Reply
 
Thread Tools Display Modes
 
Old 05-22-2020, 02:31 PM   #1
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Request for review: Electrical Diagram

Hi all!
I'm very nearly at the electrical stage with my conversion and I'm hoping some of you will take a look at my electrical diagram and give feedback. I've done a lot of residential and outdoor electrical work over the years but very little low-voltage stuff and never an RV.

What do you think? Any red flags? Anything warnings or advice?

Thanks!
Zack
Attached Images
File Type: png Wiring Diagram.png (558.0 KB, 91 views)
AzironaZack is offline   Reply With Quote
Old 05-22-2020, 03:40 PM   #2
Bus Crazy
 
Jolly Roger bus 223's Avatar
 
Join Date: Sep 2017
Location: Swansboro,NC
Posts: 1,151
Year: 86
Coachwork: Thomas
Chassis: Ford B700
Engine: 8.2
Rated Cap: 60 bodies
just bumping this to help get advice for you?
i know stuff but i dont give electrical advice except the older stuff not starting type things?
aint a sparky just a pipefitter/welder?
sorry
Jolly Roger bus 223 is offline   Reply With Quote
Old 05-22-2020, 03:57 PM   #3
Bus Nut
 
dzl_'s Avatar
 
Join Date: Jul 2019
Location: California, Bay Area
Posts: 377
A couple quick thoughts:


- I suspect you want a breaker or fuse between the starter battery and the DCC50S
- You want a breaker or switch to disconnect your PV array from the DCC50S
- I think a 50A breaker between the DCC50S and House battery is probably too small, check your documentation.
- Its generally a best practice to have a main battery fuse located as close to the battery bank as practical. Alternatively each circuit should have a fuse located close to the battery and sized for the wire it protects.
- You Blue Sea fuse block needs a fuse <125A


And a question:
What is the 'existing charger' and what is the line connecting your starting batter, your existing charger, your A/C, and your fridge?
dzl_ is offline   Reply With Quote
Old 05-22-2020, 07:51 PM   #4
Bus Nut
 
farok's Avatar
 
Join Date: Jan 2019
Posts: 366
Year: 2003
Chassis: Chevy cut-away 6-window shortie
Engine: 6.0L Gasser
Specific to that Renogy charger, be VERY careful how tight you make the nuts on the 5/16" studs. They seem to be made of really poor metal, and are hollow at the base. I was tightening one nut, and it snapped right off. It was far less pressure than I applied to the 1/4" studs on the circuit breakers I installed. Renogy was good about replacing the unit, but the quality just isn't there on those studs. It's a shame, because the charger fills a nice little gap in that I can basically add smart charging off the starter battery for $100 and no extra space beyond what I already allocated for the MPPT charger.

Chris
Attached Images
File Type: jpg IMG_20200504_165648314.jpg (206.7 KB, 9 views)
__________________
My build thread: https://www.skoolie.net/forums/f27/fi...ild-25804.html
farok is offline   Reply With Quote
Old 05-23-2020, 09:29 AM   #5
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Quote:
Originally Posted by dzl_ View Post
What is the 'existing charger' and what is the line connecting your starting batter, your existing charger, your A/C, and your fridge?
Thanks for the input, DZL. It's great to have someone else's eyes on this sort of thing.

My bus was originally a Denali National Park fire fighting transport vehicle. The service bought two and mine was their spare, so mostly it spent life sitting in a garage being started and driven every month just for operability sake.

1. The existing charger is a little trickle charger they installed to keep the starting battery topped up during storage. I intend to keep it powered with shore power while the bus is parked.

2. That line on the drawing looks continuous, but it's not. It was just intended to show power coming from the breaker panel out to the existing charger on one side and the fridge on the other. The fridge can be powered by 120v or 12v, so I was thinking about running both power sources to it, but I think it's probably just as well to run it on 12v all the time. When plugged in to shore power the DLS-55 will provide up to 55 amps as necessary for the house battery loads.

Thanks for pointing out the lack of fusing for the fuse block. Blue Sea's documentation says it's a 100A block, max, so that's how I'll fuse it.
AzironaZack is offline   Reply With Quote
Old 05-23-2020, 09:31 AM   #6
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Quote:
Originally Posted by farok View Post
Specific to that Renogy charger, be VERY careful how tight you make the nuts on the 5/16" studs.
Thanks for the heads up, Chris. That's disappointing to hear. You're absolutely right about the niche for this thing, MPPT and DC-DC charger in one is slick!
AzironaZack is offline   Reply With Quote
Old 05-23-2020, 10:06 AM   #7
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Here it is with revisions. Thanks for the input so far, anyone else care to take a peak?

Thanks for taking a look!
Attached Images
File Type: png Wiring Diagram.png (516.0 KB, 33 views)
AzironaZack is offline   Reply With Quote
Old 05-23-2020, 02:16 PM   #8
Bus Nut
 
TheHubbardBus's Avatar
 
Join Date: Apr 2019
Location: Hotzona
Posts: 934
Year: 2003
Coachwork: IC
Chassis: 3800
Engine: Navistar T444e
Rated Cap: 24
One thing that stands out is the lack of a sub-panel (& associated overcurrent protection) between your inverter & AC loads.
__________________
-Sharon & Jody
Mr Beefy Short Bus Acquisition & Build Thread
TheHubbardBus is offline   Reply With Quote
Old 05-23-2020, 04:28 PM   #9
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Quote:
Originally Posted by TheHubbardBus View Post
One thing that stands out is the lack of a sub-panel (& associated overcurrent protection) between your inverter & AC loads.
Thanks! The inverter has built-in overcurrent protection but I don't see a physical circuit breaker switch on it anywhere. I'm just running wire to three outlets inside the cabin and one outdoors. They will all on the same circuit from the inverter.

Is there such a thing as a stand-alone circuit breaker for 120V AC power that I can use? I don't want to have to cram another sub-panel into my tight space just for one breaker.
AzironaZack is offline   Reply With Quote
Old 05-23-2020, 04:39 PM   #10
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Quote:
Originally Posted by AzironaZack View Post
Is there such a thing as a stand-alone circuit breaker for 120V AC power that I can use? I don't want to have to cram another sub-panel into my tight space just for one breaker.
Found 'em! There's a whole category of stuff for this that I never knew existed. I'll post another revision.
AzironaZack is offline   Reply With Quote
Old 05-23-2020, 05:07 PM   #11
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Another revision! Thanks for the feedback thus far. More is always welcome.
Attached Images
File Type: png Wiring Diagram.png (522.5 KB, 36 views)
AzironaZack is offline   Reply With Quote
Old 05-24-2020, 07:53 AM   #12
New Member
 
Join Date: Feb 2018
Location: Philadelphia, PA
Posts: 9
Year: 1989
Coachwork: Crown
Chassis: Supercoach
Engine: Cummins 8.3L
This looks good. But I’d personally put a fuse for all loads between your battery and master cutoff switch. There should be a fuse as close to the battery as possible in case any of your loads cause catastrophic failure. We use a class T fuse for this purpose because they are very fast blow in case of overdraw situation. Best to lose a fuse than start a fire. From liking at this, I’d guess one around 300amps.

Also, curious to see your experience with the solonoid for propane. We were going to go down that route but apparently they get very hot if left on (frogotten about) for more than a couple hours.
jmiraglia is offline   Reply With Quote
Old 05-24-2020, 12:49 PM   #13
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Quote:
Originally Posted by jmiraglia View Post
There should be a fuse as close to the battery as possible in case any of your loads cause catastrophic failure.
Thanks! Sounds like good advice to me.

Quote:
Originally Posted by jmiraglia View Post
Also, curious to see your experience with the solonoid for propane. We were going to go down that route but apparently they get very hot if left on (frogotten about) for more than a couple hours.
I read similar stories about normally closed solenoid valves (which draw power constantly while open, hence the heat problems). I actually purchased a servo-valve (forgot to update the wiring diagram with it) which goes all the way open, then turns off, or all the way closed, then turns off. It doesn't draw any power at rest and doesn't generate any heat except for some negligible amount while it's changing state. The down-side of this valve is that it fails in whatever location it was last in. That said, I can always pop the top off and operate it with a wrench in an emergency.

I'm looking forward to trying it out. It's probably overkill to have an electrically operated valve on the hot water heater but my hot water heater is going to be located in a bit of a hard-to-reach spot and I don't want to muck around with a manual valve back there.
AzironaZack is offline   Reply With Quote
Old 06-03-2020, 05:27 PM   #14
Mini-Skoolie
 
Join Date: Aug 2018
Posts: 52
Year: 1955
Coachwork: Chevy
Chassis: 6700
Engine: 327
I'm curious about how the starter battery and house battery interact. On shore power, the trickle charger goes to the starter battery while the Iota charges the house battery, and the Renogy is between the two supplying solar to both batteries? Dc-Dc charger functions how in this set up? While driving, the alternator charges the starter battery and the Renogy dc-dc charges the house battery and runs the Dometic fridge? Do you have an upgraded alternator?
Bluesky is offline   Reply With Quote
Old 06-04-2020, 02:49 AM   #15
Bus Nut
 
Join Date: Feb 2018
Location: Golden Valley AZ
Posts: 589
Year: 1993
Chassis: ThomasBuilt 30'
Engine: need someone to tell me
Rated Cap: me + 1
Quote:
Originally Posted by jmiraglia View Post
This looks good. But Id personally put a fuse for all loads between your battery and master cutoff switch. There should be a fuse as close to the battery as possible in case any of your loads cause catastrophic failure. We use a class T fuse for this purpose because they are very fast blow in case of overdraw situation. Best to lose a fuse than start a fire. From liking at this, Id guess one around 300amps.

Also, curious to see your experience with the solonoid for propane. We were going to go down that route but apparently they get very hot if left on (frogotten about) for more than a couple hours.

Are you saying to move/change the fuse/breakers to before the cutoff instead of after the cutoff ? Why?
kidharris is offline   Reply With Quote
Old 06-04-2020, 03:03 AM   #16
Bus Nut
 
Join Date: Feb 2018
Location: Golden Valley AZ
Posts: 589
Year: 1993
Chassis: ThomasBuilt 30'
Engine: need someone to tell me
Rated Cap: me + 1
Quote:
Originally Posted by AzironaZack View Post
Here it is with revisions. Thanks for the input so far, anyone else care to take a peak?

Thanks for taking a look!

I am interested in this thread for my own education. What is your reasoning for not including a backup generator in your plan?


BTW, your diagram is easy to follow, but a legend with the name/model # of components, would increase its clarity and usefulness for beginners like me, especially if we tried to duplicate it. Also, a printed copy posted in your electrical service area of your schoolie would serve as a quick reminder of the layout for yourself and anyone else servicing the system later down the road.
kidharris is offline   Reply With Quote
Old 06-04-2020, 03:35 AM   #17
Bus Nut
 
dzl_'s Avatar
 
Join Date: Jul 2019
Location: California, Bay Area
Posts: 377
Quote:
Originally Posted by kidharris View Post
Are you saying to move/change the fuse/breakers to before the cutoff instead of after the cutoff ? Why?

Wasn't me who made the recommendation, but I believe what they are saying is to locate or relocate a fuse as close to the battery positive terminal as possible.


The reason why is likely because as a general rule, you want to locate fuses as close to the beginning of the circuit or the power source as possible. The further away you are, the more unprotected wiring you have.
dzl_ is offline   Reply With Quote
Old 06-04-2020, 08:57 AM   #18
Bus Crazy
 
Drew Bru's Avatar
 
Join Date: May 2016
Location: Minnehaha Co., SD
Posts: 1,039
Year: 1996
Coachwork: Amtran
Chassis: International
Engine: DT466
Rated Cap: 65
Quote:
Originally Posted by kidharris View Post
BTW, your diagram is easy to follow, but a legend with the name/model # of components, would increase its clarity and usefulness for beginners like me, especially if we tried to duplicate it. Also, a printed copy posted in your electrical service area of your schoolie would serve as a quick reminder of the layout for yourself and anyone else servicing the system later down the road.
I found this website pretty useful when I was planning our electrical system. It kinda gives you a good snapshot of what the system will look like
https://faroutride.com/interactive-wiring-diagram/
__________________
Our Build: https://dazzlingbluebus.wordpress.com/
Drew Bru is offline   Reply With Quote
Old 06-04-2020, 10:20 AM   #19
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Quote:
Originally Posted by Bluesky View Post
I'm curious about how the starter battery and house battery interact. On shore power, the trickle charger goes to the starter battery while the Iota charges the house battery, and the Renogy is between the two supplying solar to both batteries? Dc-Dc charger functions how in this set up? While driving, the alternator charges the starter battery and the Renogy dc-dc charges the house battery and runs the Dometic fridge? Do you have an upgraded alternator?
Yes, so on shore power the starter battery gets trickle charged and the Iota charges the house battery. The Renogy DC-DC charger senses the alternator running and charges the house battery from the starter battery circuit when the alternator is running. The Renogy DC-DC charger uses solar, if available, to first charge the house battery and then charge the starter battery. We don't have permanent solar, just a portable array, so most of the time that's not even connected. If we have shore power we won't have solar connected.

I don't know what alternator I have but the Dometic fridge is very low power (real world testing shows it uses around 52 watts but the specs rate it at up to around 90 watts) so a high output alternator isn't needed.
AzironaZack is offline   Reply With Quote
Old 06-04-2020, 10:25 AM   #20
Mini-Skoolie
 
Join Date: Dec 2018
Location: Tucson, AZ
Posts: 52
Year: 1991
Chassis: Wayne Lifeguard
Engine: 7.3L IDI
Rated Cap: 23,600 lb
Quote:
Originally Posted by kidharris View Post
I am interested in this thread for my own education. What is your reasoning for not including a backup generator in your plan?


BTW, your diagram is easy to follow, but a legend with the name/model # of components, would increase its clarity and usefulness for beginners like me, especially if we tried to duplicate it. Also, a printed copy posted in your electrical service area of your schoolie would serve as a quick reminder of the layout for yourself and anyone else servicing the system later down the road.
Thanks! I do plan to have a generator someday but it's not on the plan because I intend to use an extension cord from it to the shore power inlet. This allows me to avoid having a transfer switch and it makes it real easy to know where my power is coming from. If I have shore power, I'll plug that in. If I don't have shore power, I'll plug the generator into the shore power receptacle. It's a little crude, but simple.

I'm still on the fence regarding a generator at all. If I get one I want it to be quiet, but that equals big bucks and what with the current state of the world I've been trying to keep more money in my pocket.
AzironaZack is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 07:09 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
×