solarJunky
New Member
Just make a new shore power at front of rig closet to the victron unit... if possible... after disconnect of old one...
What's the best way to splice AC in an RV?
- Thread starter chaostactics
- Start date
chaostactics
New Member
Maybe in the future. I figured out something for now.
HighDesertOffgrid
Solar Addict
- Joined
- Sep 15, 2022
- Messages
- 628
Round trip=Non-standard verbiage for an AC electrician. Voltage drop calculated by the run (half the round trip). However, All roads do lead to Rome.
RoadTurtle
Solar Enthusiast
- Joined
- Mar 30, 2022
- Messages
- 365
Could you please share your solution? It's the next phase of my install.
chaostactics
New Member
Dinkle Assembly DK6N 10 Gang Box Connector DIN Rail Terminal Blocks, 8-20 AWG, 50 Amp, 600 Volt Separate Circuits https://a.co/d/08PNI04
Others have mentioned putting in another shore power outlet and I may do that in the future.
RoadTurtle
Solar Enthusiast
- Joined
- Mar 30, 2022
- Messages
- 365
I may be a little slow, but how is the terminal block fixing the issue of running wires to the front and then back again?
I did put a connector on the front of my trailer and wired it into the gen ready ATS circuit. It's wired as 50a and was put there in case I ever needed to plug in the front, run the generator while in the bed of the truck, and an inlet source for my original inverter (50a plug). Problem with planning to use this as the main inlet, the rear is still usable, and If I do need to plug in, the multiplus would have to be shut off to avoid a potential system conflict. Maybe I'm over thinking this one a lot.
Last edited:
chaostactics
New Member
My only goal was connecting the existing Romex that was coming from the shore power inlet to my main panel. Now I'm connecting the shore power to the victron directly via a run of 10/3 that I installed from the front compartment to behind the main panel. My shore power inlet was on the back of the trailer and my victron gear on the front end.
PlanetExcellent
New Member
- Joined
- Sep 16, 2021
- Messages
- 43
I had the same issue -- inverter up front, shore power coming from far side to distro panel. I used 10/3 cable, and used a 30 amp plug set to connect the shore power to the new cable leading to the inverter. Then another length of 10/3 from inverter back to distro panel. Seems to be working great.
RF_Burns
New Member
I'm a bit late to the party here.. but, with your Inverter/charger you want to install it as close to your batteries as possible. The reason being is the low voltage DC side will see at least 10x the current of the AC side. Also the output of the charger is regulated at the DC side while its AC input can vary due to losses and power line fluctuations.
When using the inverter to operate say a microwave at 1200 watts, the input from the batteries might be 1500w / 12V = 125 Amps. This can cause a significant voltage drop in the wiring from the battery.
If you have LiFePO4 batteries, they can be charged at a much higher current than Lead-Acid. But the charge voltage at the battery must be monitored closely to properly charge the battery. I have only 3ft of #4 wire on each side of my LFP batteries, yet I still see about 200mV of voltage drop between the charger terminals and the battery terminals at 50A charge rate. The is a significant voltage difference when charging LFP batteries. The charger should be sampling the battery voltage right at the battery terminals, not inside the charger (remote voltage sense), but I haven't seen a RV service charger offer this feature.
When using the inverter to operate say a microwave at 1200 watts, the input from the batteries might be 1500w / 12V = 125 Amps. This can cause a significant voltage drop in the wiring from the battery.
If you have LiFePO4 batteries, they can be charged at a much higher current than Lead-Acid. But the charge voltage at the battery must be monitored closely to properly charge the battery. I have only 3ft of #4 wire on each side of my LFP batteries, yet I still see about 200mV of voltage drop between the charger terminals and the battery terminals at 50A charge rate. The is a significant voltage difference when charging LFP batteries. The charger should be sampling the battery voltage right at the battery terminals, not inside the charger (remote voltage sense), but I haven't seen a RV service charger offer this feature.
Vigo
Solar Addict
So, since nobody ever directly addressed this..
Voltage drop over wire runs DOES EXIST with both AC and DC. The difference is that the amount of voltage drop is calculated slightly differently for AC vs DC. In some cases this means an online calculator could return with a slightly different voltage drop number, or ask for 1 size up or down on the wire size, if you calculate the same conditions in AC and DC. But voltage drop is very real in both cases, and the difference in most common residential scenarios is very small.
When you get into vast distances and different frequencies than 60hz that can change, but for DIY/residential projects there is very little difference between the voltage drop of the same exact circuit given AC or DC. No more than one wire size or a couple percentage points difference, generally.
Last edited:
RF_Burns
New Member
Vigo is correct, there is losses in both AC and DC circuits. What is critical to remember when wiring Inverters is the DC side has approximately 10 times the current flow at 1/10 the voltage. I plugged in some numbers into a voltage loss calculator considering a purely resistive 1200 watt load (like a coffee maker). I used nominal 120VAC and 12VDC and not getting into additional losses from connectors, battery internal resistance etc. Also not considering inverter losses which require a higher DC input power.
On the AC side, 20 feet of #12 wire: 1200 w = 10A current flow
Voltage drop: 1.24
Voltage drop percentage: 1.04% (very acceptable 1% voltage loss)
Voltage at the end: 118.76V
On the DC side, 20 feet of #4 wire: 1200 w = 100A
Voltage drop: 1.24 (same voltage drop as above)
Voltage drop percentage: 10.36% (Wow, 10% voltage loss)
Voltage at the end: 10.76V (inverter will likely be alarming low voltage)
Inverter moved closer, only 4 feet of #4 wire
Voltage drop: 0.12 (much lower voltage lost)
Voltage drop percentage: 1.04% (as a percentage,voltage loss is now the same as 120V side)
Voltage at the end: 11.88V
So the moral is, when installing inverters keep your voltage drop as low as possible by using large conductors and keeping the conductors as short as possible. The AC side which is carrying about 1/10 the current is easier to control the voltage losses with longer runs.
On the AC side, 20 feet of #12 wire: 1200 w = 10A current flow
Voltage drop: 1.24
Voltage drop percentage: 1.04% (very acceptable 1% voltage loss)
Voltage at the end: 118.76V
On the DC side, 20 feet of #4 wire: 1200 w = 100A
Voltage drop: 1.24 (same voltage drop as above)
Voltage drop percentage: 10.36% (Wow, 10% voltage loss)
Voltage at the end: 10.76V (inverter will likely be alarming low voltage)
Inverter moved closer, only 4 feet of #4 wire
Voltage drop: 0.12 (much lower voltage lost)
Voltage drop percentage: 1.04% (as a percentage,voltage loss is now the same as 120V side)
Voltage at the end: 11.88V
So the moral is, when installing inverters keep your voltage drop as low as possible by using large conductors and keeping the conductors as short as possible. The AC side which is carrying about 1/10 the current is easier to control the voltage losses with longer runs.
Camping2023
New Member
I left my motorhome a/c electrical system alone, did nothing to it. I wired my d/c (12 volt) system to my load connection on my solar controler. Then I just plug in my Motorhome shore power into my inverter. I did leave my converter/ charger hooked up, but I had to turn off the a/c power breaker to keep it from back feeding. If I ever decide to plug into shore power i'll just turn off the solar system and turn on converter before pluging in. My inverter is mounted in side of the electrical cord storage area for easy plug in and to get inverter. What give me I idea to plug into my solar system was my generator was the same way you just plug the shore power into a outlet coming from it.
Similar threads
