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Topic: Where to Connect Engine Trickle Charger (Read 1030 times) previous topic - next topic

Where to Connect Engine Trickle Charger

Hi friends.  I've been searching and reading about trickle chargers for the engine batteries.  I've accessed the battery isolator by lifting the engine cover and I see the large gauge cable coming from the alternator and then two more cables from the isolator labeled Battery 1 and Battery 2.  My isolator is mounted to the front wall center of the engine compartment.  It appears to have only 3 lugs (don't see a sense wire mentioned in some posts).

I plan to attach the trickle charger using ring terminals for safety and security. 

My question is WHERE should I attach?  To the isolator?  To some other point?

Thanks!!

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Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Where to Connect Engine Trickle Charger

Reply #1
Mark,

I installed our trickle charger on the electrical bus panel, not the panel with the isolator. I plugged it in to the 110V right next to the bus panel and then went into the engine battery lug. When the 110V plug is hot, the engine batteries charge. There are three lugs  to choose from, two for house batteries and one for the engine battery. The panel with the isolator is under the coach and gets a lot of moisture and was not as convenient. Different years and models will have different locations.

Your schematic will show the bus panel. Good time to take the schematic to the print shop to have it blown up to max size to make reading it easy. Cheap and then roll it up in a mailing tube. I can also send a photo of ours or see our old post.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Where to Connect Engine Trickle Charger

Reply #2
If I remember correctly I attached mine to each side of the boost solenoid and mounted the charger inside the
compartment at the foot of the bed, where the breaker boxes are located.  Rather than drill a hole for the wires I removed a screw
from one of the washers that hold the insulation on that wall of the engine compartment, enlarged the hole a bit, ran the wires
and siliconed the hole up.  The screw and washer weren't really supporting anything as they were real close to the mounting panel for the isolator, etc., so I merely used silicone to hold the washer, for esthetics.

Re: Where to Connect Engine Trickle Charger

Reply #3
So Mark, are you talking about a stand alone 110 powered battery charger or something like a Trick l Start chassis battery maintainer?

Steve
Steve & Sandy
2003 U320 4220 WCDS, build#6160
Motorcade #17794
USMC '67-'71

Re: Where to Connect Engine Trickle Charger

Reply #4
Steve - A 4-stage trickle charger, battery maintainer.  It will be active whenever 120VAC is present at the receptacle, i.e., whenever shore power is connected or the genny is on.  There's a link to the unit in my original post if you'd like to see it.

Mark
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Where to Connect Engine Trickle Charger

Reply #5
I installed our trickle charger on the electrical bus panel, not the panel with the isolator. I plugged it in to the 110V right next to the bus panel and then went into the engine battery lug.

Is the bus panel in the electrical bay?
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Where to Connect Engine Trickle Charger

Reply #6
Mark, my bad for not reading your post carefully. I understand what you want to do but think that using a Trick L Start or the Xantrex Echo Charge would be a better way to go as there is less complexity involved. Just my opinion FWIW.

Steve
Steve & Sandy
2003 U320 4220 WCDS, build#6160
Motorcade #17794
USMC '67-'71

Re: Where to Connect Engine Trickle Charger

Reply #7
If I remember correctly I attached mine to the chassis battery side of the boost solenoid and mounted the charger inside the
compartment at the foot of the bed, where the breaker boxes are located.

We used a battery combiner (when charging only) rather than a utility line trickle charger - but we also used this area: foot of the bed and either side of the boost solenoid.  It's a convenient location with excess space and access to all applicable lines for either charging method.
James
w/ DW Erin, sons Gideon and Tobias, cats Oscar & Oliver
Fulltime 1999 U270 34' #5508

Re: Where to Connect Engine Trickle Charger

Reply #8
Is the bus panel in the electrical bay?
Our bus panel is just forward of the wet bay but may be be different as I said in different models. It has a plastic cover on it held in place by two nuts/washers. I replaced the nuts/washers with stainless when I installed the solar. You just have to make sure you attach it to the engine battery lug, not the coach lug.

I have attached two photos, one of the trickle charger next to the converter and water tank. The other shows the bus panel. The converter's fan is visible in both photos. You can see where I brought the cable in from the solar controller to the coach batteries at the bottom left. I put a 250 amp fusible link to protect the coach/solar on the controller side of the bus. The trickle charger installs in just several minutes and I never really look at it. Good grounding point about 3 inches from the fan. You can see the bright copper cable lug with the black shrink wrap on it in the right bottom of the photo. I just monitor the dash digital voltmeters to make sure the engine batteries are at about 13V while on shore power. All batteries are about 8 years old and happy.
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Where to Connect Engine Trickle Charger

Reply #9
Mark, my bad for not reading your post carefully. I understand what you want to do but think that using a Trick L Start or the Xantrex Echo Charge would be a better way to go as there is less complexity involved. Just my opinion FWIW.

Steve
Steve,

I'll study both of these options tonight.  The only reason I headed in the Battery Tender direction is that it's a known entity to me.  Keep one on my riding mower and in the past on several old Mercedes's that I rarely drove.  Always open to better options!  Thanks for the info.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971



Re: Where to Connect Engine Trickle Charger

Reply #12
http://lslproducts.net/TLSPage.html

What I use.

Mark
The selected media item is not currently available.
Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara

Re: Where to Connect Engine Trickle Charger

Reply #13
Thanks everyone.  3 terrific suggestions.  The Blue Sea Systems and Xantrax were both interesting options but in the end I liked the Trik-L-Start a little more. I cancelled the order for the 120VAC Battery Tender and ordered the Trik-L-Start.  Simple, elegant solution.

Appreciate it.  Mark
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Where to Connect Engine Trickle Charger

Reply #14
You'll like the Trik-L-Start. Real easy. Here's mine. I just had to lengthen the wires a bit to reach one of the terminals on the isolator.
jor

93 225
95 300
97 270
99 320

Re: Where to Connect Engine Trickle Charger

Reply #15
Mark
I used the 15 amp AMP-L-START but I mounted at the foot of the bed away from the engine bay heat.The bedspread covered the unit but I could just lift briefly to see the lights. If mounted in engine bay one must view it either by opening the bed cover or the rear engine door. The unit simply steals some charging current from whatever source is feeding the isolator and when starting batteries are fully charged it went to a float voltage. The use of the battery boost switch became just a never used backup  at this point.
Every day is a gift
Bob and Pat
2000 36 U295 cummins 350hp
Coach has been sold thanks to MOT 11/2016

Re: Where to Connect Engine Trickle Charger

Reply #16
Mark
I used the 15 amp AMP-L-START...
Hmmm, I ordered the 5A model.  I can return it and get the 15A if that's the preferred option. 
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Where to Connect Engine Trickle Charger

Reply #17
I use the 15 A model but I think the 5 A would have been fine but as I boon dock in winter skiing I wanted to be sure.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Where to Connect Engine Trickle Charger

Reply #18
If your chassis battery load exceeds 5 amps while in storage/ignition off, there is another issue!
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: Where to Connect Engine Trickle Charger

Reply #19
The use of the battery boost switch became just a never used backup  at this point.

This is EXACTLY for what the boost switch is intended for.

Depending on how many start batteries you have, 5 amps should be more than enough. You don't really want to charge the batteries, just maintain the voltage at about 13 volts. The 15 amp may taper off to much less as the batteries reach float/maintenance voltage. Read the fine print before ordering. A check at the batteries with a digital voltmeter should tell you if it goes over about 13 volts. A constant 15 amps will cause a single 34 series battery to overheat and long term damage to a battery bank. Our trickle charger is 2 amps and keeps our three engine batteries at about 13.1 volts. They are about 8 years old and love it.

If you are dry camping and have solar, when the inverter is on and your trickle charger is plugged into an inverter hot outlet, the engine batteries will be kept at proper voltage. Absolutely no need to add a solar charger for the engine batteries. Just makes things more expensive and complicated.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Where to Connect Engine Trickle Charger

Reply #20
Pierce- you just brought up something that I am not sure of, so here is my question.

I have the Echo charger installed on my coach, which works while charging from shore power or generator.  I have solar installed that  directly charges my house batteries.  I am still using the isolator that came with my coach.  What you said above is that if I have my inverter/charger on while boon docking with solar, that it will charge my start batteries as well.  Do you know if that is so with the Echo charger?  I usually have the inverter off unless I am using it, maybe I should change that??

Thanks for your advice.      ^.^d
Ted & Karen
2001 U270 36' - sold after 12 years full timing

Re: Where to Connect Engine Trickle Charger

Reply #21
Pierce- you just brought up something that I am not sure of, so here is my question.

I have the Echo charger installed on my coach, which works while charging from shore power or generator.  I have solar installed that  directly charges my house batteries.  I am still using the isolator that came with my coach.  What you said above is that if I have my inverter/charger on while boon docking with solar, that it will charge my start batteries as well.  Do you know if that is so with the Echo charger?  I usually have the inverter off unless I am using it, maybe I should change that??

Thanks for your advice.      ^.^d
I don't know about the Echo charger. The parasitic draw on the engine batteries is very low and boon docking for several days should not see much of a voltage drop on the engine batteries unless you use the dash radio and other devices connected to the engine solenoid hot lug under the flip up dash. The time that your inverter is on should keep the engine batteries up from the 2 amp trickle charger. We usually watch TV at night for a couple of hours and then have the inverter on in the morning for the microwave, latte maker and TV. This is plenty of time for the trickle charger to keep the engine batteries up.

OK, a sure way but not recommended way is to just go into the electrical bus panel and connect a three inch wire from the coach batteries lug to the engine battery lugs. The wire can be a small gauge and you could just put a switch on it. You would want to make a dash sign so you remember to turn it off or remove it before heading out from your dry camping location. I did this for a year or so before installing the trickle charger. We have house AGM and engine conventional batteries but this was not a factor. Again, a sign for the wire and bat antenna are necessary. My neighbor tore his bat antenna off TWICE in a year and still didn't make a sign.

Instead of thinking about the engine batteries, install a digital dash voltmeters or plug in voltmeter to keep an eye on both batteries, both while dry camping and also while driving. You can tap into to Audit wires for both voltages or come off the lighter plugs on the dash and HWH panels.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Where to Connect Engine Trickle Charger

Reply #22
I connected mine directly to the batteries.  Keept it simple so it could be trouble shot later.

Keith
Keith, Joyce & Smokey the Australian Cattle Dog
1995 U320 SE Extreme 40' WTBI Build # 4780, with a Honda CR-V hopefully still following behind.
Motorcade # 17030
FMCA # F422159

Re: Where to Connect Engine Trickle Charger

Reply #23
I connected mine directly to the batteries.  Keept it simple so it could be trouble shot later.
Keith
Perhaps the simplest and the best solution. For rear battery coaches, a 110V outlet could be installed next to the block heater outlet, the charger plugged in with the wires fed to the batteries. Shore power keeps everything happy and if the outlet is inverter hot, it keeps the batteries up while dry camping.
Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Where to Connect Engine Trickle Charger

Reply #24
Another fan of Trik l start. Installed at isolator with easy access to start batteries on my U270. Disconnect negative on house batteries when installing. Don't want an accidental grounding of wrench to chassis. Works for solar, land line or generator operation. Also very affordable.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.