Sprinter-Forum    
 

Go Back   Sprinter-Forum > Sprinter-Based RV's & Conversions > Sprinter RV's & Conversions Talk

Sprinter RV's & Conversions Talk Common features found in Sprinter RV's and Conversions.


 
Thread Tools Display Modes
Old 09-23-2016, 09:06 AM   #11
Oldfartt
 
Oldfartt's Avatar
 
Join Date: Nov 2006
Location: Nelson New Zealand
Posts: 882
Thanks: 147
Thanked 433 Times in 298 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

1. The maxi fuse shown on the latest drawing can be replaced with one on the pre-fuse block as shown in the MB file pages 13 and 14 which connects to the ACR from the engine battery. The fuse should be rated at around 80 amps. You do not have to buy a 500A ACR. You do not need the fuse on the right of the ACR as the circuit is protected by the fuse nearest to the engine battery. This is the better place for the protection fuse is at the engine battery pre-fuse block.
2. It is best to cable for the capability of your inverter as you may not know what uses it may be put in the future. For best performance and efficiency the cables need to be as short as possible and with the least resistance in the circuit. Each connection to terminals, fuse-holders, fuse ,etc, add to the circuit resistance.
3. The inverter does not need to be hard wired, I am only suggesting it as an option.
4. You can do whatever you want. If you want to know how much is going into and out of the battery which includes all of the items connected to the battery then you will need a shunt.
5. You have all the elements to do the job properly, why not use them. The battery monitor is capable of measuring all the current so long as it is wired as I have suggested in my first post.
Move the ground point to the bottom of the shunt.
6. Move the wire currently shown at the bottom of the shunt to the -Ve bus bar
7. The LED fuses can be 10Amp each
8. The Maxi Fan fuse can be 10Amp
9. The Maxi fuse from the house battery to the fuse panel can be 40Amp.

Cheers

Ross
__________________
2011 315 Mercedes extra long Cargo Van converted to RV
2000 313 Mercedes Sprinter Motorhome (Sold)
Oldfartt is offline   Reply With Quote
The Following User Says Thank You to Oldfartt For This Useful Post:
scooter1942 (09-23-2016)
Old 09-23-2016, 09:49 PM   #12
scooter1942
 
Join Date: Jul 2016
Location: Dallas, TX
Posts: 36
Thanks: 12
Thanked 43 Times in 11 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

Great info. Many many thanks.

Here's the latest variation....if I'm understanding that Oldfartt correctly!:thumbs: Admittedly I have some confusion regarding the position/relationship of the shunt, neg bus and ground but hopefully I've followed instructions.
Attached Files
File Type: pdf My-schematic-v.1-3-2.pdf (51.6 KB, 54 views)
scooter1942 is offline   Reply With Quote
Old 09-23-2016, 10:15 PM   #13
MsNomer
 
Join Date: Feb 2015
Posts: 361
Thanks: 11
Thanked 217 Times in 134 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

Don't assume you will require the inverter for camera and computer charging. There may be 12v chargers available. We have them for cameras and computers.
MsNomer is offline   Reply With Quote
Old 09-23-2016, 11:02 PM   #14
Oldfartt
 
Oldfartt's Avatar
 
Join Date: Nov 2006
Location: Nelson New Zealand
Posts: 882
Thanks: 147
Thanked 433 Times in 298 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

Hi Scooter,

Yes very nearly perfect!

The wire drawn from the solar controller to the MT 50 Tracer meter is actually an ethernet type cable and is all that is required to run the meter. The line shown from the meter to the -ve buss can be removed.

Now I have overlooked an important omission. The diagram shows the shunt correctly but there is nothing for the shunt to be used by. There needs to be a battery monitor for the shunt to provide the DC current information. I suggest that you include a Votronic 1262.
The insructions will show you exactly how to wire it. You need to provide a voltage feed ( low current) from the engine battery, the house battery and the current sense wires from the shunt. Then it will show the most important information on the state of charge of the house battery. This gives peace of mind when travelling.

Cheers

Ross
Attached Files
File Type: pdf Votronic LCD-Batterie-Computer S ab 04-2013_e (2).pdf (799.4 KB, 44 views)
__________________
2011 315 Mercedes extra long Cargo Van converted to RV
2000 313 Mercedes Sprinter Motorhome (Sold)
Oldfartt is offline   Reply With Quote
Old 09-24-2016, 04:29 AM   #15
autostaretx
Erratic Member
 
autostaretx's Avatar
 
Join Date: Sep 2006
Location: Seattle
Posts: 17,395
Thanks: 3,046
Thanked 7,854 Times in 5,729 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

Inexpensive inverters like that Bestek produce "modified sine wave" (actually interrupted square waves) on their 110 vac outputs.
Many devices (such as power tool chargers) do not like that waveform.

Although the USB sockets will be great for your cellphones (etc), the 25 amps (or double that, since their product info says it'll do 700 watts for a short period) is pushing it for cigarette sockets. When you buy your sockets, verify that they can handle that current (the T1N Sprinter's ashtray socket would melt... except it's not fused that high (they still melt)).

--dick
__________________
2005 T1N 118" Freightliner 2500 Passenger Wagon (2.7L, 15" tires, standard (short) roof)
Get YOUR Sprinter's full configuration datacard by entering your VIN to https://www.datamb.com/
http://diysprinter.co.uk/reference <-- lots of service documentation, Thanks to Jens Moller and Arnie_Oli
((as always: this post may go through a couple of post-posting edits... so maybe give it ten minutes before commenting))
autostaretx is offline   Reply With Quote
Old 09-24-2016, 02:11 PM   #16
scooter1942
 
Join Date: Jul 2016
Location: Dallas, TX
Posts: 36
Thanks: 12
Thanked 43 Times in 11 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

Ross,

Good catch on removing the ground wire from the MT-50. However, that got me to researching all of the functions of the MT-50 and it appears to provide battery voltage, SOC, etc. though interface appears to be cumbersome. With that said, would it be redundant to have a battery monitor?

Could I simply use something like this?: https://www.bluesea.com/products/173...D_DC_Voltmeter

And I'm confused about the wiring. Reading the Votronic instructions, they clearly state that nothing should be placed between the - battery post and the shunt. So what do I do with my negative buss? And if I need to wire leads back to my battery bank and the starter battery...now I wonder if it is more trouble than necessary...especially if the MT-50 gives me that info?

I've done some research on my USB and 12V plugs and have changed the fuses to match their max/recommended load. Which is only 15A for the 12V plug, but again the Bestek only works from a 12V cigarette lighter plug and cannot be wired any other way...unless I start cutting.

Next I started wondering about what the shunt, + buss and - buss should be rated for? 100A, 150A, 250?

Here's the latest iteration of the schematic
Attached Files
File Type: pdf My-schematic-v.1-4-2.pdf (51.4 KB, 44 views)
scooter1942 is offline   Reply With Quote
Old 09-24-2016, 03:43 PM   #17
NBB
 
Join Date: Sep 2009
Posts: 1,331
Thanks: 93
Thanked 439 Times in 301 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

You're opening a worm hole and getting sucked in. Your first schematic looked better than the latest, IMO. You need to think and do the math. If you think advice on this forum combined with marketing literature is going to solve your problem, you're headed for a real mess. Think - a shunt measures current. You need to monitor current in and out of your battery, no shortcuts. Trace the current.

This is how I handled my (-) side. Current comes in through the body, 0000 cable through 2 ground lugs, cut-off switch (important!), shunt, negative battery cables, battery, out the plus side of battery to fuses, through appliances chargers and what-not, and back to the body.

http://sprinter-source.com/forum/sho...4&postcount=67

The bus is just for battery cables. Create another (-) bus elsewhere, probably near the fuse box, for (-) returns from various appliances, battery charger included.

You want a battery monitor. Measuring voltage alone tells you nothing, you need the current.
NBB is offline   Reply With Quote
Old 09-24-2016, 08:55 PM   #18
GeorgeRa
2013 Sprinter DIY 144WB
 
GeorgeRa's Avatar
 
Join Date: Feb 2012
Location: Portland, OR
Posts: 4,317
Thanks: 1,213
Thanked 2,415 Times in 1,560 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

I am repeating the previous post to some degree in perhaps in simplified form.

Current flowing through the measuring shunt generates a voltage which accurately reflects flowing through current and this voltage is accurately measured by the battery monitor. Different polarity of the voltage will tell the monitor if current flows into the battery or out of the battery.

To connect this measuring shunt correctly all current flow between the negative battery post and consuming devices and charges must flow through it. Your last diagram is not showing it, so make sure:

Negative battery post > measuring shunt > loads/charges

George.
__________________
George.

https://goo.gl/photos/2NCR3teXLSwNYSwN8

Last edited by GeorgeRa; 09-25-2016 at 05:51 AM.
GeorgeRa is offline   Reply With Quote
Old 09-24-2016, 09:28 PM   #19
outbound
06/2500/140
 
Join Date: Jan 2016
Location: SLC
Posts: 885
Thanks: 1,046
Thanked 296 Times in 222 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

Quote:
Originally Posted by scooter1942 View Post
My goals:
-I want to have my alternator charge my house batteries while driving.
-I want to have my solar charge my batteries while stationary. ...
dont have the time at the moment to delve deep here - but IMHO the best way to have the eng-alt throw charge into the housebank is the way its typically done on boats:

with a '1-2-both' switch

now.. a lot of people might tell you that an 'isolator' is a better way to go, but introduces quite a few implications (that i dont have time to get into)

while the best part of a simple 1-2-both switch is that as long as the interconnection conductors are properly sized (for the max output of the eng-alt plus voltage drop to the batteries; ie: not less than #2)?

if your engine cranking battery craps out, all you need to do is put the switch to BOTH and voila!
you have almost endless cranking capacity (since the housebank will typically be much larger than the crank batt)

one just has to pay attention to what position one has the switch, when in discharge mode.

just my .02
(and i've been a DC electrical specialist since mom bought me a trainset for xmas when i was 14 ;)
outbound is offline   Reply With Quote
Old 09-24-2016, 11:51 PM   #20
NBB
 
Join Date: Sep 2009
Posts: 1,331
Thanks: 93
Thanked 439 Times in 301 Posts
Default Re: Another Electrical Thread: Don't let me catch it on Fire!

Quote:
Originally Posted by outbound View Post
1-2-both' switch
No production RV on the planet does this. Nobody wants to dick around with some switch several times a day, only to be forgotten at some point.

If you want to "jump" the start battery, insert a manual switch to apply voltage to the isolator - done.

The most common way to combine solar and an isolotor - is to just combine them. Wire each per the instructions.

Solar is just like every other widget you hook into your system - it just happens to push current rather than pull it. Hook the controller up to your fuse box next to the lights, the fridge, whatever. Size your wires as you size all the others. You're done. Few on this forum have demonstrated the skill and experience to consider it beyond that, and they do not need to.
NBB is offline   Reply With Quote

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

Forum Jump



All times are GMT. The time now is 02:40 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.