Renogy Controller & Battery Install

[ski3pin]

A lot of options for battery systems in pop up camper have been well covered on this forum. Here's what I did in our ATC Bobcat. We have a smaller camper so it takes creativity to keep systems compact and light. A year ago I replaced our AGM battery with a Renogy lithium 100ah smart battery. I installed a Renogy 50A dual charge controller to maintain the battery. I build the camper in a side dinette style. The seats are also lids to storage underneath. The front seat has an angled seat back against the rear wall. I installed the dual charge controller behind the seat back.

My main camper power switch is on the left. The fuse box is auxiliary and for the two power points to the right (will be visible in a photo below). The main wires run below to the battery.

I installed new 6awg from the truck's engine bay to the camper and used 6awg for the short lengths between the controller and camper battery.

Below is the seat back in place along with the protection for the battery. In regard to heat generated by the controller. I have vent holes in the sides of the seat back support, the hole in the bottom front to view the indicator lights, and the top of the seat back support is open. In a year of use, I've not felt any heat from the unit.

Below is the hinged padded seat in place.

I works well for us and is compact.

 

[ckent323]

ski3pin,

Does the Renogy controller provide two different output charging voltages with each adjustable (programmable) for different battery chemistries?

 

[ski3pin]

Insofar as charging the camper battery, there are settings for the various types of battery (lead acid, AGM, lithium) along with the ability to customize a charging profile. Can this be done for charging the lead acid truck battery - after the camper lithium is fully charged? I have never looked. I use the lithium battery profile in the charge controller since I'm using a Renogy battery.

Here is a link to the manual - Renogy Dual Input

Did I hit what your question was?

 

[TacomaAustin]

@Craig

I recently installed the smaller 30 amp dual input Renogy charger - with the hope that it will never stress my 130 amp alternator. My ATC Bobcat is mounted on a 17 year old Toyota Tundra. I want the amperage draw to be limited.

Charging parameters: The first mention that Renogy gives with regards to the charging parameters of the lead acid starter battery is on page 6 - "Trickle charges the starting battery via solar panels if the service battery is fully charged." The service battery is the camper's house battery.

Over on page 13 - "If the service," a.k.a house "battery is in the float charge state, the starting battery will be charged at the same time. The charging voltage is limited to 13.8V. " On a lithium install there is no float cycle.

One thing to note, the charging of the vehicle's starting battery appears to be an intermittent on / off affair.

According to Renogy - "After charging the starting battery for 1 minute, it will disconnect for 30 seconds and check the starting vehicle voltage. - It will continue to charge the starting battery, if the voltage is lower than 12.7V and will stop charging if the voltage is higher than 13.2V."

So in my words, the charging voltage supplied to the truck's starting battery is 13.8V.

 

[TacomaAustin]

I installed a Renogy 50A dual charge controller to maintain the battery.

I works well for us and is compact.

A question for ski3pin - at the other end of the #6 gauge wire inside the engine bay, did you use a fuse or a breaker similar to what is mounted above your camper battery?

 

[ckent323]

Tacoma Austin, ski3pin, et al,

If the following is true then it seems to me it should be OK - It will continue to charge the starting battery, if the voltage is lower than 12.7V and will stop charging if the voltage is higher than 13.2V."

In this regard it apparently works similar to an ACR.
If it charges the AGM starting battery to 13.8 V and stays connected that may result in overcharging the AGM (depending on the manufacturer) and harm it. I think an AGM float voltage of 13.2 V to 13.5 V is safer (~2.25 V per cell) - but that is for my 6 V deep cycle AGMs. A 12 v starting AGM may tolerate up to 13.8 V.

There is some variation of the best charge voltage with temperature as well, increasing a couple of 1/10s of a V per cell for every 5 C drop in temp below 25 C and decreasing a couple of 1/10s of a V for every 5 C temp increase above 25 C.

 

[ski3pin]

A question for ski3pin - at the other end of the #6 gauge wire inside the engine bay, did you use a fuse or a breaker similar to what is mounted above your camper battery?

Yes, the same as the breaker at the camper battery. I believe I used the Will Prowse (?) video "how to" directions on the install.

Thanks to you both for the expertise on the charging of the truck battery. My approach has been much more seat of the pants. The truck battery hasn't shown any issues. There's been no sign of off gassing - wet battery top - and the starter immediately turns over.

 

[billharr]

Great use of space putting the controller in the seat back. Lithium is a game changer.

 

[TacomaAustin]

Yes - 3pin did a nice out of the way install that is compact and unobtrusive.

I built my panel as a 1 piece board outside of the camper and installed it about a month later. It ended up taking up more space, mainly to my preference for separate bus bars and placement of two resettable breaker within inches of the Renogy 30 amp dual input controller for short wire runs.

Here is the circuit panel before the install - note the lack of a 40 amp fuse between the controller's positive post and my positive busbar, which has since been resovled.

 

[TacomaAustin]

I also want mention that this particular Renogy controller draws 63 milliamps - while in standby. Therefore, it is handy to have a device to isolate the house battery from the controller for when the camper is indoor storage. .063 amps = about a 1.5 amp hours of parasitic loss per day. Over a 30 day period the parasitic loss will add up to a 45 amp hour drain.

 

[Defulmmt]

Heh Ski3pin,

I wanted to follow up on your experience with the Renogy controller. Are you satisfied with the performance and system design after several months of use? You mentioned in your review that you didn’t note much heat emission from the controller. What is the heat level when the unit is charging via the alternator? I’m planning an electrical system upgrade on my Panther and researched products from Renogy, Victron and Redarc. The Renogy appears to have a cost and simplicity advantage.

The Panther came with a Renogy solar controller, 160 watt solar panel and a 79 hour AGM battery. I added a Renogy bluetooth connection to the controller and a battery SOC monitor. I plan to upgrade to a dcdc charger and 100 amp hour Battleborn. I am inclined to just make this an all Renogy system but, then again, buy the best tool first and only cry once.

Any feedback on the Renogy system will be appreciated.

I think the WTW forums are great, in more ways than one. Thanks to all who make this such a useful resource.

 

[rubberlegs]

I had several nice chats with Mr. Ski3pin and also got the Renogy he used, but decided on the 30A unit. I figured it would get less hot, because the box and heat fins are the same as the 50A version as far as I can tell. The only convenient place to mount it was in the battery compartment on our side dinette camper. So I mounted it right over the two vent holes. I was pretty concerned about overheating inside the battery compartment. Lithium batteries don't need venting, so using the holes for cooling seemed reasonable.

Other reasons for the 30A dual-charge controller besides less heat: less stress on the alternator, charges the battery slower so maybe less stress on it (we generally drive for at least 30 minutes), possibly could have used 8 gauge wire instead of 6, but we did use 6 from truck battery to camper battery, and there's another reason but can't remember right now! It didn't cost much less than the 50A version though. That was disappointing.

Frankly, the heat hasn't been much of an issue so far (6 months usage) because our power needs are pretty low. Just a fridge, charging gadgets, lights, and sometimes the heat and fan. Our SOK 100 AH lithium battery only drains 20% per day, maybe 25% on super warm days. Solar will keep it a lot higher than that, usually 10% overnight. Most of the time our battery stays above 80% SOC. I unplug the camper, awkwardly, through a turnbuckle door on the last day or two of a trip to discharge it below 100%.

It seems like we either move every day a little bit, enough to charge it, or solar keeps it charged. The way our truck is wired we don't really get 30A, more like 25A, and it never seems to get very hot. So it charges up in about 45 minutes or less when driving.

When using our 100W flex solar panel on the ground it's only charging at around 5 amps, which doesn't heat up the charge controller. It easily keeps up a full charge if we get reasonable sun. Honestly I feel like I only use solar to save gas, which I figure is about 0.15 gallons for a charge from 0%-100%. But we've never stayed more than 3 nights without driving somewhere. The Renogy charger will produce some charge amperage even in cloudy weather, especially if we add our other 90W suitcase panel.

Basically I'm very satisfied with the Renogy dual controller and the SOK lithium battery. I'm sure the other name-brand battery manufacturers are good also. (Except our older SOK battery Bluetooth doesn't report state-of-charge correctly, so I got a cheap non-Bluetooth SOC monitor.)

Yes, this forum is fantastic for many reasons! I'm curious how Mr. Ski3pin will reply to this, as he has much more experience.

 

[TacomaAustin]

Other reasons for the 30A dual-charge controller besides less heat: less stress on the alternator,

(Aside from its $200 price when marked down), just like Rubber legs stated, the main reason I went with the smaller charge controller was to minimize the strain on my 18 year old, 130 amp alternator in the Texas heat. The 30 amp Renogy dual input charge controller has been in continuous use for only 1 year. I used #6 gauge wire on the run from the charger and camper to the truck battery.

I had been using an older CTEK unit and an AGM battery for about seven year. Unfortunately, the CTEK did not offer the correct charging profile for my LiFePO4 upgrade.

Quirks: I have a 175 watt panel on the camper's roof - which is connected to this charge controller. So, when I'm driving during daylight hours, the maximum number of amps that it will draw from the alternator is about 15 A. The charge controller prioritizes solar.

So far so good, fingers crossed. My main worry is the Renogy DC-DC with MPPT charge controllers have some terrible reviews on Amazon.

 

[rubberlegs]

That’s a good point. If you have solar on the roof, the alternator side will only draw half amps on that particular Rengy charger. So that’s a way to mitigate heat. we don’t have roof solar, so ive seen 25-30 amps.

 

[ski3pin]

Heh Ski3pin,

I wanted to follow up on your experience with the Renogy controller. Are you satisfied with the performance and system design after several months of use? You mentioned in your review that you didn’t note much heat emission from the controller. What is the heat level when the unit is charging via the alternator? I’m planning an electrical system upgrade on my Panther and researched products from Renogy, Victron and Redarc. The Renogy appears to have a cost and simplicity advantage.

The Panther came with a Renogy solar controller, 160 watt solar panel and a 79 hour AGM battery. I added a Renogy bluetooth connection to the controller and a battery SOC monitor. I plan to upgrade to a dcdc charger and 100 amp hour Battleborn. I am inclined to just make this an all Renogy system but, then again, buy the best tool first and only cry once.

Any feedback on the Renogy system will be appreciated.

I think the WTW forums are great, in more ways than one. Thanks to all who make this such a useful resource.

Julie and I just returned from an extended adventure. The Renogy system works well, well enough that I hardly think about it. Just the way I want it. Three times we parked in mostly shade for three to four days. The lowest the 100amp hour battery got to was 75% SOC. Our power needs are small - part of the system planning. Our chest style 51 L truckfridge is the main consumer of power in the summer. I have noticed no issues with heat during charging from the alternator - max of 25 amps since we have solar. Of course I'm driving at the time and am not inside the camper with my hand of the unit. But, I've not felt or seen any heat issue.

It keeps working and I don't have to think about it. Julie has the DC Home app on her phone and she gets curious about it and checks the app during trips, such as SOC in the morning and how much recovery during the day parked mostly in the shade. "Little Miss Technology," who would have thought?

 

[Defulmmt]

Thanks all for the feedback. The amp limit when the controller is coupled to solar led me to order the 50 amp version. I also ordered Blue Sea 80 amp breakers and 6awg cable.

I really enjoy the dc tutorial I learn on this forum. It’s got me thinking about building a 5kw backup system for the house.