Please Review Noob Wiring Diagram

[maletomango]

Hello,

I have no experience with solar or electric at all. I just completed my wiring diagram (link below) for my van and I would greatly appreciate any feedback and recommendations. The battery, solar panels, and alternator isolator all came with the van when I purchased it, so I sort of planned around those.

The fuse and wiring for the battery are sized so that I can upgrade to a 200AH AGM deep cycle battery in the future if/when I need to.

A note on the Fridge- the manufacturer states that it uses 250W per 24 hrs and it is rated at 60W. A review states that on hot days it can consume a max of 25-30A (300-360W) per 24 hrs.

Power Audit: 600W usable battery capacity

(High estimations)

Fridge: 360W
Lights: 20W
Roof Fan: 100W
Computer Fan: 24W
Laptop: 100W
Phone: 10W
=524W

Wiring Diagram

https://docs.google.com/drawings/d/1RYJO1x1fIQf-m7oi0D9RJLwWDaHvReq0W2P31__D8iA/edit?usp=sharing

Parts List

Parts List Electric System

docs.google.com

 

[John Frum]

I'm concerned about the keyline charger circuit

4 awg upstream and downstream​

140 amp fuse upstream​

150 amp fuse downsream​

20 feet(assuming 40 feet round trip)​

How much current are you really expecting on this circuit?
How a lead acid house battery pull anything like those kind of amps?
According to this calculator in order to get 3% voltage given 13 volts, 40 feet and 140 amps you need 3/0 awg wire.

Interactive Wire Size Calculator

Battery Chargers, Inverters, Solar Components, and Wiring Supplies for Boats, RVs, and Off-Grid Applications.

baymarinesupply.com

Unless the charger has voltage sense leads I suggest you put the charger close to the house battery to minimize voltage drop where it counts.
The supply side can compensate the charge side can't unless it knows the voltage at the battery terminals.

 

[maletomango]

Hey there,

Thanks for your feedback! I understand your concern. The keyline charger/isolator was one of the things that was installed when I got my van. It looks like the kit for the isolator came with 7AWG, but the previous owners opted for 4AWG. The entire circuit is max 20 feet. I found the following information on the manufacturer website:

• ZERO VOLTAGE DROP: Forget the traditional diode relays and so-called "solid state" devices that can rob you of almost 2 amps of output power! The KeyLine Dual Battery Isolator is the only unit designed with cutting edge programming to deliver optimum performance - with ZERO sacrifice. This compact battery isolator was built ultra-small (2.6" x 2.6" x 2") to fit almost anywhere! A perfect fit under the hood to get close to your dual batteries.
• VOLTAGE SENSITIVE RELAY: The KeyLine Automatic 140 Amp Dual Battery Isolator is all you need to charge Two Battery Systems. Voltage Sensitive Relay (VSR) cuts in at 13.3 volts and cuts out at 12.8 volts to ensure your primary battery is always charged and ready to start your vehicle. It's like having two separate power sources for each battery while only having one alternator!

12V 140 Amp Dual Battery Isolator & Full Size Automobile wiring kit

ZERO VOLTAGE DROP: Forget the traditional diode relays and so-called "solid state" devices that can rob you of almost 2 amps of output power! The KeyLine Dual Battery Isolator is the only unit designed with cutting edge programming to deliver optimum performance - with ZERO sacrifice. This...

www.keylinechargers.com

It is installed next to the starter battery as it, but I am sure I could move it inside the cargo space near the house battery if that will work better. What do you think?

 

[John Frum]

Hey there,

Thanks for your feedback! I understand your concern. The keyline charger/isolator was one of the things that was installed when I got my van. It looks like the kit for the isolator came with 7AWG, but the previous owners opted for 4AWG. The entire circuit is max 20 feet. I found the following information on the manufacturer website:

• ZERO VOLTAGE DROP: Forget the traditional diode relays and so-called "solid state" devices that can rob you of almost 2 amps of output power! The KeyLine Dual Battery Isolator is the only unit designed with cutting edge programming to deliver optimum performance - with ZERO sacrifice. This compact battery isolator was built ultra-small (2.6" x 2.6" x 2") to fit almost anywhere! A perfect fit under the hood to get close to your dual batteries.
• VOLTAGE SENSITIVE RELAY: The KeyLine Automatic 140 Amp Dual Battery Isolator is all you need to charge Two Battery Systems. Voltage Sensitive Relay (VSR) cuts in at 13.3 volts and cuts out at 12.8 volts to ensure your primary battery is always charged and ready to start your vehicle. It's like having two separate power sources for each battery while only having one alternator!

12V 140 Amp Dual Battery Isolator & Full Size Automobile wiring kit

ZERO VOLTAGE DROP: Forget the traditional diode relays and so-called "solid state" devices that can rob you of almost 2 amps of output power! The KeyLine Dual Battery Isolator is the only unit designed with cutting edge programming to deliver optimum performance - with ZERO sacrifice. This...

www.keylinechargers.com

It is installed next to the starter battery as it, but I am sure I could move it inside the cargo space near the house battery if that will work better. What do you think?

Just to be clear voltage drop is based on round trip circuit length.
I see from the link that its much more an isolator and much less a charger.
Based on that I now think its location doesn't matter.

 

[mikefitz]

keyline charger is I think a voltage sensitive combining relay rated at140amps. With the alternator feeding via this to the house battery of 100Ah expect around 20 amps with an initial surge of perhaps 50 amps at the most, 4 awg is fine for this. I would fuse at 100 amps.
Cable from the house battery is not shown, suggest 4 awg and the main battery fuse at 150 amps

fridge pulls high current on start and is sensitive to cable volt drops , cable 10awg fused at 15 amps

100Ah sealed led acid is somewhat a low capacity for the system if you intend to run the inverter at full power. Consider a second in parallel.

With a single battery you only have 50Ah usable if you want it to give reasonable service with a maximum continuous draw of 20 amps.

With an off grid system and poor solar conditions the fridge will eat up the Ah.

Mike

 

[maletomango]

keyline charger is I think a voltage sensitive combining relay rated at140amps. With the alternator feeding via this to the house battery of 100Ah expect around 20 amps with an initial surge of perhaps 50 amps at the most, 4 awg is fine for this. I would fuse at 100 amps.
Cable from the house battery is not shown, suggest 4 awg and the main battery fuse at 150 amps

fridge pulls high current on start and is sensitive to cable volt drops , cable 10awg fused at 15 amps

100Ah sealed led acid is somewhat a low capacity for the system if you intend to run the inverter at full power. Consider a second in parallel.

With a single battery you only have 50Ah usable if you want it to give reasonable service with a maximum continuous draw of 20 amps.

With an off grid system and poor solar conditions the fridge will eat up the Ah.

Mike

Hey Mike,

Great input! You are right that the 50Ah capacity I currently have is cutting it very close. I have sized my wire (2/0awg) from the house battery to the bus bar and the house battery terminal fuse (225A) so that I can upgrade to a 200Ah battery bank in the future. I haven't had a chance to test the power consumption of the fridge, but I am prepared to upgrade my battery bank right away if it is worse than anticipated.

As far as the fridge cable goes, I am not sure how to use a different wire size from the original cable (16awg, 11'). Should I connect the 10awg wires directly to the male outlet prongs on the fridge?

Here is the type of power cable it came with.

Amazon.com: SolarEnz 12V/24V Fridge Power Cord DC Freezer Cable For Car Refrigerator Car Fridge Freezer Replacement for Alicool,COSTAY,AR,Ausranv,Portable Car Refrigerator Fridge : Automotive

Amazon.com: SolarEnz 12V/24V Fridge Power Cord DC Freezer Cable For Car Refrigerator Car Fridge Freezer Replacement for Alicool,COSTAY,AR,Ausranv,Portable Car Refrigerator Fridge : Automotive

www.amazon.com

Thank you!