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Topic: isolator (Read 1259 times) previous topic - next topic

Re: isolator

Reply #25
Check the number of pins on the relay before you order new ones.  Just pull the wiring connector off and count the pins.  "Bosch style" relays come in 4-pin and 5-pin versions.

The link I provided above for the relays is the 5-pin version, and they are not genuine Bosch brand.  However, they have worked fine on our coach for many years.

I bought the 10 pack because I also use those type relays in other projects.

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: isolator

Reply #26
So I guess the question is have you done any of this or just ready to remove the alternator?
New isolator?
Cleaned and verified starter cables?
Replaced circuit breakers?
Replaced wire ring lugs on CB?
Verified voltage on sense wire?
Ohmed out all your cables and grounds?
This would be the foundation to a good repair before removing alternator for repair for me

Re: isolator

Reply #27
Alternator has been tested good, I'm about to replace my isolator with a Victron Argofet along with cleaning connections and replacing the solenoids, breakers and relays. While at FOT IN '21 @ the GV reunion, they replaced my alternator and also installed a BEP DVSR to my isolator, do I need to attach that to the new Victron isolator? Thanks again for all the great help here!
Michael & Roxene, Aussie the wonder dog & his daughter Luna the lunatic.
1993 Grand Villa Unihome 280 build #4203
36' 8.3 Cummins 300 hp- 2001 Chevrolet Tracker toad

Re: isolator

Reply #28
I am not sure how that is supposed to work, but from what I see, doesn't that take the place of the isolator. If it charges the battery through a relay I would think that it would be keeping the batteries isolated. Like I said, not familiar with that system.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: isolator

Reply #29
Ron,
That's what I was thinking, I thought it would be redundant to have it. They might have installed it because I was having charging issues.
Michael & Roxene, Aussie the wonder dog & his daughter Luna the lunatic.
1993 Grand Villa Unihome 280 build #4203
36' 8.3 Cummins 300 hp- 2001 Chevrolet Tracker toad

Re: isolator

Reply #30
NO, it takes the place of the old-style diode-based isolator.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: isolator

Reply #31
So with that, he shouldn't need an isolator. Maybe that is what has been causing the no charging issue.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: isolator

Reply #32
Wire the Victron Argofet properly and remove the old-generation battery isolator.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: isolator

Reply #33
Mike said  "they replaced my alternator and also installed a BEP DVSR to my isolator".

Not being familiar with a BEP DSVR, would it be tossed along with the old isolator?
Frank & Connie Williams
1999 U320 '36
Build: 5466
MC: 18335

Re: isolator

Reply #34
Not being familiar with a BEP DSVR...
Digital Voltage Sensing Relay (DVSR) 12/24V

IMO, either use the ArgoFET isolator, OR, use the  BEP DVSR.  One or the other - not both. 
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: isolator

Reply #37
If you go with the Victron Argofet isolator, you may need to turn the voltage output down in the alternator. At the alternator mine is 15.1 one the out put side of the diode isolator it's 14.3-14.4 volts
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: isolator

Reply #38
If you go with the Victron Argofet isolator, you may need to turn the voltage output down in the alternator. At the alternator mine is 15.1 one the out put side of the diode isolator it's 14.3-14.4 volts

I am surprised that the sense wire doesn't take care of the automatically, since its job it to provide the correct voltage at the chassis battery bank.

Said another way, if the system does not experience the .7 VDC drop across a diode-based isolator, it should merely communicate the 14.3 VDC to the alternator.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: isolator

Reply #39
It may, that's the way it's SUPPOSED to work.
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: isolator

Reply #40
It may, that's the way it's SUPPOSED to work.

Yes, if it doesn't, a good idea to verify that the sense wire connections are clean and tight.  A little resistance can cause the alternator end of the sense wire to read lower than actual and lead to high voltage output.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: isolator

Reply #41
just wanted to follow up with the replacement of isolator and alternator issues. Long story short, replaced isolator with the Victron Argofet, replaced old boost and starter solenoids, replaced old, worn resettable breakers and relay. Finally found the problem wire for the alternator- ignition sense wire was hooked to the wrong wire, once that was identified, everything is working. I deeply appreciate all who gave me advice and help. It was a great feeling to get my batteries charging again. Special shoutout to Red Tractor who took many frustrated phone calls from me.
Michael & Roxene, Aussie the wonder dog & his daughter Luna the lunatic.
1993 Grand Villa Unihome 280 build #4203
36' 8.3 Cummins 300 hp- 2001 Chevrolet Tracker toad

Re: isolator

Reply #42
Finally found the problem wire for the alternator- ignition sense wire was hooked to the wrong wire, once that was identified, everything is working.

FYI the SENSE terminal is connected directly to the chassis battery side of the battery isolator.

The IGN terminal is connected to some "only hot when ignition on" source.

They provide two very different but necessary functions.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: isolator

Reply #43
While at FOT IN '21 @ the GV reunion, they replaced my alternator and also installed a BEP DVSR to my isolator, do I need to attach that to the new Victron isolator?
I seem to remember reading that FOT installs a BEP DVSR to function as a Trik-L-Start to charge the chassis battery while on shore power.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

 

Re: isolator

Reply #44
I seem to remember reading that FOT installs a BEP DVSR to function as a Trik-L-Start to charge the chassis battery while on shore power.

The BEP DVSR, like the Xantrex Echo Charger is one of the "smart thief" type devices to charge the chassis battery from the house battery bank when the house bank is being charged (voltage of 13.2 VDC or higher).

It is a reasonable alternative to a stand alone low amp smart charger.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020