Bench test of RENOGY 40A DC to DC Charger

Rbertalotto

Explorer
I finally got to test the RENOGY 40A DC to DC Charger on my truck and my portable battery.
Truck is a 2018 RAM 2500 / 6.4L Gas with 220A "smart" alternator
Battery is a AGM 100Ah in a portable battery box I made here ....


I ran a 15' / 6g wire from my winch connection connected directly to the trucks battery to the DC to DC Copnverter.

The RENOGY DC to DC Charger will be used in a couple different vehicles and in my boat so it was made portable with a couple Anderson high current connectors.

IMG_20200119_153042594.jpg

I didn't have the correct fuse for the pictured fuse block so for the test I simply jumped across it.

The Green wire is the switched lead to turn the unit on and will be connected to a switched 12V lead in the different vehicles when those vehicles are wired. (Notice, the RENOGY owners manual has a mistake. They say to connect this wire to the + battery or alternator terminal. If you do that the DC to DC charger stays on all the time and will drain your start battery if the vehicle is not running.)

So...From the trucks battery to the DC to DC Charger and then to the Aux battery......Pretty easy.

This Aux battery was at 98.1% so the amps it was requesting was minimal.

IMG_20200119_153105700.jpg

Only 4.06 Amps being sent to Aux battery

IMG_20200119_153056086_BURST000_COVER_TOP.jpg

Voltage from the trucks battery....Float Mode

IMG_20200119_153114217.jpg

Tomorrow I'll test it in my Toyota Venza to see how it works with that vehicle.

Once it is all installed in the vehicles I'll do a more complete write up.
 

john61ct

Adventurer
Please give feedback on these points, apparently their three DCDC models vary on some.

Not allowing user-custom adjustable setpoints, only a limited set of canned profiles.

Requires an external switch, really designed for Alt-only charging tied to IGN, no built-in auto voltage sensing relay.

No mention in writing of any IP water resistance rating.

Only warranty mentioned is the "statutory" minimum, great if you're in Australia, stateside not so much.

I'm hoping otherwise turns out to be very reliable, Renogy do have great CS attitude and a good reputation to uphold.
 

shade

Well-known member
No mention in writing of any IP water resistance rating.
It's a strange manual, that's for sure.


Page 12 of the manual (pg. 13 of the pdf) warns against dust, gas, and splash exposure, specifies a dry mounting location, and says to avoid hot locations - even direct sunlight. It then goes on to mention mounting behind a headlight or radiator, and repeats the warnings about dust, moisture, heat, etc.

Weird stuff. I'd only install one in a sheltered location.
 

Martinjmpr

Wiffleball Batter
Glad to see it's working. I have the 20a version and will also use it to charge up a battery-in-a-box like yours. I haven't installed mine, I still need to figure out how to get a pair of wires from the battery to the cab. Mine will sit under the back seat of the truck in the little storage tray.
 

jeffjeeptj

Adventurer
I have a 20A unit. I agree with canned profile potential problems. I am using my Battleborn (BB) as a test subject. The Renogy’s DIP switches 1 - 4 in On, DIP 5 in off. Version 1.1 of the Renogy Manual states using with LiFePO4 chemistry with internal BMS only. This gives me a bulk of 14.6V (just what BB wants). There is not a reduced absorb and the manual states there is no float when in LiFePO4 mode (DIP 5 off).
i have mounted the Renogy to the battery box which the BB is in, and place it behind the Driver’s seat. I have Anderson connectors for the trigger and the engine battery/alternator in. I have the trigger run to an ignition controlled cig lighter in my Sequoia. I have been on a 3 month traveling trip with my ARB fridge plugged into the BB. I control “overcharging” by unplugging the trigger wire from the cig lighter and letting the ARB run off the BB. I am only using a volt meter to monitor batt voltage along with “seat of the pants” charge/run duration. I have run two Anderson Powerpole connections, one with #10 and one with #16 gauge wire. I generally use the #16 for my G.T.Power volt meter I leave plugged in when driving. The #10 is for my ARB or connection between my Solar Charge Controller and the BB if I decide to charge the BB that way.

Not as automatic/user programmable as I would like, but, sufficient for the price. I would prefer to have a Sterling, but, I am retired now.

johnct61, I do not have good responses to your points/questions. Having been a saltwater boater for most of my life, I would not use the Renogy for any length of time on a boat. If I were to take my BB/Renogy package on a boat, I would keep it in a cabin, and take it home at the end of day. If I was to go on a cruise for more than a couple of days, the package would not go. I’ve seen to much stuff get corroded on a boat.

The package has worked sufficiently for my 3 month trip. Currently, it is out of the Sequoia, on my bench, charging via a 55A power supply through the Renogy. It doesn’t see rain, road dirt/dust, underhood temps, and has not yet failed. It does far better than the Renogy with an Odyssey Group 31. The Odyssey just did not want to charge. Of course, there is a lot of info on this site about the Odyssey Group 31/PC2150 being hard to charge.

One thing I just added (not in the photo) is an additional SB50 Anderson connector with #8 direct to the battery. Gives me the option of direct connection to my 14.6V/55A power supply for charging more quickly than the 20A Renogy.
 

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Rbertalotto

Explorer
Thanks for this info JeffJeep. Great write-up.
Today I ran my Renogy 40 DC to DC charger off my Toyota Venza to charge my Group 31 AMG battery box. The battery was at 80%. I was concerned about the Venza's alternator overheating as it sat there for 39 minutes idling and charging at 28 amps. Using a laser thermometer I started with the alternator at 50 degrees and after 15 minutes it was at 95 degrees. Other parts of the engine was at 130 to 150 degrees. 95 degrees doesn't concern me. I think using my car as a stationary charger when there is no sun will work out better than transporting a generator.
So far I'm very impressed with this device.
 

Bayou Boy

Adventurer
Just FYI, every single product I've found from Renogy was a rebadged generic chinese product with the other "brands" easily found on Amazon or Alibaba. It won't be long until the generic versions of this show up too.
That's why this product is as limited as you guys are finding out.

Also, the Redarc DC-DC charger is rated for wet locations. People install them on trailer tongues all the time. It's not really much more configurable though and significantly more expensive.

Edit Redarc is ratedfor wet conditions not Renogy. Brain fart.
 
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john61ct

Adventurer
Yes Renogy is a mass marketing & distribution outfit, not a technology company, likely design nothing manufacture nothing.

But they have been building a solid brand identity, thus have a stake in not going too far down the cheap-Chinese race to the bottom.

Their DCDC aren't the best but good enough for most it seems given the low pricing.

And so far customer service reports handling warranty issues etc have been consistently good.

Pretty well parallel to Battle Born IMO, long as you're aware of the limitations.
 

Bayou Boy

Adventurer
Yes Renogy is a mass marketing & distribution outfit, not a technology company, likely design nothing manufacture nothing.

But they have been building a solid brand identity, thus have a stake in not going too far down the cheap-Chinese race to the bottom.

Their DCDC aren't the best but good enough for most it seems given the low pricing.

And so far customer service reports handling warranty issues etc have been consistently good.

Pretty well parallel to Battle Born IMO, long as you're aware of the limitations.

Battle Born are at least assembled in the USA. Renogy is not.
 

Rbertalotto

Explorer
I just saw the 40A Renogy Dc to DC Charger went up in price $40! I bought mine recently for $159....now I see it at $199.....sometimes it pays to be an early adopter
 

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