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What else is wired directly to the battery

6K views 39 replies 19 participants last post by  RichH 
#1 ·
Things conventionally wired directly* to the battery:

- bilge pump
- gasoline/propane detector
- what else?

* wired directly: wiring goes directly to the battery, not through a breaker/fuse panel. There might be a fuse between the device and the battery, as specified by the device manufacturer.
 
#2 ·
Hey,

I have the bilge pump wired directly to the battery. My propane detector is not, that's on a panel switch.

I also have a wire from the stereo directly to the battery. This is to keep the clock and other settings alive when the battery switch is off.

Lastly the output from the solar charge controller is connected to the house battery bank (2 6V).

Barry
 
#5 · (Edited)
Two banks... house and start aside from the main heavy wires....

start has:
echo charge connected to house

house has:
bilge pump under PSS dripless shaft
one always-ON 12v outlet for charging something when I am not aboard... such as VHF radio also for clock /memory of stereo
temp sensor for alternator regulator
link 20 sense wire
echo charge connected to start bank

I have something called a Pulse (de-sulfator) which is connects the house to the start. I don't think it does anything. I think I will remove it.
 
#6 ·
The only things connected to my house bank are the panel takeoffs, charger cables, smartgauge and the temp sensor.

You may note that I don’t even have the bilge pump directly connected, they (3) run through a breaker on the panel. It’s the OEM setup and I’ve questioned whether I want to change it for safety. Not sure new breakers are quite as vulnerable as old time fuses and whether that should change perspective. I do like being able to shut the pumps off, when I want to clean filters, replace float switches, etc. I’m on the fence on this one.
 
#7 ·
2 banks on my boat both have 175AMP MRBF. MOST of my connections are made at the back of the 1/both/2/off switch

Start bank - connected to the SmartGauge and 1/both/2/off switch. Echo Charge, analog volt meter, and bilge pump are connected to post 1 of the 1/both/2/off switch.

House bank - connected directly to the Alternator, a SmartGauge, a BlueTooth battery monitor, and 1/both/2/off switch. Echo Charge, analog volt meter, and stereo memory are connected to post 2 of the 1/both/2/off switch.

Because my boat lives on a mooring I have connected the battery charger (Iota DLS30/IQ4) to the Common post of the 1/both/2/off switch. I discovered that the battery charger has a high drain (like 0.10A) on the battery if it is not providing charging.
 
#8 ·
It depends on the boat.

I owned a 1979 Oday 23. The breaker panel consisted of four circuit breaker switches, one of which was a "spare". While the other switches worked (interior and exterior lights), the spare was so corroded that it was useless. I wanted to install a chartplotter, and rather than take on the replacement/refurbishment of the panel, I simply hardwired the plotter to the battery (with a fuse). My point being, it may not be worth it to wire something through the panel even if you "should" do it that way. It depends on the boat.
 
#9 ·
Just Bilge pumps for me. My pump panel is within 2' of the Battery and the nice on/off/auto panel. I did rig a guard to prevent accidentally turning them OFF because they are at my feet sitting at the chart table. Did that once and it shook me up pretty good. What's the point of bilge pumps it they're off.
 
#10 ·
I ALWAYS wire the bilge pumps (more than one), propane detectors, and VHF directly to the battery (fused). All wired for 3% or less voltage drop. You always want the bilge pumps to work and in case of emergencies you want to be able to use the VHF to call for help!
 
#14 ·
Even when something is directly wired to battery, having a fuse on the positive wire makes sense for me. On my boat just about everything is wired through the panel and almost everything also has a fuse. Island packet 35. Windlass is wired to battery bus directly but it has it’s own fuse.
 
#16 ·
Starter bank echo charge off of house bank

House bank direct wires include one of the two bilge pumps....the other is on a breaker on the DC panel. VHF direct wired also. Both are fused. House bank direct also is the DC panel and the alternator. Also have a Blue Sea ACR.
 
#18 · (Edited)
I rewired the 12 volt system about 10 years ago. I did not change any of the branch wiring for lighting, pumps etc. But I did change the lamping to LEDs.

The "mains" rewire was a big project but not difficult. It involved the following:

2 new AGMs 8Ds for the house bank
1 Optima blue top AGM for the start battery
BlueSeas Systems 8080 batter switch. This allows the house and start to be combined. and the house "switch" is a 100amp breaker.
New large busses for the high amperage connections (neg and pos) loads
Smaller round busses for lower amp loads
large fuse holders for windlass, starter, inverter, alternator output for ANL fuses
30 amp fuse block for the distribution panel / loads (lighting, pumps, electronics (more breakers) VHF etc. with both +12v and 0v busses.
Link30 monitor
solar charge regulator
echo charge
new 120-amp alternater w/ Balmar 614 regulator
All new cabling for the above - all wires/cables are fused.
1000 watt inverter.
Blue seas Systems 110 volt panel
A new battery box

This work was undertaken when during in water winter storage. It was spendy and time consuming. I planned where the equipment would be located. Measured for the cables and had them professionally made. They were sized to ABYC standards, I had to do the new batter box 1st leaving an old battery for the 12 loads during the work so I had lighting!

The main feature is that the start batt does one thing only - turn the starter. All charging is to the house bank which charges the Start battery with an Echo charge. Start battery has been completely at 100% capacity since installed.

House bank has the engine bilge pump wired to it at the main buss (it's powered 24/7/365. The Balmar regulator sense is also wired to this buss.

An always on small +12v buss was placed at / behind the main distribution panel. This buss has always ON devices connected to it.... Gas sensor, VHF, AIS, stereo memory, charging cig outlet and several USB outlets (recently added).

This is a reasonably bullet proof system. And since I wired and built it... and documented everything with drawings... it is no longer the mystery that the former mess of wires seemed to me. I also changed from a 2 battery 1-2-ALL-OFF set up to a single 2 battery large house bank and a small start battery. Sick and tired of wet cells that need maintenance! I don't have to fiddle/manage battery switching... arrive at the boat and switch both house and start circuits to ON.

Refrigeration is engine drive. This means that I can cool the box when the engine runs. I also make hot water, use the inverter (mostly to charge batteries for tools), vacuum etc.

I added a NUC small form PC with a 20" monitor. It runs on 19v via a buck transformer to the +12v buss at the distribution. Mouse and keyboard are wireless. Monitor can be set up wherever, NUC is mounted in a locker.

This system will outlast me!
 

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#36 ·
Things conventionally wired directly* to the battery:

- bilge pump

- gasoline/propane detector

- what else?

* wired directly: wiring goes directly to the battery, not through a breaker/fuse panel. There might be a fuse between the device and the battery, as specified by the device manufacturer.
If you have a SSB radio for avoding the parasites it is better to take the electricity directly from the battery.

SM-J510FN cihazımdan Tapatalk kullanılarak gönderildi
 
#37 ·
"connected directly to the battery" needs to be clarified.

Not every load which makes sense to connect to the battery needs to be connected to the battery posts.

A MAIN BUSS for +12v and 0v should be provided for "always on" loads. The battery switch can be down stream so all the loads which are controlled by the distribution panel can be on of off. You'll want as few connections as well as these are points for corrosion and failure. Wires need to be fused to protect them.

Connecting multiple wires to the battery posts is not the best idea... and not necessary.
 
#38 ·
As I think about this, it just gets less clear.

Why can't I have my bilge pump wired through a dedicated panel breaker, when most "directly wired" bilge pumps still have Auto/manual/off switches?? What's the difference?

The VHF, as previously noted, still has an on/off knob. In my case, I never actually turn the radio off, just the breaker, which is at the nav station with the radio.

No skin off my back whether anyone else wires their boat any way they'd like to. I'm just contemplating this common advice and trying to think of why I would rewire the OEM configuration.
 
#39 ·
As I think about this, it just gets less clear.

Why can't I have my bilge pump wired through a dedicated panel breaker, when most "directly wired" bilge pumps still have Auto/manual/off switches?? What's the difference?
It's really a matter of more connections and more things to fail

The distribution panel (as mine does) has rocker switchs... 2 connections... then a breaker... 2 more connections... the feed to the switch is runs to a buss on the panel and that to the +12v "input" which likely is connected to a breaker and then to another buss or to the battery post. Lots of connections as possible failure points.

Alternatively a main feed to an always on buss just reduces the number of connections and YES devices have their own on-off switch.
 
#40 ·
Usually SSB/Ham radio ... for max. power draw from the battery.
Actually there should be a single fused connection from the battery to a close-by 'distribution' / gang panel for the 'heavy draw stuff' that doesnt connect directly to the on/off/both switch, and each of the 'heavy draw stuff' with an attached switch nearby the batt - IMO.
 
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