Renogy DC/DC converter draining starter batteries

[Scubaseas]

What CatLove said. Your DC-DC D+ should not go to B+ on the alternator. It should be switched by ignition switch or on a switch or relay of some kind. The early Renogy DC-DCs do not self disconnect. It's "on" all the time the way you have it.

Love the wiring porn. Kudos to Jedi and CatLove.

[newhaul]

Originally Posted by CaptainRivet

You are not experienced so make yourself the life easy and get yourself the easy as alternator relay.
In the install notes of the relay will show you how to connect it. You have all cables needed for that relay at the DC2DC location.
Saves you complex routing of an ignition wire from.the engine panel to the DC2DC locations for both engines.

The easy as relay discovers the ripple only an alternator produces and switches then on the DC2DC and when alternator of switches DC2DC off. So this cannot be fouled by other charge source as thats the case with all DC2DC as they work via voltage sensing. Eg all the victron put your shorecharger on and you see how the DC2DC starts charging the house as it gets fooled by the shorecharger thinking the alternator is running.
https://www.caravansplus.com.au/easy...c7xeJKLh7tUqjk
This is far more then a classical voltage sensing relay!
As jedi said yes replace both fuses and fuse holders, that's really bad.

Installing the unit iaw manufacturers manual will solve the issue as the b+ wire is supposed to go to the ignition run position so its only energized when the engine is running.

[CatLove]

Originally Posted by CaptainRivet

How old is your installation?
It will look good know but that plastic ducting is for house install, not boats and will over time bridle an cracking.
Jedi's install pics are top notch and as Putt-putt commented right an old but simple art that holds up in marine install for decades. It takes a bit more time but is far superior to what you have.

Nope, the pics are neither from house installations nor from my boat.

They are proper marine installations, the first from a superyacht and the second from a new 2 million USD 60ft cat.
There are large numbers of similar installations and haven't seen any being cracked or damaged in any way.

Sorry again but no, the various types of plastic conduits , looms, DIN rail terminal blocks, etc do not crack over time any more than the wire insulations, boat hulls and the other gazillion plastic pieces used on boats.



I'm not saying at all that old skool stuff is bad, only that it has disadvantages that I already listed in my previous post.


Electric panels aren't even exposed to the sun . There's no truth to your statements in this respect .

[Scubaseas]

That's a waterproof ATC/ATO fuse holder. It's just out of it's cover. https://boatplicity.com/9053287-seac...tm_content=AG1

[newhaul]

Originally Posted by Scubaseas

That's a waterproof ATC/ATO fuse holder. It's just out of it's cover. https://boatplicity.com/9053287-seac...tm_content=AG1

Excellent thank you for the reply.
Been working on cars the last 5 days is all.

[s/v Jedi]

I use a waxed polyester flat thread that used to be common but harder to find today. Still on Amazon.

It doesn’t actually takes much longer once you’re experienced in its use and was used often in the early 80’s when people could still acquire such skills

But note that I only use this for fixed parts of the installation. A picture I often post is a module consisting of a red GPO-3 fiberglass board with four Victron Orions mounted and a cable loom. This wiring never has to change until these Orions aren’t available anymore and they need to be replaced.

For regular bundles I also use plastic wire ties, sometimes the velcro style initially while wires get added, then replace with regular ones.

I also use the grey plastic “finger channels” where handy. These all work great.

Some more pictures to show how much effort it takes to build installations like these…

[CaptainRivet]

Originally Posted by CatLove

Nope, the pics are neither from house installations nor from my boat.

They are proper marine installations, the first from a superyacht and the second from a new 2 million USD 60ft cat.
There are large numbers of similar installations and haven't seen any being cracked or damaged in any way.

Sorry again but no, the various types of plastic conduits , looms, DIN rail terminal blocks, etc do not crack over time any more than the wire insulations, boat hulls and the other gazillion plastic pieces used on boats.



I'm not saying at all that old skool stuff is bad, only that it has disadvantages that I already listed in my previous post.


Electric panels aren't even exposed to the sun . There's no truth to your statements in this respect .

Then that's the professional channels for marine and heavy industrial use but usually you see in leisure boats the stuff from home depot or alike which doesn't lasts long at all. Cannot see difference in the foto.
It's not UV as they never see sun, thats clear. What's exactly causing this no idea.
I just lately came across 2 YouTube videos showing that, let me see if I find them again.

[CaptainRivet]

Originally Posted by newhaul

Installing the unit iaw manufacturers manual will solve the issue as the b+ wire is supposed to go to the ignition run position so its only energized when the engine is running.

Yes but he is unexperienced and for running 2 ignition wires from each engine panel to DC2DC can be a task of ripping half the boat apart to root that cable. Then he needs to find ignition on instrument panel and depending on manufacturer you need to hack into their wiring loom....too many mistakes can be done here+effort, especially for unexperienced.
Much easier to use that easy as relay as everything he needs for that is present at then location of the DC2DC. It simplifies the installation enormously and is fool proof compared to the voltage sensing+ignition, also the victron. Also if ypu pay an installer it's cheaper to get that relay then installer rooting 3h cables.

At that easy as relay which solves a lot of other issues the ignition wire cannot solve.

[Scubaseas]

OP only needs to power the DC to DC charger with the D+ wire which can come from the ignition switch or the back of the alternator or any other switched power supply. Yes the EasyAS autosense relay would work but he really only needs to use a keyed or switched power to the DC to DC itself. The way the wiring diagram is now has the DC to DC on all the time.

[Opie91]

Originally Posted by s/v Jedi

I use a waxed polyester flat thread that used to be common but harder to find today. Still on Amazon.

It doesn’t actually takes much longer once you’re experienced in its use and was used often in the early 80’s when people could still acquire such skills

Never mind the wax polyester thread will outlive just about any tywrap.

[Tin Tin]

Get a second DC DC charger and avoid the complications, will also give redundancy, which twin engine boats are great for. In addition when you do run two engines you will be putting 40 amps into the system.

[CaptainRivet]

Originally Posted by Scubaseas

OP only needs to power the DC to DC charger with the D+ wire which can come from the ignition switch or the back of the alternator or any other switched power supply. Yes the EasyAS autosense relay would work but he really only needs to use a keyed or switched power to the DC to DC itself. The way the wiring diagram is now has the DC to DC on all the time.

Exactly 100% all the time on and depending engine manufacturer, location of the instrument panel and accessibility of the engine loom is a lot to consider....can you tell him where to find exactly the inigition wire in the engine loom?
Add to that then rooting that D+ wire which can be a 30min or 3 days task riping half the I assume cat apart.
If it's a 30min task and instrument panel and ignition cable is easy to acess with cable shoe on the ignition switch of both engines then root your 2 D+ wire...
Seeing that spaghetti installation my advise is easy as relay, it will be cheaper in the end and will 100% work with much less pita. He needs only one relay as it doesn't matter if 1 or 2 engines run and which. Easy as relay detects ripple of a running alternator and switches DC2DC on and all he need of cabling is already at the DC2DC spot.

[CaptainRivet]

Originally Posted by Tin Tin

Get a second DC DC charger and avoid the complications, will also give redundancy, which twin engine boats are great for. In addition when you do run two engines you will be putting 40 amps into the system.

That doesn't sort his issue. But yes a 2nd one won't hurt.

[Putt-Putt]

s/v Jedi, I have always admired your work. I am nowhere near your quality but am working to get there. My nemesis is likely time.
I certainly know that space on any boat is usually at a premium. As a result, different systems may need to reside in the same space as other unrelated systems.

That being said, what is the reason for a 3/8"+/- SS cable to SS? chain connection to take place in what appears to be an electrical cabinet?

From the look of the cable clamp, things may have been wet in the past!

[s/v Jedi]

Originally Posted by Putt-Putt

s/v Jedi, I have always admired your work. I am nowhere near your quality but am working to get there. My nemesis is likely time.
I certainly know that space on any boat is usually at a premium. As a result, different systems may need to reside in the same space as other unrelated systems.

That being said, what is the reason for a 3/8"+/- SS cable to SS? chain connection to take place in what appears to be an electrical cabinet?

From the look of the cable clamp, things may have been wet in the past!

Yes, that’s a location in the engine room. The electrical box and grey plastic open slot cable duct is for AC power from shore and genset. Additional parts visible are a Progressive Power Management Center for a 120/240V 50A feed from shore and a Yandina galvanic isolator.

The chain and cable is part of the steering system. The chain connects sprockets of two steering wheels with the cable that attaches to the rudder quadrant. The engine room is a dry but high humidity place and the steel cable will be replaced with Dyneema when I think it’s time. The visible corrosion is only superficial and doesn’t worry me, especially since steering is almost always done with hydraulics.

The cable duct is to protect the cables from that chain and also to make it a neat install.