Installing inverter, keep converter?

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Karl said:
Terry and Mark, From the dimensions of the new Xantrex inverter, you'll probably have to mount it external to the existing distribution box anyway, so that will probably leave enough room for a small, separate breaker box for the fridge and a/c as Terry suggested. Or make sure the fridge and a/c are each on their own circuit breaker in the existing box, mark them as "a/c Shore power only" and Fridge Shore power only" and flip them to the "OFF" position unless you are hooked up to shore power.
Click to expand...

Hi Karl:

Thanks for the reply.  Actually, I plan to put the inverter under the couch, which is where the converter currently is.  There's plenty of room, and it will keep the wiring short and simple.


Mark

 
Mark,
That should simplify things quite a bit. Just make sure the positive and negative from the battery(ies) to the inverter a large enough for the full inverter load. The existing converter wiring may not be sufficient. Size of wire depends on inverter wattage and distance to the batteries. Let us know, and we can help determine the proper size. You may not have to replace the existing wiring, but run another positive/negative pair in parallel with it. As long as you're doing rewiring, I'd suggest installing a GFCI outlet (or two) in the coach if it doesn't already have it. Determining which outlet(s) should have it is a little tricky as one GFCI can protect multiple outlets, but we can help with that too. 
 
It should be simple...    Just connect the inverter/charger to the battery(ies) with adequate sized wire, and turn off the converter circuit breaker in the magnatek front panel.  That will leave all the DC circuits connected to the battery (through the various fuses).  The inverter will provide DC power as well as charging the battery when connected to shore power.  What you do with the inverter output is up to you... you may want to connect up to existing wiring, but an isolation relay will be required.
Art
 
What you do with the inverter output is up to you... you may want to connect up to existing wiring, but an isolation relay will be required.
Click to expand...
We usually call those "transfer switches", and depending on make and model, will be included in the inverter itself. The model Xantrex he quoted does already have it. It will automatically switch from inverter power to shore power when present.
 
If you can simply turn off the converter's power source with a circuit breaker as King describes, that makes everything easy. No need to worry about supplying power to the DC portion of the Magnetek, because it is already wired to the battery 12V system. The Xantrex will supply power to the battery via the Xantrex 12V leads and from there the power will reach the Magnetek panel through its existing battery/12V connection. You only have a problem if for some reason you have to cut the 12V supply to the Magetek panel. but it sounds as though that is not necessary.
 
The Xantrex should be connected directly to your batteries using LARGE wires.  Check the current requirements of the inverter - under full load it will almost certainly draw more current than the existing 12 volt battery wires can handle.  The Xantrex's  converter will also charge the batteries using these same wires when you're hooked up to AC power.

Disconnect the Magnetek's AC input.  There is a black wire going to a 120 volt circuit breaker and a white wire going to the 120 volt neutral buss.

At this point the batteries (and the Xantrex that is charging them) will feed all of your house 12 volt circuits, just as they do when you are boondocking.  However, there is a DC relay inside the 6300 that can become problematic.  It would be best to remove the Magnetek entirely from the circuit.

The 6300's 12 volt fuseboard is divided into two busses, since the 6300 has two 12 volt outputs.  The main unfiltered output feeds the majority of the fuses and a secondary low current filtered output charges the battery and feeds sensitive circuits like the TV outlet.

Locate the converter's two (+) 12 volt output lines - they should go to large terminals on the 12 volt fuseboard.  Disconnect them and then jumper the two (+) 12 volt terminals together.  This connect all of the 12 volt circuits to the batteries.
 
Thanks Karl, Gary, and Lou -- appreciate you sharing your experience and expertise.  I was planning on replacing the battery cables, so that one is covered.  And after kicking around the various options, I think I'll probably just yank the whole Magnetek unit out and replace it with an Iota IDP 30 amp AC/DC panel, as it will mount in the same area.  In fact, I'll probably put two of the Iota panels where the Magnetek was -- one for inverter items and the other for non-inverter (AC, maybe the microwave) items.  The Iota panels are fairly inexpensive, and it will certainly be cleaner and probably easier just to use them rather than reusing the AC & DC distribution panels in the Magnetek.

Thanks again for the help and advice.  It's too darn cold here (Ohio) to be messing around with RV projects right now, but I'll post a follow-up once I get started.


Mark
 
From everything I have read on the nets about Magnetek so-called converters (they are not converters, just battery chargers) the very best thing you can do with one is yank it out.  So I'd say you have a good plan.

If your inverter is a good Emergency power type unit like my prosine 2.0 (Xantrex) which can also charge batteries, maintain them and otherwise do what is needed, you need not replace the Magnetek at all, you can let the inverter's charger section do the work.

Or, if you like I recommend any converter which uses, or has built in, the Charge Wizard 3-stage charger controller.  My Progressive Dynamics 9180 with Charge Wizard is fantastic, Treats the batteries well, does everything needed without me even looking at it, and what's more in my first year of ownership I added water once, at the 1 year point, (I check the batteries often but it took a full year before I felt the need to add any and it was not even close to urgent) 

Another question is "Should I leave the rig plugged in when parked"  Answer if you have a Magnetek is NO,  With my PD 9180 the answer is YES,  Again, this is the fault of the charge wizard controller so your IOTA, which I believe either has one built in or as an optional add on... Should be a good choice

My rig is on shore power over 40 weeks a year,  The rest of the time it's either on the road again, or, Well, I spend a couple weeks boondocking every year (No shore power, No water, No phone, No cable, No sewer, about a dozen high speed internet connections to choose from... You can tell what we here in the forum call IMPORTANT can't you,, It's a forum rally)
 
John In Detroit said:
From everything I have read on the nets about Magnetek so-called converters (they are not converters, just battery chargers) the very best thing you can do with one is yank it out.  So I'd say you have a good plan.
Click to expand...

I've had Magnetek's in all 5 of my various rigs over the past 10 years -- and they have all worked as advertised. They not only trickle charge my batteries, they "convert" AC from shore or Genset to DC. Isn't that why they call it an converter? :)

My "poor man's inverter/charger system" consists of a 1500W StatPower Inverter and a Statpower 40A 3 stage charger. Separate units. I purchased them shortly after buying my first RV in '95 -- and have reinstalled them in 4 rigs after that including my current rig. Here's the process:

o Install the charger on a rig bulkhead and plug it into a nearby AC power switchable power source. Connect proper sized battery leads to the house batteries. The only time I turn it on is when I am recharging my house batteries while boon docking.

o Install Inverter on a bulkhead beside the charger. Connect proper sized DC input wires to the house batteries.

o Connect proper sized AC wiring from Inverter to Converter. This involves installation of a double pole double throw switch. I have used both auto and manually switched. Input to be switched comes from Shore/Genset on one pole and from Inverter on the other -- whereas the output from the switch feeds the AC source to the converter.

The most inexpensive way to do this to buy 2, 30A (my rigs have all been 30A) switches, turning one upside down beside the other one - then connect the two throw levers with a metal dowel. This way, when one is turned on, the other one is turned off at the same time. I really liked that because I could switch from Genset to Inverter without having to turn any AC device off (such as my computer or TV). My current DPDT is an auto switching unit with a 20 second pause when switching from one source to the other.

o My system then becomes "breaker/power strip controlled". When I go to Inverter power, I turn all breakers off that I don't need. That includes the breaker that controls the Converter Charger. As mentioned earlier in this thread, I never want to be charging batteries while on Inverter power. DC now comes directly from my batteries as needed. Other breakers turned off control the Air, Microwave, or any section of the coach I am not in need of wall outlets. This plus power strips allows me to control phantom loads such as the power a printer or TV pulls even though turned off.

When on shore power the process is reversed. For example, my Inverter and 3 stage charger are then shut down completely. If boon docking, when the Genset is on, the 3 stage charger is also on. When on Shore Power, the rig operates soley via the Converter until I have need to go to Inverter power. I monitor the system with a Trace Meter (Wally Installed, of course ;)). This allows me to know where every tenth of an amp is coming from while on Inverter power.

May one day install a larger system that would replace my Converter -- but for now, I enjoy spending those bucks on other toys. :)
 
Well Bob, it is possible that Magnetek makes some good units, I don't know.  I do know that every one I've read about was unregulated.

This means that if you plug in to shore power for, oh, say 3 months, while the rig is in storage,  It's gonna harm your batteries cause it does not know when to stop charging.  And as you said it is a slow charger 230 AH at 20 AMP is a long time charging.

230 at 80 amps is a lot faster charging and with proper regulation does no harm to the battery as it tapers off when the charge gets up there.  Trickling to zero amps when it's full up. 


Now, for some time I've used a battery charger coupled with a 12 volt car battery to run some radios.  Works great, but w/o the car battery it don't work well... Not well at all.  (Loud hum in radio)

The difference between a converter and a battery charger is the output waveform.

My Progressive dynamics has a output waveform that is rather close to a very flat line.... Battery chargers I can't draw with ASCII but imagine these are prens on their side instead of top-hats

It is either ^^^^^^ or ^ ^ ^ ^ ^ ^ and it relies on the battery to smooth it out so my radio could use it
 
A full-wave rectifier (four diodes in a bridge arrangement) will produce the same output waveform regardless of it being a converter or a battery charger. The difference is in the output filtering (i.e. smoothing capacitor(s)). All things being equal, the battery is irrelevant; it's just another big capacitor.
 
Hey John:

>> Well Bob, it is possible that Magnetek makes some good units, I don't know.  I do know that every one I've read about was unregulated.
====
As I write this, the charger portion on my converter is feeding 1.1amps to my batteries -- not 20amps. Have been parked w/full hookups for about a week, so that's all it needs to keep them topped off. Not sure what your source is, but it does not apply to the Magnetek's I have had for the past 10 years in 5 rigs.

Am a full timer so I never put my rig into storage.

>> The difference between a converter and a battery charger is the output waveform.
====
I don't think so - unless I misinterpret what you write. A converter has A/C input from either Shore/Genset OR an Inverter in my case. The rig needs DC to run most systems plus to charge the batteries. So that is what a converter does. It "converts" a portion of the AC coming in to DC for those 2 chores. The charger portion of a converter will have different wave forms according to the manufacturer. But a converter is not a charger. A converter "contains" a charger.

When I am on Inverter power, I throw the breaker that disables my converter. Then there is no conversion of the AC. It just goes through the breaker panel and throughout my rig -- and the DC for the rig comes from the batteries. So charging is not happening during my inverter usage.
 
The Magnatek uses a regulating transformer that maintains the converter output at the 12Vdc average.  The charge output is the same 12Vdc average, but it actually has an almost 17 V peak.  The charge circuit shuts off when the battery voltage reaches a preset voltage.  The one I have only charges at about a 6 A rate, so it's very slow to charge.  It also seems to be set at too high a reference voltage, since it will cause the batteries to use water.  I usually depend on the chassis alternator to charge the house batteries.  I turn off the Magnatek for storage...  turn it on for a day or two about once a month, or use a separate charger to be sure the batteries are fully charged.
Art
 
King said:
The charge circuit shuts off when the battery voltage reaches a preset voltage.   The one I have only charges at about a 6 A rate, so it's very slow to charge.
Click to expand...

Art, the specs on my converter indicate a .5amp average charge rate. The current set of house batteries have been in there for about a year now and I have not had to add water as yet. There "is" an adjustment for the charging rate, but I read it is best to have an authorized person do that if needed. I sure would not want to mess with it. Because the charger hums when it is on, I can tell that when I am doing my normal stuff, it is off most of the time.

There is an upgrade to Magneteks such as mine (6345) with a much higher rated 3 stage charger. You just slide out the bottom half of the current converter, and slide in the replacement. I thought about it, but decided to stay with the current arrangement for now because I already have a StatPower 40A three stage that I use when boon-docking to get the batteries back up each day. If I ever had need to store my rig, I would shut down the Magnetek and use the Statpower charger to keep the batteries topped off.
 
So King what you are saying is the Magnatek has dual outputs, one filtered and regulated one not filtered and poorly regulated.

As i said, My Progressive dynamics My radios can not tell it from a battery, and they are very senesitive

I'm not sure you can say that about a Magnatek, From everything I"ve read, you can't
 
Hi John -

Yes, the older 6300 series Magnetek has two outputs.  A main output that is full wave rectified but unfiltered and isolated from the battery so it's cycling from 0 to +17 volts.  Plus a secondary, filtered and regulated output that's limited to 5 or 10 amps and has to not only charge the battery but power sensitive stuff like the TV outlet.

The 12 volt DC fuse board is likewise divided into two busses, filtered and unfiltered.  The converter has an internal open frame relay that parallels both busses when the unit is unpowered so everything can run off the battery.  When you plug in, the relay energizes and seperates the busses so the battery is only connected to the filtered side.  As you might expect, this relay tends to be trouble prone, which is why it is a good idea to completely remove the converter from the circuit instead of just removing the AC supply.

The unfiltered power shortens the life of the water pump and fan motors.  DC motors really don't like running on unfiltered power.  Tends to shorten brush life and make interesting wear patterns on the armature.  The life of fluorescent tubes and their ballasts are likewise shortened.

I like to salvage the transformer from discarded 6300 series converters.  The price is right (haul it away!) and a little creative wiring makes it into a dandy boost transformer for low park voltage.
 
Thanks Lou,  From what I keep reading however they tend to overcharge batteries and boil them dry unless, as in Bob's case you keep a reasonable load on them.  My progressive Dynamics does not do that.  I'm currently (just for the heck of it) monitoring battery voltage using an test device I often use in my car.  It is indicating (As I sit here) just very very slightly higher than normal loaded battery voltage.  When I first plug in it indicates normal alternator output voltage

Normal alternator voltage would be bulk or absorption modes, Normal battery voltage is "Float" (stage 3) and the very slightly higher means that the converter is providing the power instead of the battery so the battery is at "no-load" potential
 
I guess You misunderstood my comments.  The regulation in the magnatek is due to the ferroresonant transformer used.  It provides a relatively constant AC voltage out for a wide range of input voltages.  It is then full wave rectified to provide a half sine ripple which when averaged produces 12Vdc.  It is not good for electronic appliances which need a cleaner dc power.  This is the 12Vdc output to selected coach loads as well as the output to charge the house batteries. The charger output is turned off when the batteries reach a preset voltage.  The output to the remaining loads (electronic) is connected to the batteries. There is no DC filtering in either output, as the batteries act as the filter.
Art
 
Ok if there is no DC filtering then it's not a converter  but a battery charger, which is what I said to begin with that you argued with

Convertes convert 120vac to 12vdc (or perhaps 13 or 14 or some other DC voltage)

Battery chargers charge batteries and let them run the down stream electronics

I've done it both ways  by the way

As for the output being limited so the batteries don't overcharge and boil dry

I have heard from many folks who's batteries boiled dry, nearly all had Magnatek  chargers
 
King - what model Magnetek do you have?  I think we are talking about two different devices because the 6300 series does not have a ferroresonant transformer.  Instead it relies on a small circuit board to regulate it's low currentfiltered output and leaves the majority as raw, unfiltered power.
 
You must log in or register to reply here.

Latest posts

Members online

Total: 751 (members: 24, guests: 727)

Forum statistics

Threads
131,964
Posts
1,388,325
Members
137,718
Latest member
urnwholesaler
Back
Top Bottom