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Wiring a 2nd inverter

Yahoo Message Number: 88826
I have a few electronic components that would benefit from a true sine wave inverter. None of them pull very many amps. Rather than spending a lot of $$$ to replace the existing Freedom 25, I decided to just add a smaller Xantrex inverter. On my coach, the house batteries are in the rear and the 12v dc panel is near the front bay. There are 2/0 gauge wires that run from one location to the other. This is where I'd like to locate the second inverter. I'll probably use some very short 2 or 4 gauge wire to hook it up. There is a ground buss down in that bay that has a ton of green ground wires going to it. Is this where I should connect the negative terminal of the inverter. Also, there is an additional chassis ground wire for the inverter. What should I connect this to? When I talked to the tech guy at Xantrex, he said that the 200 amp circuit breaker from the house batteries would suffice and that I did not need to add a separate fuse, does that sound right?

Jim

99' Magna #5629

Re: Wiring a 2nd inverter

Reply #1 –
Yahoo Message Number: 88831
Jim,

You had me until you talked about fusing 2 or 4 gauge wire with a 200 amp main interrupt. Technically this would be a violation of standard procedure. the 200 amp fuse protects the 2/0 feeds to the panel, but if you use 2 or 4 wire to connect the inverter they will be way over their capacity at 200 amps! You need a fuse to protect the feeds to the inverter that will break at their ampacity. If you were to short the inverter feed, 2 or 4 wire will burn up before the 200 amp link interrupts the feed.

Put in a cartridge fuse at the max ampacity of the feed. That would be 130 or 95 amps respectively for 2 or 4 gauge wire. Code allows you to round up to the next available fuse or breaker size.

That is unless you meant 2/0, which can carry 195 amps (hence the 200 amp disconnect)

Pretty easy to do and won't cost much.

Scott

Re: Wiring a 2nd inverter

Reply #2 –
Yahoo Message Number: 88840
I have a second inverter I installed in my 99 Allure. I have a dishwasher and a induction cooktop that do not like the modified sinewave that is produced by my low frequency Heart 2000. I used the xantrex sw 2000 pro watt that are selling everywhere. I also used the transfer switch and remote sold for use with it. I had to do some looking to find the transfer switch but they are out there and sold for use with the pro-watt series. My Heart inverter charger has a 15 a branch that feeds the utility circuits comprised of all outlets except for microwave leg. The Heart 2000 in the inverter bay has 3 identified connections on the front under a connection cover. They are labeled and composed of an input from ac power distribution panel and 2 outputs, 1 12-2 20a fused microwave feed (goes to outlet above microwave in kitchen) and 1 14-2 15a fused feed that sources all other utility outlets thru the gfi receptacle in bedroom. This is where I installed my transfer switch. I obtain shore power from the input to the Heart 2000 from ac distribution panel and provide to the transfer switch input. The output of switch is connected to the 14-2 15 amp utility feed (existing connection to Heart output is removed and Heart output left disconnected ) The transfer switch comes with a 15a plug to use with the sw 2000 and just plug in to gfi outlet on inverter. I connected my sw 2000 to batterys using the same size wiring used by country coach for the Heart in fact my unit had about 4 times as much wire coiled up in the inverter box as needed so I just shortened the heart wiring and used for sw2000 after installing new lugs. Both inverters share common ground and I used the existing 350a fuse not expecting to ever draw more than 350 amps dc even with 4000 watts inverter capeability. Operation is seamless with sole change being the second inverter control switch installed near refer in coach. I only turn on the Heart inverter function for microwave use although it still performs the battery charge duties when generator or shore power connected. The advantage to using sw 2000 is lower idle current on it than the Heart. I have had this installed for about 6 months and living in Alaska have many hours on system as dry camping is normal here. I have a 400ah agm battery pack monitored with a trimetric and 600w of non-tracking solar fed thru a Rogue MPPT controller. You may wonder why I didn't just go with a 2000w pure sine wave inverter replacement, I prefer the Heart for charging duties and the old Heart 2000 is a bulletproof MSW inverter that has a heavy duty transformer output proven reliable. I was initially skeptical of the reliability and performance of the sw 2000 as it is the "new" xantrex and a high frequency design. It has performed well with a clean sinusoidal outpur and will run all my sinewave sensitive equipment. I purchased the sw2000 for 230.00 on e bay and paid 30.00 for the remote and 75.00 for the transfer switch. This was considerably less than I could have purchased a Magnum 2000 for. The electral schematics in your CC books will show you how the Heart is wired and I recommend you update the schematic showing inclusion of the second inverter.

David White 99 Allure #30349

Re: Wiring a 2nd inverter

Reply #3 –
Yahoo Message Number: 88843
Hi David - Came very close to doing the second PSW inverter too. Our 2003 era Trace/Xantrex 2000W (think it's the RV2012 or RV2014)with the added Echo charge has had a good reputation too.
I went back and forth on this, before going ahead and swapping out to a Magnum ME2800 PSW, and all of the related sub components.
Two downsides to this from my viewpoint: 1) The addition of second smaller stand alone PSW for a few circuits, would have provided some form of 'redundancy' in case one of the inverters failed. So one instead of two inverters is that downside. 2) The idle usage is just a tad bit more then the Magnum 2000W version. But the combined idle of the Trace/Xantrex 2000W and the second smaller PSW I was considering was a tad bit more then the single Magnum PSW 2800W.
I'm a fan of KISS, and so the less complexity of one inverter vs two inverters was a key nod to the Magnum ME2800W PSW decision. The other key factor, probably the main reason for 'one vs two' inverters. Is that the charging settings available on the Magnum series of components, was much more supportive of our AGM's. (We just added 800AH's of Lifelines.)
The ME2800 vs ME2000 was to allow for my HiFi (Got Tubes) hobby. May never need the extra capacity, but the 'head room' allows future proofing of power consumption. (We remain with the Norcold 1200, with the Amish Cooling unit installed. So no plans on residential Samsung mod.)
I added this to your thread your post, to provide 'thinking material' for others that review this thread. Each of us have different needs, and approaching things from different angles is what it is all about.
Best to all, and pardon the pun 'May the power, both PSW and MSW, be with you!:)' Smitty

04 Allure 31017
04 Allure Sold to a nice new owner! Now enjoying a 07 Magna Rembrandt 45' ISX600 #6775
"We're ONDROAD for THEJRNY!" (Toad and Coach license plates, say Hi if you see us!)

Re: Wiring a 2nd inverter

Reply #4 –
Yahoo Message Number: 88870
Thanks for the feedback everyone. David, like you, I decided to go this route because partly because of the economics. $350 vs $2000+. Also the lower overhead of the smaller 1000w inverter. I have the following components arriving on Monday (BTW, beside having great prices, Hodges Marine upgraded the shipping to overnight, at their expense, when I casually mentioned that I was behind schedule).
http://www.hodgesmarine.com/Xantrex-Prowatt-Sw1000-1000w-True-Sinewave-Inverte-p/xan806-1210.htm?click=19 http://www.hodgesmarine.com/Xantrex-Remote-Panel-W-25-Cable-For-Prowatt-Sw-I-p/xan808-9001.htm http://www.hodgesmarine.com/Xantrex-Inline-Transfer-Relay-F-Prowatt-Sw-p/xan808-0915.htm
My coach differs a bit from the wiring David describes. A 2/0 gauge wire runs from the house batteries to a 200 amp DC breaker, all in the rear of the coach. A 2/0 gauge wire then runs to a house battery disconnect relay in the electrical compartment in the front of the coach. On the other side of the relay, a short 2 gauge wire runs to a 105 amp DC breaker. On the other side of the breaker, two 2 gauge wires exit. I'm pretty sure one goes to the generator, not sure about the other one. I followed it for a little bit, but got lost in a huge cluster of wires. Any ideas on what this wire would be for? To power the inverter, it seems I could use a 2/0 gauge wire of I want to tap into the house battery disconnect relay, or 2 gauge wire if I tap into the 105 DC breaker. I guess it would be possible to trip this breaker if I start the generator while the small inverter was turned on. I can live with turning the inverter off before starting the generator if need be. In this same electrical compartment up front, there is a 2 gauge ground wire that goes from the frame to a ground buss bar. The buss bar has about 20 smaller ground wires connected to it. I was thinking I would use this same frame location for the inverter negative connection. Did I forget anything on the DC side? Does all this sound correct?
Now to the AC side. My Freedom 25 is located in the rear bay of the coach, not far from the house batteries. The Freedom has only 1 output instead of 2. The output has a 30 breaker. This output is connected to a subpanel located at the front of the coach near the electrical compartment.. The subpanel has 2 AC breakers, both 20 amps. One is for the microwave, one is for the outlets. The inputs on these 2 breakers are connected together with a jumper wire.
My plan is to leave the 20 amp breaker and wiring for the microwave as-is, remove the jumper wire, and replace the outlet breaker with a 15 amp breaker. The transfer switch has 2 inputs, a priority and a non priority (not sure what the correct terminology is). I would wire the priority input to the output of the new inverter and non priority input to the output of the Freedom. Then the output of the transfer switch to the 15 amp breaker for the outlets. This way I could still use some the Freedom to power the outlets in the rare circumstances when I need the extra power. When I plug into shore power, I will have to manually turn off the small inverter, but I'm ok with that. Also, the new inverter has a AC ground terminal that I would just attach to the same ground location (frame) that I used for the DC negative connection. Does this sound like it would work? Thanks again for the feedback.

Jim

99' Magna #5629