Electrical bus bar advice

[MRWood]

I have run out of extra connections on my bus bar below my helm. I would like to add another to connect a few more items like my new radar mfd and blower fan for defrost. Here is a pic of what it looks like under helm. Can I hook up another bus to one of the top bars or use current bar to feed a new one or do I need to run new wire from my battery switch to helm and hook up that way.

 

[wolf]

Question is there fuses under the cap or just a bus bar? Ive always been told to fuse any electronic stuff..
when I changed everything over a few years back I went a bit over board and ran # 2 wire up to a block ( as it was what was long enough and kicking around ),and then new fuse bars where for all my electrical and used spade fuse connector bar. or built in ones hopefully your power cable up is big guage?
My good friend of 40 years rigs boat for a livng as he says bigggggggers better and yes he helped me

 

[MRWood]

Question is there fuses under the cap or just a bus bar? Ive always been told to fuse any electronic stuff..
when I changed everything over a few years back I went a bit over board and ran # 2 wire up to a block ( as it was what was long enough and kicking around ),and then new fuse bars where for all my electrical and used spade fuse connector bar. or built in ones hopefully your power cable up is big guage?
My good friend of 40 years rigs boat for a livng as he says bigggggggers better and yes he helped me

Yep, it’s all fused under the cap/cover. #2 wire from battery switch to cabin. I’ll get some better pics when I go into the boat in a bit.

 

[seachicken]

How exactly are you running out? I'm under the understanding that screws are only allowed 1 terminal on them but studs are allowed up to 4 terminals. From what I can see I believe that bus bar is rated to 150 amps. If you have 2 awg wire it's a touch small for full 150amps but could be just fine in your case. I'm assuming it's mostly electronics on there?

https://www.bluesea.com/products/2303/Common_150A_BusBar_-_Four_1_4in-20_Studs

 

[seachicken]

And you want something like this at the battery end if you don't already: https://www.bluesea.com/products/7720/AMI___MIDI_Safety_Fuse_Block

 

[MRWood]

How exactly are you running out? I'm under the understanding that screws are only allowed 1 terminal on them but studs are allowed up to 4 terminals. From what I can see I believe that bus bar is rated to 150 amps. If you have 2 awg wire it's a touch small for full 150amps but could be just fine in your case. I'm assuming it's mostly electronics on there?

https://www.bluesea.com/products/2303/Common_150A_BusBar_-_Four_1_4in-20_Studs

The dual bus in pic is rated at 100amps.
Are the studs you’re referring to the 4 post bars above the dual bus? Can I run another fuse bus bar off one of the studs?

 

[MRWood]

Here are some more pics of my system that was put in last year. The shop doesn’t have a schematic of it so I’m somewhat blind as to what does what. I could go to the APM and have them do it but didn’t want to trailer to Port just to add a bus bar.
It’s just electronics and lights on the dual bus under the helm.
1st pic is batteries.
2nd pic is switch etc in transom
3rd pic is a better shot of buses in helm

 

[Corey_lax]

Here are some more pics of my system that was put in last year. The shop doesn’t have a schematic of it so I’m somewhat blind as to what does what. I could go to the APM and have them do it but didn’t want to trailer to Port just to add a bus bar.
It’s just electronics and lights on the dual bus under the helm.
1st pic is batteries.
2nd pic is switch etc in transom
3rd pic is a better shot of buses in helm

I think you need to get some dielectric grease on those. Looks good though.

 

[seachicken]

I think you're referring to your fuse panel as a dual bus? The 4 stud bars above are bus bars. The panel with the fuses and grounds is a fuse panel. If those 4 stud bus bars are rated to 150 amp and your combined load isn't exceeding your feeder wire (2 awg is 120 amps on the blue sea chart) you could add another fuse panel off a stud on the bus bar. Your existing fuse panel is rated to 100 amps and looks close to the limit with 4 20 amp fuses and a few smaller ones.

I'm slightly confused why you have 2x20 amp trim tab fuses though, I'm reworking my Bennett Bolt setup now and it just needs 1x20 amp and one smaller one and one to ignition power.

Also you need to ensure your circuit protection feeding power to the helm is adequate for the combined load of everything it's feeding and the rating of the wire.

 

[MRWood]

I think you're referring to your fuse panel as a dual bus? The 4 stud bars above are bus bars. The panel with the fuses and grounds is a fuse panel. If those 4 stud bus bars are rated to 150 amp and your combined load isn't exceeding your feeder wire (2 awg is 120 amps on the blue sea chart) you could add another fuse panel off a stud on the bus bar. Your existing fuse panel is rated to 100 amps and looks close to the limit with 4 20 amp fuses and a few smaller ones.

I'm slightly confused why you have 2x20 amp trim tab fuses though, I'm reworking my Bennett Bolt setup now and it just needs 1x20 amp and one smaller one and one to ignition power.

Also you need to ensure your circuit protection feeding power to the helm is adequate for the combined load of everything it's feeding and the rating of the wire.

You are correct that I’m referring to the fuse panel as a dual bus, I’m not up on the lingo that’s for sure.
The 4 stud bus bar is the blue seas 2305 minibus 4 terminal 100amp. Will that be ok to add a fuse panel to it?
Not sure about the Bennett bolt setup for the fuses as I didn’t set them up. I do have the indicator control for the tabs rather than the rocker switch if that makes any difference.
I guess this next pic is my circuit protector going to the helm. Although I wouldn’t bet my savings on it lol. It’s a 100 amp. It’s under the transom near the battery switches.

 

[seachicken]

You are correct that I’m referring to the fuse panel as a dual bus, I’m not up on the lingo that’s for sure.
The 4 stud bus bar is the blue seas 2305 minibus 4 terminal 100amp. Will that be ok to add a fuse panel to it?
Not sure about the Bennett bolt setup for the fuses as I didn’t set them up. I do have the indicator control for the tabs rather than the rocker switch if that makes any difference.
I guess this next pic is my circuit protector going to the helm. Although I wouldn’t bet my savings on it lol. It’s a 100 amp. It’s under the transom near the battery switches.

Oh ok, you are kind of limited to 100 amps. That's what I have for my fuse panel in the helm and I would trust it.

You might be getting close to the safe limit. Trim tabs are at least intermittent load and possibly autopilot too which helps the situation. I would have to see more to say for sure.

 

[wolf]

I wish my whole system is the clean and pretty looks great to me, As sea chicken say I think you will be fine its not often we have everything on the whole boat all on at once

 

[RELIC]

Looks like a few negative terminals on the fuse panel not being used.

 

[Rayvon]

Looks a hell of a lot better than my original Seasport wiring.

 

[MRWood]

Looks like a few negative terminals on the fuse panel not being used.
View attachment 124123

I noticed that as well. They must have ran some of the negatives to the bus bar above those terminals.

 

[MRWood]

Here is a breakdown of average amperage draws for common 12VDC pleasure boat electronics:
Looks like you can run quite a few things and not get up to that max 100amp range.
Trim tabs are around 20 amps
Navigation & Communication

• GPS/Chartplotter: ~0.8 – 2.0 Amps
• Radar (24 mile): ~5.0 Amps
• Depth Sounder (Color): ~3.0 Amps
• VHF Radio (Receive): ~0.5 Amps
• VHF Radio (Transmit): ~6.0 Amps
• Autopilot: ~8 – 12 Amps (when active)
• Starlink (Marine/Mini): ~2 – 3 Amps (20-40 watts)

Common Amenities & Systems

• Refrigerator/Freezer (12v): ~4.0 – 6.0 Amps (draws 120-150 Ah per day)
• Fresh Water Pump: ~4.0 Amps
• Electric Head (Macerator): ~9.0 – 20.0 Amps
• Stereo/Music System: ~2.5 – 7.0 Amps
• Cabin/Navigation Lighting: ~1.5 – 15.0 Amps (depending on number of lights)
• USB/Mobile Phone Charging: ~5.0 Amps
• Diesel Heater: ~20.0 Amps (per hour)

Heavy Duty/Safety

• Anchor Windlass (900lb): ~75.0 Amps
• Bilge Pump (500-2000 gph): ~2.0 – 8.4 Amps
• Live Well Pump: ~7.0 Amps
• Spotlight: ~8.0 Amps