Renogy 60A DC-DC charger in 2016 Pleasureway

[markopolo]

Originally Posted by reilym

.............. Once I figure out how to get wires from the cab back to the DC-DC.................

What are the wires for? Are they for the DVB01 V+, V-, DC- & DC+? If so, maybe the new wire run is not needed. Could those inputs come from the heavy gauge wires that go to the Renogy unit input?

[reilym]

I also thought about using that exact lead acid profile. It is true that my Dometic fridge gobbles about 15 amps when on battery, which it is powered when driving. Definitely worth keeping that as a option. I will run your thinking about post-charge loads pulling down the battery by Renogy and see what they say.

My take on Function 4 is that the relay is active only when the voltage is between the upper and lower limits. As such, if stress pulls the alternator voltage down to the upper limit, you would want the DC-DC to immediately drop the demand (through LC+) and return it when the voltage comes back up. Unfortunately, the time delay is fixed to the set point, so one could not have the off delay zero and the on delay non-zero. I have to think about this some more, but rather than pontificate, it's probably best if I go put one of these on my power supply and start experimenting.

[reilym]

Originally Posted by markopolo

What are the wires for? Are they for the DVB01 V+, V-, DC- & DC+? If so, maybe the new wire run is not needed. Could those inputs come from the heavy gauge wires that go to the Renogy unit input?

Yes, that is how I am turning it on now, a short run from D+ to the cable coming from the alternator. The use of the DVB01 for automated control will not require running any new wires, But if I want to be able to control things manually from the drivers seat, I'll have to run wires. According to PW, the only real way to do that is by going under the van. That will be a totally separate project with lower priority.

[markopolo]

I might not be understanding the delay setup & will have to review.

It appears that the 12V DVB01 relay coil can handle up to 15.6V.


coil max voltage.JPG

[reilym]

The DVB01's worked out well on my bench. I connected DC+, V+ and COM to the positive side of my power supply and DC-, V- to the negative side. the NO terminal was connected to the negative side through a small 12V lamp. I was able to program voltage limits and time delays to my satisfaction. By adjusting the power supply voltage, I was able to mimic changes observed in the RV with expected results. In the RV, I'll use the alternator feed into the DC-DC for DC+, V+ and COM. It's a cheap power supply, but with the relay off, the DVB01 was using 0.01 A and with the relay on 0.04 A. I am attaching my re-translated manual, including a programming example. Let me know if there are any corrections, omissions or typos.

One thing that I only understood after experimenting on the bench was that the time delay parameters P4 and P5 are not associated with the upper and lower voltage limits per se, they are associated with relay activation and deactivation. This makes more sense and I think is more useful.

What I will try in the RV is as follows:
For D+:
Function 3
Power on at 13.2 volts, 30 second activation delay
Power off at 12.8 volts, 5 second deactivation delay

This should turn on the DC-DC 30 seconds after the alternator starts spinning and off 5 seconds after it stops.

For LC+:
Function 4.
Power on between 12.8 and 13.1 volts, 0 activation delay, 5 second deactivation delay.

This should immediately reduce the total load by 30 amps if the alternator gets overtaxed and restore it 5 seconds after it recovers. I might adjust the higher voltage limit up after I make some observations in the field.

[markopolo]

Your instructions are much easier to understand. It was very nice of you to do the re-translation.
just a few suggestions:


page 1
input voltage correction --> fine as it is but maybe could be correction/calibration

page 2
*Note: Relay activated means current flows through normally open (NO) terminal and the no current --> remove the

page 3
III. Wiring Instructions
The DVB01 module requires a DC 5V/12V/24V power supply --> fine as it is but maybe could be supply/source

page 4 - probably not re-translated
Tips: If user load and DVB01 module use a same power supply --> the could replace a & maybe add source to power supply/source

[reilym]

Updated with markopolo's suggestions. Thanks!

[markopolo]

That's great.


------------------------

Originally Posted by reilym

................
What I will try in the RV is as follows:
For D+:
Function 3
Power on at 13.2 volts, 30 second activation delay
Power off at 12.8 volts, 5 second deactivation delay

This should turn on the DC-DC 30 seconds after the alternator starts spinning and off 5 seconds after it stops........................

Just a note: If Float is enabled on the Renogy or other loads present in the coach then the shut down could/should happen within 5 seconds. If no float or no other loads then the shut down would happen at 12.8V so could take longer. There's "surface charge" that would need to be used up. I'll still go with 12.9V here because it would leave the chassis batteries a tiny bit more full. I have dual AGM's for starting batteries in my diesel van so the "surface charge" available would be greater than a single wet cell chassis battery for example. Also, AGM's can rest at slightly higher voltage than wet cells.

Every setup will probably be just a little bit customized but much easier to do with the new instructions.

[markopolo]

Benefits & possible downsides to adding the DVB01 to Renogy 20/40/60 installation - feel free to add more.

#1. Chassis battery protection. Without DVB01, if ignition or other switch left on chassis battery drain would result, all the way down to 8V I think. With DVB01 added, the Renogy 20/40/60 will turn off at the low voltage set point you choose. 12.8V for example.

#2. Chassis battery cycling reduced. Likelihood of in-use (other than starting) voltage dips below 12.8V for example are much reduced / possibly eliminated so easier use of chassis battery should mean longer chassis battery life.

#3. Alternator stress reduced. The DVB01 adds "smart" load shedding to the installation. Two levels or stages of load reduction can be added.

#4. Permits easier wiring / reduced interference with OEM chassis wiring.

#5. It adds a voltmeter to the coach.

-------------

Possible downsides:

#1. DVB01 failure. As with any added component, unit failure would be disruptive.

#2. Constant power use if power source not on a switch. With power saving On I calculated it could add 4Ah per month to existing chassis battery drain. Anyone could check that calculation & report back. If only 4Ah per month then probably not much of a concern for most.

[booster]

Originally Posted by markopolo

Benefits & possible downsides to adding the DVB01 to Renogy 20/40/60 installation - feel free to add more.

#1. Chassis battery protection. Without DVB01, if ignition or other switch left on chassis battery drain would result, all the way down to 8V I think. With DVB01 added, the Renogy 20/40/60 will turn off at the low voltage set point you choose. 12.8V for example.

#2. Chassis battery cycling reduced. Likelihood of in-use (other than starting) voltage dips below 12.8V for example are much reduced / possibly eliminated so easier use of chassis battery should mean longer chassis battery life.

#3. Alternator stress reduced. The DVB01 adds "smart" load shedding to the installation. Two levels or stages of load reduction can be added.

#4. Permits easier wiring / reduced interference with OEM chassis wiring.

#5. It adds a voltmeter to the coach.

-------------

Possible downsides:

#1. DVB01 failure. As with any added component, unit failure would be disruptive.

#2. Constant power use if power source not on a switch. With power saving On I calculated it could add 4Ah per month to existing chassis battery drain. Anyone could check that calculation & report back. If only 4Ah per month then probably not much of a concern for most.

I have been following along on this as the whole idea of having the capability to turn stuff on and off based on voltage, amps, temps, etc seem to be the missing link in a lot of the things we talk about here.


I was wondering about the parasitic as that was one of the things that was always of issue when I was messing with ways to control the charging by amps with the Blue Sea charger that measured amps internally. Relays etc can add up quite quickly, especially if they are the larger amp stuff especially.



Of particular interest to me would be controlling stuff off of temperature in relation to the alternators, and I would be fine with just a good readout gauge and field shutoff switch setup. Our remote regulator doesn't have temp compensation so we need to be careful. The thermocouple system I made lasted long enough to get good setup information but is not very durable as the wiring breaks, gets resistance, etc. I did contact Glowshift gauges to see if they would think about making a ring terminal temp sensor for their new, really slick, dual readout digital gauge. I am going to put one in the Buick to read oil pressure and trans temp in one small gauge. I had a short thread about that gauge a while ago.


It has been a fun read for me

[reilym]

Originally Posted by booster

I did contact Glowshift gauges to see if they would think about making a ring terminal temp sensor for their new, really slick, dual readout digital gauge. I am going to put one in the Buick to read oil pressure and trans temp in one small gauge. I had a short thread about that gauge a while ago.

The main motivation here was to reduce charging stress on both the coach batteries and the alternator, while trying to avoid having to add a second alternator to the Promaster. Since I was measuring up to 140 amps going back to the batteries with the SurePower battery separator, this set up should reduce my alternator burden by 60-90 amps when the coach batteries are depleted. Acknowledging that heat is the alternator killer, eliminating or reducing nonessential loads to keep the alternator cool would be ideal. With something like that, I think an input to kill or reduce the current draw from the DC-DC charger based on alternator temperature would take the sophistication of a "smart" alternator-to-coach charging system up a considerable notch.

I also agree this thread has been very enjoyable and educational for me.

[reilym]

Originally Posted by markopolo

Benefits & possible downsides to adding the DVB01 to Renogy 20/40/60 installation - feel free to add more...

Looks good to me! Regarding #1 downside, at $14, a pre-programmed spare DVB01 would be cheap insurance. Downside #2, once I am sure this system is working, I am thinking about swapping the underhood Surepower separator with a high current switch that can use used to disconnect the entire system during extended stops.

[booster]

Originally Posted by reilym

The main motivation here was to reduce charging stress on both the coach batteries and the alternator, while trying to avoid having to add a second alternator to the Promaster. Since I was measuring up to 140 amps going back to the batteries with the SurePower battery separator, this set up should reduce my alternator burden by 60-90 amps when the coach batteries are depleted. Acknowledging that heat is the alternator killer, eliminating or reducing nonessential loads to keep the alternator cool would be ideal. With something like that, I think an input to kill or reduce the current draw from the DC-DC charger based on alternator temperature would take the sophistication of a "smart" alternator-to-coach charging system up a considerable notch.

I also agree this thread has been very enjoyable and educational for me.

No question on the reducing load is the way to go on a factory controlled single alternator, nothing else really would work decently. You really can't be messing with shutting off the field or even reducing the field current with messing with the factory controls so not good to do. Taking of load is easy and safe. Temp control for that might work better than voltage, but that is far from certain.

[markopolo]

I think you can turn the Surepower off by interrupting the small gauge ground wire. Make ground On, break ground Off.

[booster]

Originally Posted by markopolo

I think you can turn the Surepower off by interrupting the small gauge ground wire. Make ground On, break ground Off.

Yes, you can, I did that for a while and also did it from the positive lead to the coil itself, both worked fine.

[markopolo]

I used Mike's instructions today. They're great. The example he provided in the Appendix lets you dive right in with confidence. If you want different settings you could copy then paste his example into Word or Wordpad etc. & edit it.

I spent a fair bit of time calibrating it. It appears to drop (& not round up) digits that aren't displayed. This is an example how one unit is set:

DMM-------DVB01
9.98V --- 9.9V
10.01V -- 10.0V
10.04V -- 10.0V
10.09V -- 10.0V
10.10V -- 10.1V

Maybe of interest - the 24V version's coil needed to see at least 13.62V to activate. That's less that the 18V guaranteed pick-up voltage so it's possible that it also could be a option for 12V RV use if the 12V version doesn't last. That minimum required voltage might vary between units. Drop-out voltage is quite low so shouldn't be a problem.

The datasheet for the 12V relay SRD-12VDC-SL-C indicates max coil voltage is 130% of the rating so 15.6V. That should be more than enough for van use. - http://www.songle.com/Public/Uploads...c81ac16e36.pdf

[markopolo]

Both this site - https://www.gotronik.pl/przekaznik-1...or-p-6988.html - and Mr. Teals YouTube video have a graphic that helps visualize the DVB01 Functions.

I borrowed from both sources and made it fit on one page for easy reference. Attached PDF: Function DVB01.pdf

[reilym]

I have incorporated the DC-DC charger into the RV, using two of the DVB controllers and am very happy with the operation. One is used to turn the unit on only when the engine is running and the controller senses > 13.2 volts for more than 30 seconds. The other limits the current to 1/2 if the voltage drops below 12.6, which happens occasionally at idle when there are lots of other loads on the alternator. The "back to full current" delay is now 30 seconds, but I plan to play with that to minimize frequent switching when I am in stop and go traffic.

The unit is under one of the ottomans and I made some wooden brackets to raise the seat 3/4" to allow for ventilation while the DC-DC charger is in use.

I also replaced the Sure Power battery separator with a manual switch using the original separator bracket. When parked for an extended period, I pop the hood and turn it off to kill the minor current draw from the DVB units. The one thing I want to do is add a switch in the cab so that I can 1) manually turn the unit off if I don't need to charge off the alternator or want to let the solar panels do all of the work, and 2) limit the current to 30 amps if that will be sufficient for the needs of the day.

[markopolo]

Thanks for posting the update & photos. That's all really nicely done

[MsNomer]

I will not pretend to understand half of what you guys are talking about, but it is relevant because MrNomer is this weekend finishing up installation of a 40A Renogy B2B in our PM with 180A alternator.

First, I am intrigued by this from Marko: "Note: The LC connection is described as needing signal input just like the D+. Also, LC is likely only needed with the 60A Renogy units because of 50% LC versus 12.5% for 40A & 20A units." What is the source? I like it better than what the manual (generic 20-40-60) says.

Second, there has been quite a bit of discussion of the PM alternator in this context on the PM forum. The general census is that it is quite robust and not prone to overheating. One member has been charging 560Ah of LiFePO4 DIRECTLY from his 180A alternator for six years with no issues. He did beef up the wiring from alternator to battery. We are adding the B2B primarily for control of the charging voltage.

Third, some people are addressing the risk of drained battery by tapping the D+ in to the fuel pump wiring.