Hunter 49 / M-H 50 wiring diagrams

Feb 11, 2019
31
Hunter 29.5 Bristol, PA
Thanks, Dave. I've seen these schematics before, but I was hoping I could find a wiring diagram for the DC system. This has a schematic for the DC wiring harness, but I don't know how to read that as a wiring schematic. I've seen these for some other Hunters, just not the 49/50.
 
Jun 17, 2022
411
Hunter 380 Comox BC
Pages 9/10 are pretty descriptive .... shows the harness layout, connection points, wire numbers (should be printed on the wires ?)...

Anything specific we can help you out with?
 
Feb 11, 2019
31
Hunter 29.5 Bristol, PA
Hi marcham.

I'm installing Lithium Batteries (I know, kinda trendy, but we plan on full-time cruising in the fall and the existing batteries are a little old). There are a few things I need to sort out, and thought the diagrams might help.

- I've heard that some of the Hunter models have a solenoid that parallels the house and starting bank when the engine key is engaged.
- I've not yet sorted out the charging system
- I've also not yet sorted out how the windlass and bow thruster are wired in

It's all stuff I can map out on the boat, just that right now I'm a few hours away trying to map out the new system and can't get to the boat for a bit.

JR
 
Jun 17, 2022
411
Hunter 380 Comox BC
The risk of relying on the OEM wiring diagrams for this kind of stuff is that previous owners may very well have "improved" the boat with their own modifications. On mine for example, the solenoid was manually activated by a breaker instead of by the ignition power...

1. Identify your goals and use cases.
a) what will be your charge sources at the dock?
b) what will be your charge sources while under way (engine) ?
c) what will be your charge sources at anchor?
d) How do you use the boat? live aboard ? weekends? overnight at anchor or at the dock? do you run a toaster and espresso machine in the morning or use the propane stove for cooking? Are you pulling the propane gear out and going all electric? Will you maybe go all electric in the future?
e) where do you cruise? how much sunlight do you get? does the boat have solar?
f) what alternator (s) do you have? do they need to be upgraded to match the new lithium house bank? There's no point having 1000 Ah of lithium if you only charge them at 30A with a dc-dc charger while under way.
g) do you have a generator? are you keeping it?
h) do you need/want to run AC on lithium? many of the new Air Cons work well on batteries/inverter, if you have enough solar and sun to keep up

2. House batt charging

to get the full benefit of Lithium, you really want to charge your house battery from the alternator. This means installing an alternator regulator that has a temp sensor and regulating the charge output based on alternator temp. Alternators are designed to run up to 100 deg C. Limiting this to 80 deg C will extend the life of your equipment.

some boats have 2 alternators. a small one for the start batt, a large frame one for the house batt.

This means you probably want a means to charge the start battery .... this is usually accomplished with a DC-DC charger. You can setup the DC-DC charger to only activate when the ignition is ON (recommended). This way, on shore power, you can have seperate 120V charge sources (inverter/charger for house bank, and a 7A 120V charger for the start batt).

3. Engine starting.

Do you want to start the engine only on the start battery or be able to use an emergency crossover from the house batt? Many of the modern Lifepo4 BMS have a high enough current limit to start most small diesels. You can do this with a 1/2/off switch (for engine starter) or with an ON/OFF switch for the start battery and then an emergency parallel switch to link the house batt to the load ide of the start batt on/off battery switch.

4. Boat audit

Before doing anything, I'd spend a day crawling through your boat and drawing out the DC/AC electrical system. This includes pos, neg, neutral, bonds, etc.... Everything from the AC input shore power to the AC circuit breakers. Then everything from the batteries to the DC panel breakers / alternator / starter. Note wire gauges for the DC size, fuse types and sizes.

5. Design

Once you have a detailed wiring schema and know the fuse sizes, wire, sizes, etc...

a) select your batteries. where will they fit? what will be the wiring run lengths? If you parallel multiple batteries, ideally the pos and neg wires from the batt to the bus bars should be identical length. From there, you will have class-t fuses and then cabling going elsewhere in the boat.

b) Hot (always on) dc bus. This is for your charge loads that are not disabled with your normal on/off house switch. Ie: shore power charge,MPPT chargers,Inverter/Charger, etc...
Note: you'll need a service disconnect (on/off) at the battery and at the alternator. I also install them for the cable from the hot dc bus to the alternator so I can work on the engine safely without shutting off dc power).

c) alternator / regulator. You need a means to regulate the output to avoid overloading the alternator. Wakespeed, Electromaax make good regulators. If you have never programmed these, I'd suggest hiring a professional that is familiar with your regulator and batteries. Mistakes here can be costly

d) load dump. In case there is a design error, your BMS may disconnect the batteries. Not an issue on shore power, but running on alternator this can be very expensive. Balmar and others sell a load dump to catch the voltage spikes should this happen.

e) wire chases. do they still have room? is there pull strings in them or do you need to spend 2-3 days pulling strings in each chase?

f) Draw it out. If you've never wired a boat from scratch, it might be worthwhile to hire a marine electrician to design this for you. Some marine electricans will do this remotely. Pacific Yacht systems does a lot of remote design. They will draw out a detailed system diagram and help you select components to achieve your goals. Pacific Yacht Systems: Marine Electronics And Electrical Systems, Marine Boats Vancouver, Sailboats Vancouver, Boats Electronics (they also have lots of resources such as youtube videos, how-to, diagrams, etc...)

g) Windlass. Once you go to lithium, you can switch it from the start batt to the house batt. Some boats have a relay that only power the windlass when the alternator is running. I usually disable this as I want to be able to use the windlass in an emergency at anchor without having to start the engine. Bow thruster .... you have options. Some use a DC-DC charger, some wire it to the alternator, etc....

Once everything is figured out, it's about a week's work for an experienced marine electrician. If you haven't crimped and heat shrunk several thousand connectors, plan for 3 weeks. You'll need a lug crimper (not a hammer!), good terminal crimp, good quality terminals and heat shrink, support cables every 18 inches.... It may be worthwhile to buy access to ABYC standards while you do this project.


In terms of costs, if you do it yourself: Add up the cost of the new batteries, inverter/charger, MPPT chargers, solar panels, etc.... Then add 50pct to that total. That will roughly cover fuses, wiring, switches, terminals, and other supplies.

On our H38, we were at about CAD $10 000, diy (600W solar, inverter/charger, CerboGX, new switches, alternator regulator,630Ah lifepo4, wiring, fuses, bus bars, terminals, tools, etc...). I figure I spent about 70-100 hrs on the project at the boat, not counting research and design time at home or the time I spent auditing the boat and pulling strings in all the cable chases. A dock neighbor hired a marine electrician for the same on his Beneteau 391, took them just under 2 weeks.

For now, you might enjoy going through the PY Systems videos and tutorials on their website? Victron also has lots of sample installation diagrams.

Given the cost of the equipment, this is not a good project for someone new to marine electrical. Making a programming mistake can damage thousands in hardware or make the power unreliable away from the dock. If you have difficulty following the wiring diagrams in the OEM manual, it might be a good opportunity to learn by finding a marine electrician that will allow you to assist them with the project. You'll get to learn how to do and will understand your boat and systems very well by the end.

That's a big jump from a 29 to a 49! Have fun. Don't cheap out on components..... look for high quality packs, ideally those that communicate with Victron (SOK, Epoch, Victron, etc...). Program all your charge sources conservatively at first (ie: 13.7-13.8V), lower alternator output and inverter/charger output and monitor how the system does.
 
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Feb 11, 2019
31
Hunter 29.5 Bristol, PA
Wow, I really appreciate your thoughtful and detailed reply. I've done a lot of wiring on smaller boats (old tech), and rewired one boat 2 times (my first run had some shortcomings and after a decade was ready to be redone), but nothing as big as this. Some aspects, like the programming, do concern me. But the labor cost alone for 2 weeks in my neck of the woods for a single guy would be well over $16k. So I'm going to roll up my sleeves and dig in. I'll take a bit of time to digest your note, but I will. I'm reasonably 'techy' (retired scientist) and have been learning as much as I can. I may also hire a consultant to look over my plan and make sure it's ABYC compliant.

As for the big jump in size, the 295 was to introduce my partner and her kids to sailing (I also have a Santana 525 that we club race). I've sailed since I was a kid and have done a lot of offshore sailing, mostly on a 52' cutter. So, while I have a lot to learn, I'm starting at a good place.

Again, thanks, now I'm off to digest.

JR
 
Jun 17, 2022
411
Hunter 380 Comox BC
Cool ...

In a nutshell, here's what I've learned over the years rewiring boats:

Anything critical, use marine tinned wire (yes, even the 4/0 for the starter and batteries...). Non essential systems can use bare copper, so long as the sheath is oil/water resistant and fire retardant. No silicone insulated wires onboard. No aluminum wires onboard. No welding cables. No household solid core copper. Everything has to be stranded.

Heat shrink all connectors, including battery lugs, use the heat-shrink ring terminals when possible.

Size fuses to the wire. Fuses protect the wiring, not the devices. Class T for lifepo4 / Inverter. MRBF for start batt (optional), the rest is flexible... Blue Seas has a good chart for calculating voltage drop, wire size and fuse size. Remember circuit length for DC is round trip, AC is one way.

Use good crimpers and strippers, test your crimps. (cut a few open to see if the copper is fully compressed), pull test all of them.

Secure wires every 18 inches, avoid tight bundles. Loosely secure with zip ties / wire holders. Don't fill conduits past 80%.

Add a service loop of 1-2 feet, neatly bundled when pulling new wires to the DC panel.

Label everything .... Avery makes cable markers you can print at home Avery Template 61542 Cable Labels 1.25" x 2" | Avery.com

Keep a record of your changes, leave it onboard for the next owner/electrician.

Use the right colour wire. If you don't have it, STOP, wait till you have it.... red/yellow for DC batt, yellow for DC grounds, any color except green/white/black for DC positive circuits.

Use split loom when going through a fiberglass opening. No butt connectors.... just don't do it, you'll regret it in 3,5, 10 years. Only place they are acceptable is behind the DC panel in case you have a wire that doesn't reach. There's nothing more maddening than tracing down butt connectors hidden behind cabinets, in conduits, etc...

if in doubt, refer to ABYC standards, a lot has changed in the past 3 years. AWG16 is good for most services onboard (15A or less).

Batteries have to be secured so they essentially don't move laterally and would stay put if the boat was upside down.

Protect the positives at the batteries, starter and alternator.

Do it right or don't do it at all. If you stop at 95%, you'll never come back later to do the last 5%....

The hardware/wiring/lugs, etc... will cost twice what you think. You'll go to the hardware store 10x more than you figured you would...

Have fun, take your time...Frustrated? Walk away, come back another day.
 
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Likes: jssailem
Jun 1, 2009
1,863
Hunter 49 toronto
All of the H49 j50 wiring WAS documented.
There were excellent digrams online which showed all details of every wiring section,,and there were notes of all documentation updates, etc.

it was excellent, and I referred to it often; not just for my own issues, but to help out other Hunter owners.

And then,,,,, all the extended documents got taken down by a certain individual, who did so in a very unreasonable fashion.
I literally begged with him to simply turn over the files, or I wouid personally pay the internet site hosting costs for the behefit of all other Hunter owners.’
He REFUSED to do this, and said he wasn’t going to respond to any more of my emails.
I was doing this to simply help other Hunter owners, but this guy just basically told me to “scr…. off”, and not every bother him again

So, there are lots of very helpful drawings for the H 49 & H50 out there.
Good luck getting them.

Btw,,, I contacted the really nice folks at SBO.
They are well aware of the problem, but their hands are tied on this,, as well,
Think it’s just incomprehensible that someone who has access to important technical project of how your boat was built wouid refuse to assist long time owners,,who are just looking to maintain their vessels.z
 
Feb 11, 2019
31
Hunter 29.5 Bristol, PA
Wow. That's a shame. I appreciate your efforts to rectify the situation, and I can imagine it must have been frustrating.

Thursday, I'll start tracing wires for the primary DC power distribution. Wish me luck!

BTW, I appreciate your insights on this site. In addition to the raw water pump issue, I've seen many helpful comments from you and appreciate your experience.

JR
 
Jun 1, 2009
1,863
Hunter 49 toronto
Wow. That's a shame. I appreciate your efforts to rectify the situation, and I can imagine it must have been frustrating.

Thursday, I'll start tracing wires for the primary DC power distribution. Wish me luck!

BTW, I appreciate your insights on this site. In addition to the raw water pump issue, I've seen many helpful comments from you and appreciate your experience.

JR
Thanks for your positive comments
The jerk who refused to simply supply the documents was so incredibly rude, it was beyond comprehension.
As stated, I offered to cover the cost of hosting the files, just so that I could help other Hunter owners. I’ve never had anyone respond in such an arrogant fashion to a reasonable request which would have cost him nothing.
I simply asked him as a desperate last attempt to simply put the files on a thumb drive, (which I offered to pay for).
He then said “this is final response. Do not contact me again”
For reference, this individual worked for a motor yacht company that ended up with the Hunter tech docs.
I can see no reason why this very rude individual thought it was reasonable to deprive boat owners of essential documents that he had zero use for.
If sny other Hunter owners want to contact this guy, I’ll pass along his contact info.
Good luck!!