Dump Trailer Battery

[grsthegreat]

i used a 5 amp trickle charger that mounts thru face of battery box. all i do is lift the lid and plug in extension cord. takes 3 seconds after i unhook trailer. my battery is 5 yo right now....still 100% according to my midtronics tester.

 

[nyone]

Hard wireing also keeps neighbors and friends from borrowing it.

I had a hardwired set of anderson plugs for a trailer or a rear vehicle mounted winch. I did alot of heavy pulls with that setup with just the vehicle idling.

 

[LD1]

what LD1 described is what I was talking about doing, have you had any regrets maybe something you would have done different?

Yup. That I didnt do it sooner

 

[jaxs]

What I'm not understanding about so called "hardwiring"is with 3 batteries 1 is going dead,how removing 1 battery leaving 2 batteries to do the work of 3 is an improvement. It would seem logical to add a 4th battery if 3 isn't doing the job. I'd far prefer a discharged trailer battery over discharged truck batteries. Some fuel injection systems are damaged when operated on weak batteries. Nothing beats experience so I'll ask if anyone can tell us what the fine is for disabling break-a-way brake system and/or what the out come was where a trailer broke loose and collided and investigation revealed disabled brake-a-way? I'll be first to admit doing some Rube Goldbergs but never with as many negatives simply to save buying a battery.

 

[woody]

i used a 5 amp trickle charger that mounts thru face of battery box. all i do is lift the lid and plug in extension cord. takes 3 seconds after i unhook trailer. my battery is 5 yo right now....still 100% according to my midtronics tester.

View attachment 755222

My trailer had one of those and it went bad, got to where it would start charging when I plugged it in but would not fully charge the battery so I started using a different charger works fine a little inconvenient but works. I rotate a couple of deep cycle batteries the one in my trailer and the one in my gate which only has a solar charger on it and with the trees full of leaves it does not get fully charged from the solar so I rotate it out every couple months.

 

[LD1]

What I'm not understanding about so called "hardwiring"is with 3 batteries 1 is going dead,how removing 1 battery leaving 2 batteries to do the work of 3 is an improvement. It would seem logical to add a 4th battery if 3 isn't doing the job. I'd far prefer a discharged trailer battery over discharged truck batteries. Some fuel injection systems are damaged when operated on weak batteries. Nothing beats experience so I'll ask if anyone can tell us what the fine is for disabling break-a-way brake system and/or what the out come was where a trailer broke loose and collided and investigation revealed disabled brake-a-way? I'll be first to admit doing some Rube Goldbergs but never with as many negatives simply to save buying a battery.

Its all in how a dump trailer is integrated with the truck.

A dump trailer has its OWN deep cycle battery. And when dumping the trailer....it draws its power from its OWN batter and NOT the truck batteries.

The reason is because the truck is only wired with a 10ga or 12ga hot wire back at the trailer connection. This is not even close to big enough to run a dump trailer pump. All it is there for is to recharge the battery between dumps.

Most "better" dump trailers have a breaker or isolater/relay that will disconnect the truck when dumping the trailer. Because if the dump trailer batter starts getting low, it will try and pull its ~200 amps of power from the truck on that little 10-12ga wire. And the end result is blowing the 30 or 40amp fuse in the truck. Seen it many times. And most people dont even know they blew that fuse.....because all it powers is the 7-way AUX 12v pin. Then they wonder why their trailer battery isnt charging when connected to the truck anymore.

Cheaper dump trailers that dont isolate the truck....you are supposed to unhook the 7-way before dumping to prevent this from happening. Its usually in the owners manual of the trailer as well....but who ever reads those.

The "hardwire" is running cords of sufficient gauge (2ga usually) From the trucks batteries to the trailer to be able to dump off the trucks batteries alone and not even need the trailer battery other than for breakaway protection.

So its not a matter of trying to have 2 batteries do the work of 3. Its more like having two batteries + alternator try and do the work of ONE isolated deep cycle battery. Which it does with ease.

Look at most of the 350/450 class trucks that have a dump bed on them. They use the EXACT SAME pump/hoist setup as most of the dump trailers. And they are hardwired right to the truck batteries. Dump trailers arent hardwired because they are made to be disconnected and used on multiple vehicles. So they try and make the unit self-contained....IE: deep cycle battery

 

[woody]

What I'm not understanding about so called "hardwiring"is with 3 batteries 1 is going dead,how removing 1 battery leaving 2 batteries to do the work of 3 is an improvement. It would seem logical to add a 4th battery if 3 isn't doing the job. I'd far prefer a discharged trailer battery over discharged truck batteries. Some fuel injection systems are damaged when operated on weak batteries. Nothing beats experience so I'll ask if anyone can tell us what the fine is for disabling break-a-way brake system and/or what the out come was where a trailer broke loose and collided and investigation revealed disabled brake-a-way? I'll be first to admit doing some Rube Goldbergs but never with as many negatives simply to save buying a battery.

Okay the trailer has a battery of it's own it only gets a trickle charge from the truck so it dumps the trailer until it don't. without removing the trailer battery I was going to connect the truck batteries in parallel to the trailer adding 2 more batteries to help with the load. In my thinking this would give me 12VDC but more amps available and the truck would recharge quickly due to the alternator running at full charge instead of a trickle charge as it is now. I always start the trip with a fully charged dump trailer battery but sometimes it just does not last and that depends a lot on the load. Hope this helps and hope I am correct in my thinking. The trailer breakaway would still be connected to the trailer battery.

 

[woody]

LD1 we must have been typing at the same time.

 

[jaxs]

Ld1 and Woody,I didn't ask how the OEM system works,I said I don't see this modification improving on the OEM. The hardwired I referenced is that in LD1's example. Thank both you for all the words explaining how this works but I'm afraid there's flaws in you reasoning. I don't care to undertake breaking all of this down but will point out a fairly simple point for each of you. LD1 those truck batteries aren't loafing along just for the ride,to start the diesel engine they need to be at or near 100% full charge any time truck is started. If a dedicated trailer battery is discharged over a period of X ,the 2 truck batteries will 50% discharge over the same period (2 batteries shouldering the job of 3).
Woody,the 10 guage wire commonly used for battery and ground in 7 way is capable of 30 amps continuous and 40 amps interment. If 7 way has 12 guage at those positions,it's reccomend upgrading to 10 or larger when trailer is equipped with brakes. 30 amps is far more than a trickle and about the max that alternator will apply in this wiring configuration. Replacing 10 gauge with 2 gauge "might"result in a 0.x increase in charging amps. 2 guage wiring from truck batteries to trailer battery will certainly supply a large amp reserve while pump is running but if that reserve is used will discharge truck batteries as above. I suggest anyone having problems with dying battery A make certain battery is good B make sure ground and battery wire connections are clean and tight throughout. If folks don't take anything else I say serious they might want to look close at this tip I haven't heard from anyone.
Run ground from truck side 7 way (4 way also) to a brass stud brazed to truck frame. A SS silver brazed works also. Splice into trailer side ground and do the same on trailer if brakes are grounded to frame. Redundancy is also a good idea here. Either fuse battery wire and unplug while dumping or have it on auto relay to disconnect while dumping. Another free tip I haven't heard yet. Since this fuse is critical and knowing if it has blown is important, wire a small lamp across fuse. When fuse blows lamp will glow signaling need to replace. Now go haul rock before weather turn's bad.

 

[LD1]

Ld1 and Woody,I didn't ask how the OEM system works,I said I don't see this modification improving on the OEM. The hardwired I referenced is that in LD1's example. Thank both you for all the words explaining how this works but I'm afraid there's flaws in you reasoning. I don't care to undertake breaking all of this down but will point out a fairly simple point for each of you. LD1 those truck batteries aren't loafing along just for the ride,to start the diesel engine they need to be at or near 100% full charge any time truck is started. If a dedicated trailer battery is discharged over a period of X ,the 2 truck batteries will 50% discharge over the same period (2 batteries shouldering the job of 3).
Woody,the 10 guage wire commonly used for battery and ground in 7 way is capable of 30 amps continuous and 40 amps interment. If 7 way has 12 guage at those positions,it's reccomend upgrading to 10 or larger when trailer is equipped with brakes. 30 amps is far more than a trickle and about the max that alternator will apply in this wiring configuration. Replacing 10 gauge with 2 gauge "might"result in a 0.x increase in charging amps. 2 guage wiring from truck batteries to trailer battery will certainly supply a large amp reserve while pump is running but if that reserve is used will discharge truck batteries as above. I suggest anyone having problems with dying battery A make certain battery is good B make sure ground and battery wire connections are clean and tight throughout. If folks don't take anything else I say serious they might want to look close at this tip I haven't heard from anyone.
Run ground from truck side 7 way (4 way also) to a brass stud brazed to truck frame. A SS silver brazed works also. Splice into trailer side ground and do the same on trailer if brakes are grounded to frame. Redundancy is also a good idea here. Either fuse battery wire and unplug while dumping or have it on auto relay to disconnect while dumping. Another free tip I haven't heard yet. Since this fuse is critical and knowing if it has blown is important, wire a small lamp across fuse. When fuse blows lamp will glow signaling need to replace. Now go haul rock before weather turn's bad.

Sounds like you didnt understand what I said at all.

Hardwiring with 2-ga is NOT making 2 batteries now do the work of 3. ITs making 2 batteries (WITH A RUNNING TRUCK AND ALTERNATOR) do the work of the SINGLE battery in the dump trailer. Because a dump trailer is disconnected (either manually or automatically) when the dump trailer is dumping. So you are ONLY using the deep cycle battery and the truck batteries are not in play.

You also seem to not understand voltage drop, and how battery charging works.

It isnt just the amps, but its the voltage. You can have 100amps available at 12.4v and it aint gonna charge a batter very fast.

Aside from needing a battery for breakaway protection.......with a 2ga hardwired setup you DONT EVEN NEED THE BATTERY IN THE TRAILER. It becomes EXACTLY how they do 1-ton dump truck power packs.

Again, the trailer ONLY has a battery so it can be a complete stand-alone system and can be towed by ANY vehicle.

With voltage drop.....all a truck can do is at best a trickle charge. Dont care what you say or what you think. THOUSANDS of people with dump trailers know that if they make short trips, the trailer battery dont have time to recover.

Maybe all of this is simply a difference of real world experience vs what should happen in "theory"??