether or not it is in need of a charge and regardless of the charge rate set by the BBC for the house batteries. When the BBC is demanding high alternator output, the start battery receives that alternator output on its way to the device. I'm probably overthinking this but i'd still like a definitive answer. Jack
How would that be any different from turning on any other load in the coach's electrical system? The coach's alternator & regulator will just see it as a load and adjust accordingly. I had the same problem overthinking this too, until I started to just picture the BBC as a load on the system and nothing more.
You turn on the bus headlights, and suddenly there is a large load. The regulator & alternator adjust. Turn on the OTR a/c and there is a huge load. The r & a adjust. Turn on the BBC charger with its 30-amp load, and the r& a adjust. If the r & a are working properly, they should adjust to suit the increased load and nothing more. Coach batteries shouldn't notice any difference from any other load on the system.
"I had the same problem overthinking this too, until I started to just picture the BBC as a load on the system and nothing more." Hum---- that's a good way to look at it.
Dave. Two meters like you have would certainly give me my "definitive answer".
Thanks, Jack
We've got a Victron battery monitor on our house system. It has a shunt on the negative post of the house battery bank, and all current to/from the house batteries flow through this and are monitored.
Watching the readout has been educational. If the 120v charger is turned on and I'm in storage/maintain mode, the voltage on the house system will be 13.2v and the current flow through the battery will be zero or nearly so. If I turn on a 12v appliance the current will go up to reflect the new load on the batteries. Within seconds of it going up, it will again start going back to zero as the charger increases its output to compensate. It's a very well-coordinated dance between the loads and the charger. The voltage will stay the same the entire time (and will depend on what mode the charger is in.)
Why do I mention all this? Because my suspicion is that if you put the voltmeter in either of the circuits it may not provide the information you're looking for. It's possible for the current flow to increase but the voltage to remain the same. My 120v house battery charger (PD9270) will adjust the mode according to the state of charge of the batteries. The voltage on the house battery side when the BBC is running should be whatever the particular mode is set for (bulk, float, maintain, etc) in the BBC, and the mode will likely adjust itself as needed to accomplish proper battery charging/maintenance.
I'm not at all an expert on the inner workings of a bus voltage regulator as it works in these situations. Does the voltage always go up when it needs to supply more current flow? My suspicion is that as long as the chassis batteries have a good state of charge the current flow will increase but the voltage will stay the same. If the batteries were partially depleted the voltage would go up AND the current flow to the batteries would increase regardless of the external load on the batteries.
Maybe someone with more understanding of the regulators on a bus can confirm my theory, that the voltage output to the batteries increases as the voltage level (state of charge) of the batteries is decreased.
Quote from: richard5933 on September 18, 2018, 08:53:58 AM
What happens if the two battery banks are at very different state of charge. Wouldn't the battery bank with the higher state of charge end up being over-charged? Or, would the high state of charge of the one bank cause the regulator to reduce the charge prematurely? I've always liked my house batteries to have a multi-stage charger connected to them - would the regulator in the bus work the same way?
The bank with the lowest soc is going to absorb the bulk of the charging current. As the voltage rises the amperage ansorbed goes down. If you were to place an amp meter between the alternator and the battery you would find that a fully charged battery will be "pulling" just a few amps at say 13.5v whereas a heavily discharged battery will be pulling close to the rated output of the alternator at the same voltage. The amount of amperage a battery will absorb is related to the soc of the battery and the charging voltage being applied. The voltage regulator connected to your alternator is just that, a VOLTAGE regulator. Technically, the charging amperage is not limited, except for the output limitation of the alternator or as a factor of the output voltage in relation to the soc.
The type of system that I mentioned before is found in probably 99% of stick and staple diesel pusher rv's on the road. Simple, inexpensive, and works very well. No sense in over thinking things or trying to reinvent the wheel.
Wow you guys can make something so simple into a engineering feat.Knowing Jack for several years I am willing to make a small wager he makes what he has on hand work being he is sorta thrifty and smart too.lol he is probably still licking his wounds for the telephone up grade to use Tap Talk that is no longer here ;D Jack I still have my $29.00 ZTE phone BTW.Batteries will self equalize I can charge my starting batteries on the MCI and the battery light will come on if one has more charge volts and only 1 head light will come on. Go back in a couple of hours the head light comes on and the battery light is out and both batteries have the same voltage
Well, there's a charging curve for the batteries between voltage and current. It's a logarithmic curve which just means it gets steeper a lot faster as the voltage drops more and as the voltage gets higher it changes slower. Not that that's a big deal, the important thing is that charging voltage is always a little higher that the battery's static fully charged voltage under normal conditions.
Actually any battery in good condition should at least theoretically read the same voltage regardless of the state of charge. They don't because of internal resistance, leakage and current flow in the testing meter. So it doesn't take a big change in voltage to get lots of current moving. I think that's all stuff that we all mostly understand. The reason we usually see larger differences in battery voltages is on account of the various loads on the battery, and the less internal resistance there is the less the variation when a load is increased or decreased. So now, no two batteries are going to have the same internal resistance. So if you apply a charge across them one will naturally tend to take more charge than the other. It may not be much or it may be a good bit. Variations in the charging voltage can overcome that and even it out and that's what a top notch charging system which takes current into account will do.
As you get closer to full charge where the current drops off this internal resistance may mean that at a given charging voltage one battery draws a maintenance charge, just enough to overcome minor losses whereas another may draw enough to slowly deplete the battery acid. Again, they both achieve the same full charge voltage, that's based on the atomic chemistry of the dissimilar metals and has to be the same but the internal resistance is what cuts down the current flow and that is based on physical construction and can vary quite a lot. So a really good charger will monitor the voltage as well as the current and reduce current flow to a maintenance level when the full charge voltage is achieved regardless of what the battery internal resistance is doing.
Lesser devices, and the alternator's voltage regulator is one of those lesser devices in most cases, simply provide charging based on the battery voltage and bring it up to a level that insures that the average generic battery will get an average generic full charge and this works pretty well on the road. But for a full time static installation that's pretty rudimentary and means you have to keep an eye on electrolyte levels and ph. All of which is entirely doable. So it's mostly just a question of whether you'd rather watch your batteries or buy fancy chargers.
Jim
Jim that made me laugh good naturedly-never mind the spelling, I am after all "ol trUnt! At best all I am going to be able to do is try to maximize voltage in and voltage out without cooking my batteries. I think (hope) BBC is the way to go. After the $310.10 BBCC purchase ( more here in Kalifornia because I'm paying for the bullet train and the moon probe (or whatever), I'm still excited by the prospects.
So whats another $300. The guy at the battery store informed me that my four and a half year old batteries are down to 50%. Apparently they don't owe me anything so OH WELL.
I talked to wiffy and despite the cost it isn't any more than a couple of nights at the lodge hotel in Yosemite--and the bed is better in the bus. Leaving for Yosemite on Oct first---Whoopie! Jack
QuoteLeaving for Yosemite on Oct first---Whoopie! Jack
And where do you go in the winter?
It's funny really, any of the new Lithium batteries will have an inexpensive and very sophisticated charger *and* a very sophisticated discharge regulator because they don't tolerate any abuse, but can we get that for lead acid batteries? HA!
Jim
Battery wise I have 2-31 starting batteries and 2-8D Lifeline AGM house batteries. Engine has a Delco 50DN 300amp 12v alternator and also have a Trace 2512 inverter charger with 130amp 3 stage charging.
To jump the two banks of batteries, I have 2-150amp continuous relays (look like Ford starting relays) paralleled together with a heavy metal strap. I have an on-off-on switch so the relay can be controlled either by the ignition switch, or manually powered by the house batteries. Then I can either charge my house batteries going down the road, or jump start myself if the starting batteries are low. Simple, and been 100% reliable for 24 years. Good Luck, TomC
I have something similiar. Can use house batteries to assist engine start and also coach batteries to assist generator start.
Such a fuss in my little bus. I have 2 group 31 start batteries, 2 Trojan GC house batteries and 1 group 24 battery to run the air compressor and start the genny. The 24 is linked by a manual switch to the start batteries so it can be charged by the 110 amp alt if it gets low.
Since I want the house batteries "Smart Charged" while driving I'll spend this weekend installing a Sterling BB1230 unit. While I'm at it I'm replacing the stationary battery tray with a roll out version--should have done that when I built the bus. Jack
From the nothing is ever simple file:
I read stuff upside down just as easily as right side up--great for parties when I was a teen. Not so great now. I'm working on a roll out system for my battery drawer. I'm getting too old to be lugging golf cart batteries off a tray that sits well inside the body line. I picked up a pair of triple slide drawer slides rated for twice the load I intend to have. I had to weld brackets to the slides to make things work. The tray slides in and out at about a 40 degree angle. I drew up some plans and got to welding. I welded up the right side and it all worked just fine----so I welded up the left side the same way. Ah S*&#! The left side is the mirror image of the right but not when you read things upside down!?! The brackets were where I wanted them. just backwards so I decided to reverse the direction of the slide rather than risk destroying the whole thing with a grinder. I figured out how to get the slide apart. All those TINY ball bearings and two sizes to boot. Six hours later and completely cross eyed I got the slide back together--backwards--it works. Tomorrow I'll finish the installation. I won't draw any plans, I'll just build.
Jack
Quote from: oltrunt on September 22, 2018, 06:49:59 PM... Six hours later and completely cross eyed I got the slide back together ...
Pictures, please??
Ha! they all turned out upside down. I'll post pics tomorrow. Jack
I got the battery tray finished and tested today--it works. Jack
(https://i.postimg.cc/qRKqzbDN/20180923_140300.jpg).
(https://i.postimg.cc/FzQRcywD/20180923_135502.jpg).
(https://i.postimg.cc/nrYL1sJZ/20180923_135530.jpg)
Looks good Jack,my 8D's are so heavy I am building mine using the Smith Cam Followers type rollers
OR, just get the factory roll out battery tray from a 4905.
Quote from: oltrunt on September 23, 2018, 06:24:37 PMI got the battery tray finished and tested today--it works. Jack
Nice work - it sure does! I like that setup. I was moving my batteries, partly because of some floor/frame corrosion (and also to get them closer to the engine by a lot) a few years ago. The welder I had hired to repair the floor frame said "I can build you a roll-out battery box". I turned my back and he had welded up a 60 pound frame with ball bearing rollers built in. About last year, I looked at that and said "that tray sets the bottom of the battery 3 1/2 inches above the floor -- if I made a pair of simple metal slots that contain 2-3 rollers each, I can cut 45 pounds off the bottom of that tray and make the bottom of the battery 5/16" of a inch off the floor and gain space I need". (3 Type 31 batts.) I'm gonna do that when my tuwit arrives.