Add me to the ODD battery voltage issue

Topic: Add me to the ODD battery voltage issue (Read 1298 times) previous topic - next topic

Re: Add me to the ODD battery voltage issue

Reply #25 – July 18, 2019, 08:30:15 am

Quote from: bigdog – July 17, 2019, 11:41:44 pm

So the sense wire tells the alt to increase voltage automatically to compensate for a diode loss and the opposite for a no loss isolator. I think I got that. Seeing all the posts about amps & voltage requirements had me scratching my melon.

CORRECT!

Re: Add me to the ODD battery voltage issue

Reply #26 – July 18, 2019, 10:51:19 am

Quote from: Caflashbob – July 18, 2019, 12:32:04 am

The batteries will only take so much input. Regardless of the alternator size. The LN has an adjustable voltage regulator on the unit.
See the eBay link on the deal on new ones. Look at the users. Gillig. Transit busses.
Std Delco puts our 14.15 volts to the battery as far a I have read, if the batteries are physically hot you are massively overcharging them. More than a volt. Ballooned cases.
As Brett has posted many times here you need 13,6 at the batteries to lessen the overcharge.

Bob,

All alternators will put around 14.4 volts (or a little more) or so when you start the car/coach tapering off as the battery voltage rises. The further the battery has been depleted during the night, the longer the alternator will produce the higher voltage. If you have voltmeters in front of on the dash, you can watch this happen. Batteries can take a very high charging rate until the temperature reaches 125 degrees. Our solar controller like many battery chargers, has a sensor glued to the side of the battery so if the battery temperature reaches 125 degrees, the voltage (like water pressure) will be reduced so the battery will not be damaged.

Radios, ECUs, etc are usually designed to operate at 13.8 volts.

Alternators will have an idle output and a 6000 RPM (alternator) output. The alternator fan is not that efficient at idle RPM and having to output it's max output for idle RPM on a hot day in a hot engine compartment can shorten it's life. In hot SoCal days and heavy traffic, the alternator earns it's keep plus car manufactures keep the pulley size small so the RPM is high to offset the heavy load the AC, etc put on it.

If you drive with the inverter on, heater fan on, lights, etc., don't expect to see voltages down in the low 13V range.

Yes, the voltage on a LN is adjustable but only with fully charged batteries and nothing else drawing current, should it be checked
with the thought of adjusting it.

Now, with automatic tensioners, the correct tension is kept on the belt. With no auto tensioner, the highest rate of alternator failure is with conventional belts being too tight and shortening the life of the bearings. The belt should just be able to be turned 90 degrees with your fingers half way between pulleys. Too loose, the belt slips, overheats and has a short life.

Pierce

Re: Add me to the ODD battery voltage issue

Reply #27 – July 18, 2019, 01:28:46 pm

Well, That trip to NAPA bore no fruit at all. In fact I was kind of miffed that they told me over the phone that YES their fancy hand held could check diodes while alt was on the engine. Which of course turned out to not be the case. They simply hooked up to my battery cable and said. 12.4V your OK. Brought out multi-meter and read 4.V at the iso center post. NOT OK.

I'm convince now that it is my alt. As the strong aroma of toasted electrical equipment was emanating from the alternator.

So now, Next question. Can I remove the belt from the alt. and run the genset on charge mode with boost on to get to my storage location? Walla Walla has a 24 hr limit for parking RV's, Boats and any sort of trailer at the curb.

Re: Add me to the ODD battery voltage issue

Reply #28 – July 18, 2019, 01:56:02 pm

Quote from: bigdog – July 18, 2019, 01:28:46 pm

. Can I remove the belt from the alt. and run the genset on charge mode with boost on to get to my storage location?

The short answer, Yes.

Mike

Re: Add me to the ODD battery voltage issue

Reply #29 – July 18, 2019, 02:10:31 pm

Quote from: Pamela & Mike – July 18, 2019, 01:56:02 pm

The short answer, Yes.

Mike

I like short answers. I thought that was the case. But feel better with a verification. Thanks Mike

Re: Add me to the ODD battery voltage issue

Reply #30 – July 18, 2019, 11:50:16 pm

Those are remote sense capable. If hooked up the alternator will adjust its voltage output higher until the voltage at the battery is 14 volts.

Here's the LN

Applications
Popular RV Motorhome Alternator
CUSTOM CHASSIS INC EL-039
DAIMLER TRUCKS NORTH AMERICA LN 2824LC
GILLIG CORP 51-00179-008
INTERNATIONAL TRUCK & ENGINE ZLN2824LC
LEECE NEVILLE 2824LC, 90772, A001090772, A0012824LC, A0012825LC, 2825LC
MACK TRUCKS INC 2742 5034-2824LC,
Monaco A001090772, A0012824LC, A0012825LC
Newmar 2824LC 2825LC 2828LC
OSHKOSH CORPORATION 6HA518
PRINOTH 110954522
SPARTAN MOTORS INC 0499-GG1
VOLVO NORTH AMERICAN CORP. LN 2824LC

Series number: 2500JB, 2600JB, 2700JB, and 2800JB.
MODELS: 2524JB, 2624JB, 2724JB 2824JB AND 2829JB

NOTE: INCLUDES STANDARD 8 GROOVE PULLEY

OEM(s): Leece Neville
System voltage: 12
Output: 160 AMPS
Rectifier location: Internal
Excitation type: Ignition Excite
Regulator Location: Internal
Mounting style: J-180
Fan Location: External
Rotation: BI-DIRECTIONAL
Mounting bolt size: 1/2-13 UNC
Positive stud: 5/16-18 UNC
Negative stud: 5/16-18 UNC

For Duvac or Dual Battery Systems
Industrial, Recreational & Medium & Heavy Duty Truck Applications
Weight: 24 lbs. / 10.91 kg

Includes Simple Hook-up Instructions

*PLEASE VERIFY YOU HAVE DUVAC TYPE SYSTEM BEFORE PURCHASE*

Re: Add me to the ODD battery voltage issue

Reply #31 – July 19, 2019, 10:35:00 am

Quote

So now, Next question. Can I remove the belt from the alt. and run the genset on charge mode with boost on to get to my storage location? Walla Walla has a 24 hr limit for parking RV's, Boats and any sort of trailer at the curb.

On my u-240, running the genset gets you 110vac and onboard 75 Amp battery charger. Now you can run anything that uses 110vac like A/C's to stay cool on the way and still run the 75 amp battery charger. Turn off all 12vdc items like Headlights, radio, cb. Boost switch must be ON for charging starting/chassis batteries from house/onboard charger. Why remove any belt that is running good? Go far it I think you will run as long as genset is running.

Re: Add me to the ODD battery voltage issue

Reply #32 – July 19, 2019, 12:43:49 pm

Once you make sure a start battery is not internally shorted, the generator besides supplying the battery charger for the start batteries will not only run the main engine forever, but also both ACs, inverter, microwave, headlights, etc. until it runs out of fuel. How much juice do you think it takes to run the ECU, etc? Not much. You don't even need the boost solenoid.

Pierce

Re: Add me to the ODD battery voltage issue

Reply #33 – July 19, 2019, 12:50:28 pm

Quote from: Pierce & Gaylie Stewart – July 19, 2019, 12:43:49 pm

You don't even need the boost solenoid.

Pierce

MAYBE. But not if wiring is OE. From the factory, the inverter/charger or converter ONLY charge the house bank, not the chassis battery.

So, boost switch needed. OR as an alternative that takes 5 minutes to do, hard wire the battery banks together-- easiest at the battery isolator. Just remove the cable from one outer lug (goes to one battery bank) and ADD IT to the other outer lug (goes to the other battery bank. Basically makes one large bank. Make sure you do not have any weak batteries that could affect all the other ones. If one is weak, remove or replace it.

No problem with driving as far as you want like this-- just mind "total bank" voltage if drycamping!!!

Re: Add me to the ODD battery voltage issue

Reply #34 – July 19, 2019, 12:54:31 pm

Quote from: Pierce & Gaylie Stewart – July 19, 2019, 12:43:49 pm

Once you make sure a start battery is not internally shorted, the generator besides supplying the battery charger for the start batteries will not only run the main engine forever, but also both ACs, inverter, microwave, headlights, etc. until it runs out of fuel. How much juice do you think it takes to run the ECU, etc? Not much. You don't even need the boost solenoid.

Pierce

because after arriving at napa for an alt test. I could smell burning electronics coming from the alternator. So I thought it best not to push it into catching fire driving on the highway to my storage location. The coach is now at it's storage location.

Re: Add me to the ODD battery voltage issue

Reply #35 – July 19, 2019, 12:56:01 pm

Your incident brought up maybe another advantage to a auto combiner.

If the alternator was to fail our house battery side which in daylight is being charged while driving as it's hooked up thru the refer wires then to the combiner then to the house system would have combined the batteries and charged the engine batteries from the solar.

Not unusual except for the automatic part if the driver did not notice the failure.

I keep dual 12.00 volt gauges in the dash while driving and under discharge they show warning lights.

Versus a 3amp consuming 12v boost switch that manually needs to be energized and no power loss auto system would seem a better way?

In my case if the systems load exceeded my solars output or at night then the auto combiner would disconnect the banks and the engine battery dash display would show lower volts right away and it's warning lights display

Re: Add me to the ODD battery voltage issue

Reply #36 – July 19, 2019, 01:15:22 pm

I have decided to order up a new Delco-Remy 28si 180amp alt, Sterling zero loss isolator. And a new AC belt tensioner that broke in half.
Found the alt. at find it parts for $315.25

and the Sterling Iso at Bay Marine. And always helpful MoT had the AC pulley and bracket in stock.

Re: Add me to the ODD battery voltage issue

Reply #37 – July 19, 2019, 02:19:25 pm

Good info pierce.

On startup I see around 13.85 volts max. Probably because the auto combiner has both banks together as soon as the alternator is energized by exceeding normal idle.

I notice the new LN has a updated solid state internal voltage regulator that supposedly energizes the alternator to start at lower levels.

A sensing alternator that adjusts it output to always be 14 at the engines battery bank would seem to need optima red tops which were made to handle the high battery heat and higher voltage.

If the no loss isolator and the Delco end up putting out 14 volts always to both banks the house side at minimum in summer is being at least .75 volts overcharged.

In a non sense system you could add load to reduce the volts. In a sense system if hooked up the alternator turns itself up.

The LN has large heat sinks and a large external fan to cool it at high under hood temps and low rpms as far as I know.

Hence the use by Gillig as they built the Gillig Phantom intracity transit busses for many years.

I would test this and after the batteries are fully charged the Delco is still putting out 14volts I would disconnect the sense wire.

Their Delco site shows 13.5 without the sense. As 13.6 was the voltage for long drives that would slow the overcharging damage.

Factory used the LN and mk gels and redtops as this combo lasted longer. Lots of 10-12 lives reported here for this exact setup.

House side charging on inverter for the last 20 years has been temp controlled.

But not the alternator unless you had a link 2000R panel on a old freedom 25 for the engine side.

Too much work and parts when redtops handle the overcharge and heat when they moved the batteries into the engine bay when the unicoach was built in 95.

Temp controlled engine battery charging had the alternator down to almost 13 volts. Buddy had to disconnect the engine batteries temp sensor

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Re: Add me to the ODD battery voltage issue

Reply #25 – July 18, 2019, 08:30:15 am

Re: Add me to the ODD battery voltage issue

Reply #26 – July 18, 2019, 10:51:19 am

Re: Add me to the ODD battery voltage issue

Reply #27 – July 18, 2019, 01:28:46 pm

Re: Add me to the ODD battery voltage issue

Reply #28 – July 18, 2019, 01:56:02 pm

Re: Add me to the ODD battery voltage issue

Reply #29 – July 18, 2019, 02:10:31 pm

Re: Add me to the ODD battery voltage issue

Reply #30 – July 18, 2019, 11:50:16 pm

Re: Add me to the ODD battery voltage issue

Reply #31 – July 19, 2019, 10:35:00 am

Re: Add me to the ODD battery voltage issue

Reply #32 – July 19, 2019, 12:43:49 pm

Re: Add me to the ODD battery voltage issue

Reply #33 – July 19, 2019, 12:50:28 pm

Re: Add me to the ODD battery voltage issue

Reply #34 – July 19, 2019, 12:54:31 pm

Re: Add me to the ODD battery voltage issue

Reply #35 – July 19, 2019, 12:56:01 pm

Re: Add me to the ODD battery voltage issue

Reply #36 – July 19, 2019, 01:15:22 pm

Re: Add me to the ODD battery voltage issue

Reply #37 – July 19, 2019, 02:19:25 pm

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