Renogy DC DC Charger w/ MPPT

[boondox]

Curious if you are putting your hand on the cover (the "front"), or on the cooling fins (the "back").

On the top, where I get some fin and some cover. Next time I give it a run I'll use a non-contact thermometer on it and get a number. I'll make sure to get the heat sink. But in any case, it just doesn't get hot.

 

[dirt diggler]

Thanks for the reply.

Did you need to do anything with the D+ pin?

I'm currently using an AC battery charger to charge the (current) single AGM battery I have before building a multi-battery system but you need to set the battery type each time you turn it on which would be a pain if it were permanently collected and stowed away with the batteries.

No but i dont have a smart alt so the DCC just acts as VSR

 

[dirt diggler]

Can I plug in my old AGM charger into the DCC30S or 50S (still waffling on that decision)? So I'd have three inputs:

1. Solar into the PV input.
2. Alternator into the alternator input.
3. Iota DLS-30/IQ4 120VAC - 12VDC charger also into the alternator input. It puts out Bulk 14.8V, Absorption 14.2V, Float 13.6V. Or I could try tweaking the voltage as described in another thread on this site (here).

The DCC50s manual says it will cut off at 16.5V, back on at 15.5 on the ALt input so as long as you stay below that it shouldn't be a problem, on paper.
Don't forget the starter battery is on the other end of the alt wire so it will see those voltages, if it's an FLA they are a bit high and will boil it ?

 

[rubberlegs]

Don't forget the starter battery is on the other end of the alt wire so it will see those voltages, if it's an FLA they are a bit high and will boil it ?

Thanks, I'll check what kind of battery it is (2018 Tacoma). That's right, I'd be taking the Bluesea Automatic Charging Relay out of the circuit, so there'd be a direct connection. Maybe I should disconnect the Iota DLS-30/IQ4 from the battery system, or reduce it's voltage if I'm successful.

Dirt Diggler. Ha! Great name.

 

[rubberlegs]

Don't forget the starter battery is on the other end of the alt wire so it will see those voltages, if it's an FLA they are a bit high and will boil it ?

Y'know, the starter battery is over 4 years old. Might be good to replace with an AGM, and all is good with my wiring suggestion?

 

[brb58]

I've read that this unit (DCC50S) gets pretty hot.

Well...if it's 95% efficient and it's producing 50A @ 14V, that's 35W. Spread across a large heat sink, that won't be very hot.

A Victron MPPT is around 98% efficient.

 

[Hedges]

https://www.victronenergy.com/upload/documents/Datasheet-SmartSolar-charge-controller-MPPT-150-35-&-150-45-EN.pdf

Voltage 12/24/48
maximum efficiency 98%

You may be comparing a DCC505 at 12V with Victron at 48V.
Don't be surprised if Victron efficiency is comparable at 12V.
I think losses come from current (squared) and from how much voltage conversion is occurring.

 

[brb58]

https://www.victronenergy.com/upload/documents/Datasheet-SmartSolar-charge-controller-MPPT-150-35-&-150-45-EN.pdf

Voltage 12/24/48
maximum efficiency 98%

You may be comparing a DCC505 at 12V with Victron at 48V.
Don't be surprised if Victron efficiency is comparable at 12V.
I think losses come from current (squared) and from how much voltage conversion is occurring.

https://www.victronenergy.com/upload/documents/Datasheet-BlueSolar-charge-controller-MPPT-100-30-&-100-50-EN.pdf

Says 98% and does not split it out for 12 or 24v like every other spec in the chart. BTW...I have calculated myself the input wattage vs output wattage when I use mine and it's darn close to 98%. I am using panels that are 20Vmp and in parallel since they don't have bypass diodes. I am sure it might be different at higher input voltages but a pretty good comparison with this Renogy POS.

 

[Mash]

Renogy told me to get the 30Amp version vs. the 50 Amp version for my RV project. Should I return the 30 and go with the 50?

It will be a Class C motorhome, with 4x100W panels and two Lithium 100Ah batteries connected to the stock alternator that came in the Ford E450 chasis. I have no idea how many Amp the alternator is.

 

[John Frum]

Renogy told me to get the 30Amp version vs. the 50 Amp version for my RV project.

What was their reasoning?

 

[Mash]

What was their reasoning?

I don't know exactly. I think because they didn't know the specs for the alternator which I don't know as well

 

[John Frum]

I don't know exactly.

Always good to know the reason why.
Helps to determine if the opinion is makes sense.

 

[HRTKD]

I don't know exactly. I think because they didn't know the specs for the alternator which I don't know as well

It depends on which engine you have. Gas or diesel? The diesel should have two alternators, 110 amps each. The gas engine should have a 130 amp alternator. Either way, that's not a lot of amps and I would tend to go with the Renogy 30 amp option if I could hold my nose and buy Renogy.

 

[Mash]

Always good to know the reason why.
Helps to determine if the opinion is makes sense.

Yeah, which is why I am confused. So I don't know what to do. The 400 watt with alternator diagram says the 50amp but the link goes to the 30 amp version. so.....?

 

[Mash]

It depends on which engine you have. Gas or diesel? The diesel should have two alternators, 110 amps each. The gas engine should have a 130 amp alternator. Either way, that's not a lot of amps and I would tend to go with the Renogy 30 amp option if I could hold my nose and buy Renogy.

It is Gas, thanks. Yeah, I went renogy because of the videos here...... so I guess wish me luck.....

 

[John Frum]

Yeah, which is why I am confused. So I don't know what to do. The 400 watt with alternator diagram says the 50amp but the link goes to the 30 amp version. so.....?

How fast do you want to charge and how much excess capacity does your alternator have?
Did you already buy stuff or are you still in the planning phase?
I hope you are still in the planning phase because you clearly still have un-answered questions.

 

[Mash]

How fast do you want to charge and how much excess capacity does your alternator have?

I am ok with it taking a bit longer. If I drive four hours, it would be nice to get a good charge.

Hopefully the solar when stationary will charge them.

No idea on the alternator.

 

[bedpan]

I am ok with it taking a bit longer. If I drive four hours, it would be nice to get a good charge.

Hopefully the solar when stationary will charge them.

No idea on the alternator.

You can buy the 50 and via app set it to lower charge rate... Not much more for the 50 and more options in future...

 

[John Frum]

I am ok with it taking a bit longer. If I drive four hours, it would be nice to get a good charge.

Hopefully the solar when stationary will charge them.

No idea on the alternator.

Be aware that the 50 amp charger will only pull 25 amps from the alternator if there is any solar production at all.

 

[fratermus]

I think because they didn't know the specs for the alternator which I don't know as well

This would be a good time to find the actual specs on the alternator. Rated output might be stamped/labeled on the alt, or you can use a Ford-specific VIN decoder to see what it came with. Once you have the rating check out this excellent video to see how the rating relates to battery charging duties.