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Alternator

My leese Neville 160 alternator was rebuilt last year. At the alternator it's 15.5 V, through the isolator it's 14.7-8 volts, so the isolator is working correctly. The only regulator I can seem to find is set at 14.2. Which is to low. Does anyone have an idea on an adjustable regulator? 13.8 coming out of the isolator would be great, 14.5/6 at the back of the alternator. I don't actually think the 14.8 will hurt my new AGM house batterys, but I'd really like to calm it down a bit.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #1 –
My opinion only:  I think "13.8 coming out of the isolator" is too low.

Does your alternator have a sense wire terminal?

If yes, is the sense wire connected to start battery POS terminal?

If yes, then alternator should automatically adjust itself to compensate for the voltage drop through the isolator.

You would like the voltage measured at start battery to be around 14.2 when alternator is running at idle.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Alternator

Reply #2 –
Chuck, 14.4 at the house at idle, 14.8 on the Silverleaf at all times. Need to check the start batteries at idle. The sense wire is connected to the pos side of the start battery. I wouldn't mind a 13.8 volt. I have an automatic charge control relay, so my solar is going to take care of topping things off. I'm considering taking the alternator out of the house system, as I can always use the boost if necessary to charge the house. The solar seems to do a much better job charging the 3 8d AGMs.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #3 –
Bruce, doesn't your alternator have the voltage adjustment screw? My factory Leese Neville 160 amp has one.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Alternator

Reply #4 –
Quote from: craneman –
Bruce, doesn't your alternator have the voltage adjustment screw? My factory Leese Neville 160 amp has one.
no it doesn't, in searching the internet it seem they are no longer available. Before the rebuild the old one was adjustable. My fault though for having them replace it along with everything else.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #6 –
Thanks Mike, I now have a back-up.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Alternator

Reply #7 –
Thanks Mike, I'll see if I can find somewhere to ship it to.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #8 –
Leese Neville alternators have had 3 choices of voltage regulator: variable with small screwdriver (not common), fixed voltage (never seen one), and the most popular has three internal jumpers that can choose between voltages (open up to change jumpers).

Re: Alternator

Reply #9 –
Barry, can you send me the part number for the 3 voltage regulator?
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #10 –
I put a Balmar external regulator on my coach so I can set the three stages any way I
want and it has a heat sensor on the alternator so I can't burn up the alternator. There
is also a place to put a heat sensor on the batteries but my batteries will take a lot more
heat than I get from charging.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Alternator

Reply #12 –
My  leese Neville 160 alternator has the 3 set point regulator, for Lo, Medium, or Hi voltage settings. I found it was difficult to know from the diagram what the actual setting was, so be sure to measure the voltage after changing the setting. I believe the voltage settings are 13.8v, 14.2v, or 14.6. I used an analogue voltmeter at the dash so voltage could be monitored while driving. My target for the AGM batteries was 14.4 volt. With regulator set to 14.2v, I added a standard 5 watt resister to the sense wire which raised the voltage at the batteries to 14.4v. while the alternator was still sensing 14.2v

Note that I moved all the wires on the metal plate behind the driver side rear tires to under the foot of the bed, so adding a resistor to the sense circuit was easy.   
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: Alternator

Reply #13 –
Am I missing something here? If the voltage regulator is set to 14.2, how can the resistor make it kick the voltage up? Is the voltage regulator capable of increasing the voltage above the set point.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #14 –
Quote from: bbeane –
Am I missing something here? If the voltage regulator is set to 14.2, how can the resistor make it kick the voltage up? Is the voltage regulator capable of increasing the voltage above the set point.
The resister makes the voltage regulator put out 14.4 thinking that it is reading 14.2
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Alternator

Reply #15 –
After doing a little investigation, actual voltage is 15.4 at the alternator, 14.2 at both battery banks. I adjusted the voltage on the Silverleaf to reflect the proper reading.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #16 –
How do I adjust the Silver Leaf to have it tell me the actual voltage.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Alternator

Reply #17 –
Quote from: oldguy –
How do I adjust the Silver Leaf to have it tell me the actual voltage.
Govto advanced at the top, then to engine corrections click on what you want to correct, look for multiplier adjustment adjust accordingly, careful a little goes a long way.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Alternator

Reply #18 –
Thanks Bruce got my son out to the coach and he got the voltage set right on the Silver Leaf
and I used a voltmeter to check the dash voltmeter and it is out also.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Alternator

Reply #19 –
 *potential dumb question(s)*
 I also have a Leese Neville and for some reason the PO disconnected the smaller wires to it.
 It was stated that the "sense" wire goes to the start battery + terminal.

1) does that cause the alternator to generate power and provide current back to the battery?
1a) isn't that the same as the large wire going between the alternator and battery?
1b) theoretically, I could jump from the alternator start battery + terminal to the sense terminal and have current produced?

2) on a TEMPORARY basis could I do 1b above and turn on the "boost" switch to charge the house battery bank?
In restless dreams I walked alone.
Narrow streets of cobblestone.


'93 U225
Build 4337
'14 CRV Toad

Re: Alternator

Reply #20 –
Quote from: Moby –
It was stated that the "sense" wire goes to the start battery + terminal.
1) does that cause the alternator to generate power and provide current back to the battery?
1a) isn't that the same as the large wire going between the alternator and battery?
1b) theoretically, I could jump from the alternator start battery + terminal to the sense terminal and have current produced?
2) on a TEMPORARY basis could I do 1b above and turn on the "boost" switch to charge the house battery bank?
1)  No.  You are confusing the SENSE wire with the EXCITE wire.  The SENSE wire tells the alternator regulator the voltage at the START battery.  The EXCITE wire (if required by your alternator) activates the alternator to generate power.  The SENSE wire is HOT all the time.  The EXCITE wire is HOT only when the ignition switch is in the ON position.

1a)  The voltage on the SENSE wire would be the same as the voltage on the large wire going between alternator and battery ONLY if the alternator is connected directly to the START battery.  In other words, if you didn't have a battery isolator in your charging setup.

1b)  As explained above, the SENSE wire does not activate the alternator.  This is the function of the EXCITE wire (if one is required).  Some alternators are "Self Exciting" and do not require the EXCITE wire.

2)  IF the alternator is connected directly to the START battery, and IF the alternator is putting out charging current, then activating the BOOST switch will allow the alternator to also charge the house batteries.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Alternator

Reply #21 –
Quote from: Chuck & Jeannie –
In other words, if you didn't have a battery isolator in your charging setup.

 So, that means because I have a boost switch, I have a battery isolator?
 Can I tap into any HOT when ON (of sufficient guage) line?
 Find the start battery on the isolator, run a line from that to the excite and I should be good?

 Sorry for all the questions, I've never been good with vehicle electrical systems.
In restless dreams I walked alone.
Narrow streets of cobblestone.


'93 U225
Build 4337
'14 CRV Toad

Re: Alternator

Reply #22 –
Quote from: Moby –
1.  So, that means because I have a boost switch, I have a battery isolator?
2. Can I tap into any HOT when ON (of sufficient guage) line?
3. Find the start battery on the isolator, run a line from that to the excite and I should be good?
1.  Not necessarily.  You can have a boost switch with or without a isolator.

2.  If asking about the EXCITE wire, yes, any source that is hot only with ignition switch in ON position will work.

3.  NO, that line would be hot all the time.  The EXCITE wire is only hot when ignition switch is in the ON position.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Alternator

Reply #23 –
Ok.
 1)  How do I tell if I have an isolator?
 3)  My bad, meant "sense".
      Sorry.

 Does it help to mention that my alternator has two charging lines coming out of it?
In restless dreams I walked alone.
Narrow streets of cobblestone.


'93 U225
Build 4337
'14 CRV Toad

Re: Alternator

Reply #24 –
One of the heavy wires will be positive the othe one will go to ground frame or engine.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country