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Vycan · 05-07-2016, 11:18 PM

Ordered a bunch of magnum stuff. Forgot to get the battery temperature sensor.

The new inverted is much bigger than my old one that sits behind the kick board. I am planning on putting the new one in the bottom of my forward cabinet, and removing the bottom shelf to replace with a louvered vent. Sadly, when I went to remove the small cabinet it seemed fastened to the dash. I verified no screws are present, but it is held fast. I was going to remove it, place the inverter on the floor, slide it towards the front, then slide the cabinet until both were situated to ensure minimal impact to the cabinet. Because I cannot remove the cabinet I must modify the cabinet to allow reciept of the inverter. Looks like I will have to sawzall the bottom cross piece flush with the sides of the drawer above. This will allow me to slide the inverted in through the bottom. Then the wiring fun begins.

Once the new inverter/charger is in and hooked up, I will remove the old converter charger and put the solar charge controller in its place.

Kota · 05-08-2016, 05:41 AM

There some access able screws in the back base of the center cabinet. It comes out easily after you find then.

Vycan · 05-08-2016, 10:26 AM

Kota,

I removed all the screws at the base. The base will slide forward, but the dash comes with it. All the screws in the top compartment pointing towards the front have been removed. The ABS of the dash is is acting like it is glued to the cabinet. Will try again today.

SebasSF · 05-08-2016, 12:04 PM

I took mine out as well...when all the nasty long screws are removed, just lift up a little on the dashboard to take the pressure off and it will slide out...work it out one side at a time if it's tight.

I was thinking of using the same location.

The next challenge I found- the wires going to the converter run back under the dash towards the drivers side and I have not been able to track them. I think the white is just grounded to the frame somewhere. They are also not large enough to power the inverter, so it may be best to simply cap them off, run a new heavy gauge wire directly to the battery terminals.

The AC romex also runs under the dash towards the drivers side. There is probably enough wire to remove the plug and pull it back and wire it directly to the input terminal on the inverter. Figuring out how to wire the inverter output back to the AC breaker panel will be fun.

Vycan · 05-08-2016, 04:12 PM

So I was not crazy, there were three screws in the cabinet that held it to the dash without access anywhere. I used a pry bar to separate them from the ABS plastic, and replaced after. Right now the inverter is placed.

For wiring, the magnum has an automatic transfer switch built in, so I planned to disconnect the shore power from the ATS at the rear of the coach, run the line up to the front, through the access in the hood, then run it back from the inverter to the ATS in the back. Only concern I have is what happens when the inverter is providing 120VAC and the generator kicks on. I also considered disconnecting from the downstream side of the ATS in the rear, running the power first to the inverter, then to the downstream line. Thoughts?

lewster · 05-08-2016, 05:32 PM

Vycan,

Magnum includes the battery temp sensor in every new inverter/charger. It should have been packaged with the terminal covers and AC access panel.

Lew Farber
RVIA/RVDA Nationally Certified Master Tech
ABYC Certified Master Marine Electrician
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center*AMS Lithium Batteries
Lifeline AGM Batteries**Magnum Inverters***Victron Energy Components
541-490-6357

Vycan · 05-08-2016, 05:36 PM

Lew,

It sure was, I found it this morning when I was fitting the inverter, forgot to update. Great catch!

SebasSF · 05-08-2016, 08:36 PM

You have a 60 amp transfer switch, so you could run direct from your shore power input. Keep wire size in mind if you do it this way as you will be running both AC units through the inverter- or would you? The wire between your batteries should be the same size as your inverter DC wire as well.
I don't have a proper single line diagram of my 50 amp service wiring, and have not figured this out yet. I have my inverter wired up as a charger so far...

lewster · 05-09-2016, 07:25 AM

Quote:

Originally Posted by Vycan

So I was not crazy, there were three screws in the cabinet that held it to the dash without access anywhere. I used a pry bar to separate them from the ABS plastic, and replaced after. Right now the inverter is placed.

For wiring, the magnum has an automatic transfer switch built in, so I planned to disconnect the shore power from the ATS at the rear of the coach, run the line up to the front, through the access in the hood, then run it back from the inverter to the ATS in the back. Only concern I have is what happens when the inverter is providing 120VAC and the generator kicks on. I also considered disconnecting from the downstream side of the ATS in the rear, running the power first to the inverter, then to the downstream line. Thoughts?

Vican,

That's not exactly how it should be done. The inverter 120VAC input should come directly from a dedicated 30 amp breaker in your main panel. The inverter's output should then go into a sub panel containing all of the circuits that you want to operate from the inverter while off-grid. The transfer switch in the Magnum is designed to either 'pass-thru' 120VAC into the sub panel when shore power is present or provide 120VAC to the sub panel circuits when using the inverter/battery combination when off-grid.

The 120VAC input to your main panel should be the same; from your coach transfer switch! This is where it selects either shore input OR generator. This should not be changed.

PM me if you have more specific questions.

You will also find some good working block diagrams in the Magnum manual.

Vycan · 05-09-2016, 06:22 PM

So my coach has two ATS's both are 30amp (one main, and one rear AC) and I suspect it was done that way because it was wired for 30amp service. Understanding it should have a dedicated 30amp surge protector, but the ATS is for 30amp service, and I have a surge protector at the plug in to external power, that is why I am running the electric this way.

SebasSF · 05-09-2016, 11:41 PM

Interesting, I think I have a 50 amp service, I have three ATS's in the back and I think I can run both AC units at one time from shore power. ..I don't have a selector switch. Luckily you have an accurate wiring diagram. I think you have your wiring figured out correctly. If you running the inverter and the generator kicks on automatically your wiring would work IF the inverter switched off and went back to transfer/charge mode. Call Magnum.

lewster · 05-10-2016, 12:51 PM

Interesting!

On most 50 amp service RVs that I have worked on, there is a single 50 amp transfer switch compromised of a ground, neutral and 2 hot legs a 120 VAC.

Don't know why Airstream felt the need for 3 transfer switches, as the sole function of the transfer switch us to isolate the shore power from generator power so they both can't reach your breaker box simultaneously.

But then, Airstream seems to go their own way when it comes to electricity anyway.

Lew Farber
RVIA/RVDA Nationally Certified Master Tech
ABYC Certified Master Marine Electrician
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center*AMS Lithium Batteries
Lifeline AGM Batteries**Magnum Inverters***Victron Energy Components
541-490-635

Vycan · 05-29-2016, 09:24 PM

Actually hooked up the inverter/charger this weekend. Ran the AC as planned from the automatic transfer switch to the inverter, and back for the coach. The 3/000 wire for the 3ft of travel to the batteries was an absolute PITA! Also re-did the series cable in 3/000 so the entire system can withstand the draw of the inverter.

In the pictures are the evolution of placements. In sequence: 1. AC in, with position of access holes and grommets in place. 2. AC in with Shunt mounted. 3. AC in with AC out, DC cables ran, removed shunt and replaced with battery monitor. Last shows the inverter in its resting place with shunt in the top right.

Also installed but w/o pics: 1. Magnum remote, 2. Solar charge controller. The solar charge controller is in the position of the old charger, and is at a skewed angle due to me not wanting to drill any more holes in the compartment.

Essentially used the left mounting bar for the charger anchored it only on the bottom, and rotated about that bottom mounting point until the top came close enough to the upper right anchor to place the solar controller mounting block. Then placed the solar charge controller on the block. Also used the bottom anchor of the left mounting bar for the surface mount 30A circuit breaker. Looks a bit whonky, but all is secure and grounded. Will post pics when i get a chance.

The Solar charge controller it not connected. As with the inverter, I like to place things and think about the install, running cables, and determine if what "seemed like a good idea at the time" will actually be a good idea.

Still to do:
1. Mount 500W of solar panels on the roof
2. Wire the solar connections through the coach
3. Make a junction box for the solar power
4. Connect the solar to the MPPT Solar Charge Controller
5. Connect the Solar Charge Controller to the batteries

Once done my summer electric upgrades will be complete. Then off to Newfoundland!

SebasSF · 05-30-2016, 09:33 PM

Looking good! So you ran two new AC lines front to back? What wire did you use?
If I understand correctly what you did- you took out the wires that ran from the coach side of the transfer switch to the AC panel and ran new wires from the terminals to the inverter, then back down from the inverter and tied into the wires that run to the AC panel? Sounds like a solid plan.

I need to spend some more time figuring my system out. My MS 2012 is not rated for 50 amps, but I suspect this is not a problem because I think one of the legs probably goes directly to one of the AC units. Do you have a switch for front or rear AC when running on shore power?

Vycan · 05-31-2016, 03:25 AM

Sebas, I used 90ft of 8/3 wire.

Your description of the run is correct.

I have a switch for the two AC's.

Vycan · 06-04-2016, 07:38 AM

This next weekend is a four day weekend, and I am going to bring DD to the house and verify my plan for cable routing will work for the solar. As a recap:

I plan to use the fantastic vent as the input. I will place the MC4 connectors on the outside and run the cable into them from the inside so it is a simple connect and disconnect on the roof for each panel. I have measured the projected run as 25ft (allowing for 12" of play on each side of the run), I could run the panels in pairs on the 10AWG wire I have planned, but could double up each panel for less runs. Current plan with five panels is 10 holes in the fantastic vent. If I ran the three I could do six holes.

So on to the questions:
1. Do I have to run the (-) to the battery or can I ground it on the chassis? By electric theory I could ground to chassis, so what are the issues with this?
2. There is clearance at the black tank vent around the PVC pipe to enter there. I could also enter at the fridge vent. What is the recommended course of action?
3. I currently have a 30A MPPT solar charge controller. At full sun each panel creates 5.5A for a total of 27.5A. As I understand I can add a sixth which would put me at 33A, at 3A over the MPPT max. However in partly cloudy conditions it would give me more Amps to the batteries but less than the max rating. What would be the concerns to doing the 6x 100W panels at 5.5amps with a 30A MPPT controller?

SebasSF · 06-04-2016, 09:41 AM

I would defiantly run the pos and neg solar wires to the controller...don't ground to chassis.
What is the voltage rating on the controller? You could run all the panels in series up to the max voltage rating for the controller on one #10 wire if it can take the voltage. What happens to the controller if you go over on amp rating depends on the device, but typically it is better to keep volts as high as possible and amps lower...it's the amps that create heat. This is advice from my residential solar experience.

SebasSF · 06-04-2016, 09:52 AM

FYI, on my old Excella there was a small solar panel...factory installed I think that was tied in on the terminals in the back of the fridge. I think the fridge wire and circuit are a # 10 or even an 8.

lewster · 06-04-2016, 12:24 PM

Just remember that every wire and connection created resistance and voltage drop. Longer cable runs require higher voltage or heavier cable sizes.

All connections should be kept to a minimum for best results.

This is why we connect directly to the batteries in our solar installations.

Lew Farber
RVIA/RVDA Nationally Certified Master Tech
ABYC Certified Master Marine Electrician
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center*AMS Lithium Batteries
Lifeline AGM Batteries**Magnum Inverters***Victron Energy Components
541-490-6357

Vycan · 06-04-2016, 05:12 PM

SebasSF, great point! Chassis ground would completely bypass the controller, since the battery is a chassis ground. Thanks for the catch!

Lewster, you bring up a great point WRT number of connections and voltage drop. Looks like the clean and direct connections of each panel will work best.

Current routing is the 3' factory line from the panel to the rooftop connection at the fantastic fan which will add 0-3' depending on which solar cell by placement. Each panel will have a (+) and (-) line at 10 AWG for 20' to the junction box. From the junction box to the controller I will have a 6-8" run of 4 AWG, and from the controller to the battery I will have a 3' run of 4 AWG.

These are the panels I am using. Optimal current is 5.29A, planning based on 5.5A

Any feedback on the routing?