Inverters Magnum or Xantrex

[TomCat]

If you do decide on the Magnum, I have a brand new one in the box that I will sell for $1,875.00 plus shipping.

I paid a little less than that for a new Xantrex RS3000, Control Panel , and Auto Gen Start Module. Shipped.
All works as advertised nearly two years after install.

Jay
87 SaftLiner

[Nick Badame Refrig/ACC]

I'm going to post the spec charts on some brands.
I also have the RS3000, and the 3 year warranty tops most others.
Nick-


   
RS3000 Sine Wave Inverter/Charger
Designed for RVs to power advanced onboard electronics. The RS3000 features 3000 watts of sine wave output and an advanced three-stage battery charger together with industry-standard networking capability.




Model
RS3000 SW Inverter/Charger 



   
Product Info | Specifications | Document Downloads | Compare 
 
Specifications


Electrical Specifications - Inverter


Output power (continuous)
 
3000 watts


Surge rating (5 seconds)
 
7500 watts (60 A)


Output voltage
 
120 VAC


Output frequency
 
60 Hz +/- 0.05% (crystal controlled)


Output waveform
 
Sine wave (< 5% THD)


Peak Efficiency
 
> 90%


Efficiency (full load)
 
> 85%


No load power draw (search mode)
 
< 20 W


AC connections
 
Split phase in / dual out, Dual in / dual out


AC transfer capability
 
2 legs at 50 A (split phase in),
2 legs at 30 A (dual in)


Transfer time
 
20 ms (typical)


Electrical Specifications - Charger


Output current
 
150 A DC


Battery voltage (nominal)
 
12 VDC


Battery voltage range
 
10.0 - 15.5 VDC


Charge control
 
3 stage with manual equalize


Charge temperature compensation
 
Remote battery sensor (included)


Efficiency
 
85% typical


AC input power factor
 
0.95


Input current (for 150 A charging)
 
22 A RMS nominal


AC input voltage
 
120 VAC nominal


AC input voltage range
 
90 - 135 VAC


Compatible battery types
 
Wet/Gel/AGM


General Specifications


Operating temperature range
 
-4°F - 122°F (-20°C - 50°C)


Storage temperature range
 
-40°F - 122°F (-40°C - 50°C)


Dimensions (HxWxD)
 
8.17 x 13.25 x 16" (208 x 336 x 406 mm)


Weight
 
75.0 lb (34.0 kg)


Warranty
 
3 years


Part number
 
809-3000 (Split phase in / Dual out)


Accessories
 
System Control Panel

Automatic Generator Start


Regulatory Approvals
CSA/NRTL certified to CSA 107.1, UL 458
FCC Class B/Industry Canada Class

[Nick Badame Refrig/ACC]

Here's the 4024


SW2512MC & SW4024MC2
Widely used throughout the world as a primary source of AC electricity, the SW offers sine wave, utility grade output power, high capacity battery charger, high surge current ability (inrush current), and easy installation.



   
Product Info | Specifications | Document Downloads | Compare 
 
Specifications Available
SW2512MC
SW4024MC2


SW2512MC


Electrical Specifications


AC input voltage
 
120 VAC


AC input voltage range
 
80 - 149 VAC


AC input current
 
60 amps AC pass thru 30 amps AC charging (Required for full pass through and full charging)


Continuous Power @ 25°C
 
2500 VA


Efficiency (Peak)
 
90%


AC output voltage (RMS)
 
120 VAC


AC output voltage regulation
 
+/- 5%


Frequency
 
60 Hz


Waveform
 
Sine wave, 34 - 52 steps per cycle


Total harmonic distortion
 
< 5%


Continuous output @ 25°C
 
21 amps AC


Surge capability:
 
 


5 sec rating (resistive)
 
4000 watts


1 mSec
 
65 amps AC


100 mSec
 
46 amps AC


Automatic transfer relay
 
60 amps


DC input voltage (Nominal)
 
12 VDC


DC input voltage range
 
11.8 - 16.5 VDC


DC current at rated power
 
275 amps


Idle consumption
 
< 16 watts Typical at Full Voltage


Search mode consumption
 
< 1 watt


Max. charge rate (adjustable)
 
150 amps DC at 12 V nom.


General Specifications


Specified temperature range
 
32°F - 77°F (0°C - 25°C) Power derated about 25°C


Enclosure type
 
Indoor, ventilated, steel chassis with powdercoat finish


Unit weight
 
90 lb (41 kg)


Shipping
 
96 lb (45 kg)


Inverter dimensions (H x W x D)
 
15 x 22.5 x 9" (38 x 57 x 23 cm)


Shipping dimensions (H x W x D)
 
15 x 27 x 21" (38 x 69 x 53 cm)


Mounting
 
Bulkhead mount


Warranty
 
Two years


Part numbers
 
SW2512MC


 
 
SW4024MC2


 
 
SWRC (SW remote control panel with LCD and 25' cable for SW4024MC2 and SW2512MC)


 
 
SWRC/50FT (same as above but with 50' cable)


Regulatory Approvals


cETL approved to UL 1741, UL 458, and CSA 107.1




SW4024MC2


Electrical Specifications


AC input voltage
 
120 VAC


AC input voltage range
 
80 - 149 VAC


AC input current
 
60 amps AC pass thru 30 amps AC charging (Required for full pass through and full charging)


Continuous Power @ 25°C
 
4000 VA


Efficiency (Peak)
 
94%


AC output voltage (RMS)
 
120 VAC


AC output voltage regulation
 
+/- 5%


Frequency
 
60 Hz


Waveform
 
Sine wave, 34 - 52 steps per cycle


Total harmonic distortion
 
< 5%


Continuous output @ 25°C
 
33 amps AC


Surge capability:
 
 


5 sec rating (resistive)
 
8000 watts


1 mSec
 
110 amps AC


100 mSec
 
78 amps AC


Automatic transfer relay
 
60 amps


DC input voltage (Nominal)
 
24 VDC


DC input voltage range
 
22 - 33 VDC


DC current at rated power
 
200 amps DC


Idle consumption
 
< 16 watts Typical at Full Voltage


Search mode consumption
 
< 1 watt


Max. charge rate (adjustable)
 
120 amps DC at 24 V nom.


General Specifications


Specified temperature range
 
32°F - 77°F (0°C - 25°C) Power derated about 25°C


Enclosure type
 
Indoor, ventilated, steel chassis with powdercoat finish


Unit weight
 
105 lb (48 kg)


Shipping
 
111 lb (50 kg)


Inverter dimensions (H x W x D)
 
15 x 22.5 x 9" (38 x 57 x 23 cm)


Shipping dimensions (H x W x D)
 
15 x 27 x 21" (38 x 69 x 53 cm)


Mounting
 
Bulkhead mount


Warranty
 
Two years


Part numbers
 
SW2512MC


 
 
SW4024MC2


 
 
SWRC (SW remote control panel with LCD and 25' cable for SW4024MC2 and SW2512MC)


 
 
SWRC/50FT (same as above but with 50' cable)


Regulatory Approvals


ETL approved under standard UL458

[Nick Badame Refrig/ACC]

Magnum/Outback don't let you copy/print their specs so, here is the link
Nick-


http://www.magnumteknologies.com/

[Sean]

In dealing with alot of refrigeration compressors, ... when voltage drops, why does the amp draw increase.
...
How do theese motors know to try and keep a certain rpm?

Nick,

There are two basic types of AC motors (OK, I know electrical-engineer types can dispute this, as there are many variations on these today).

The first type, which is common in, for example, electric drills, is called a universal motor and is wound just like a DC motor, with slip-rings and commutators.  These motors behave more or less like a resistive load -- if you reduce the voltage, you will reduce the power and speed of the motor.  The advantage is that it is easy to control the speed, as it is a direct function of voltage, and it's not sensitive to line frequency.  Also, it can be used on AC or DC.

The second major type is the synchronous motor.  This motor will turn at a speed that is a direct function of the AC line frequency.  Almost all three-phase motors are synchronous, and it is very easy to build a synchronous motor when you have three phases available.  Basically, the motor has three (or multiples thereof) windings that are offset from each other by 120 degrees, and as each phase voltage peaks in its respective winding it will attract the corresponding pole of the rotor (overly simplistic, but that's the basic idea).

A single-phase synchronous motor presents special challenges.  Something must be done to create a "phase offset" to set up a moving magnetic field for the rotor to follow in order to get the rotor moving.  There are several techniques... low torque motors such as table fans use what is known as a "shaded pole" and high torque motors such as your compressors generally use a technique involving a start-up winding called "split phase."  The start-up winding gets cut out of the circuit once the motor has reached synchronous speed by a centrifugal switch.  Starting torque can be increased and/or starting current reduced in a split-phase motor through use of a "start  capacitor".

In any case, one thing all synchronous motors have in common is that once running, the nature of electromagnetic force causes the motor to resist any force that would cause the rotor to fall out of synch with the AC current frequency.  The further out of synch you try to push the rotor, the greater the motor will try to resist, and the current in the windings will increase to achieve this.

Any load on the motor is a force trying to drag the rotor out of synch, so current in the windings will increase to compensate.  And, as we discussed, if the load on the motor is constant, and the AC frequency is constant, but the voltage drops, then current will also increase to compensate.

Here are a couple of sites that go into much more detail on how AC motors work:
http://www.coolmagnetman.com/magacmot.htm
http://en.wikipedia.org/wiki/AC_motor

Incidentally, one thing that helps tremendously in a situation where you need to run an A/C on perhaps marginal park power, is to use a bigger cord.  Every wire has a voltage drop across it that is related to length, but larger gauges have less drop.  So when we are someplace where we have access only to, for example, a 15-amp circuit, but we need to run one A/C (running load of about 13 amps, once started), we forgo our 50', 10-gauge shore cord and haul out the big guns -- our 25' 6-gauge shore cord, with a dogbone on the end to connect to the 15-amp outlet.  If we need more length, we add our 40' 6-gauge extension cord.  Even though it's only carrying 15 amps, having the 6-gauge really cuts down on the voltage drop.

-Sean
http://ourodyssey.blogspot.com

[Sean]

Magnum/Outback don't let you copy/print their specs so, here is the link

http://www.magnumteknologies.com/

Actually, that's (confusingly) a different "Magnum."  Who also sells inverters, but not the sine-wave model we have been discussing.  The correct link is:

http://www.magnumenergy.com

-Sean
http://ourodyssey.blogspot.com

[DrivingMissLazy]

I am just moving this topic to the top so I do not lose it. I am going to have to take exception to Shawn's description of motors and I want to really think about it long and hard before I do so. LOL
Richrd

Magnum/Outback don't let you copy/print their specs so, here is the link

http://www.magnumteknologies.com/

Actually, that's (confusingly) a different "Magnum."  Who also sells inverters, but not the sine-wave model we have been discussing.  The correct link is:

http://www.magnumenergy.com

-Sean
http://ourodyssey.blogspot.com

[Sean]

I am just moving this topic to the top so I do not lose it. I am going to have to take exception to Shawn's description of motors and I want to really think about it long and hard before I do so. LOL

See, I told you the electrical-engineer types would dispute it 

Richard, I did say that I was glossing over a lot of stuff...  I did not want to launch into a full-scale discussion of inductance, reluctance, magnetic flux, and the phase of the moon  .  Which is why I put the links in to basic motor technology sites.

But if I really got something wrong (as opposed to just really oversimplified), do let me know....

-Sean
http://ourodyssey.blogspot.com

[Busted Knuckle]

I am just moving this topic to the top so I do not lose it. I am going to have to take exception to Shawn's description of motors and I want to really think about it long and hard before I do so. LOL
Richrd

Magnum/Outback don't let you copy/print their specs so, here is the link

http://www.magnumteknologies.com/

Actually, that's (confusingly) a different "Magnum."  Who also sells inverters, but not the sine-wave model we have been discussing.  The correct link is:

http://www.magnumenergy.com

-Sean
http://ourodyssey.blogspot.com

Couldn't ya look at how his name is spelled correctly while ya contemplating picking his post apart!

[Nick Badame Refrig/ACC]

Hi Sean,

Thanks for all the information.

I'm a little more clear on the split phase and shaded pole motors now...  Maybe thats why I find terminals burnt up on compressors

that have either locked rotar or lost it's start windings. I'm gonna read thoose links you posted some more.

Thanks Again
Nick-

[Stan]

I also advise to use adequate wire size but your example is a little extreme. Using the calculator on this link, shows a voltage drop of .66 volts on 50' of #10 at 13 amps. I don't think this will have significant effect on motor current.

http://www.stealth316.com/2-wire-resistance.htm

[DrivingMissLazy]

I am just moving this topic to the top so I do not lose it. I am going to have to take exception to Shawn's description of motors and I want to really think about it long and hard before I do so. LOL
Richrd

Magnum/Outback don't let you copy/print their specs so, here is the link

http://www.magnumteknologies.com/

Actually, that's (confusingly) a different "Magnum."  Who also sells inverters, but not the sine-wave model we have been discussing.  The correct link is:

http://www.magnumenergy.com

-Sean
http://ourodyssey.blogspot.com

Couldn't ya look at how his name is spelled correctly while ya contemplating picking his post apart!

If you look close BK, you will note that I misspelled my name also. Since today is my 52nd wedding anniversary I will blame the errors on that. LOL
Richard

[Sean]

...your example is a little extreme. Using the calculator on this link, shows a voltage drop of .66 volts on 50' of #10 at 13 amps...
http://www.stealth316.com/2-wire-resistance.htm

Umm, I think the calculator on that link is for 12VDC.  That's not the right formula for 120VAC.  Also, while the A/C has a running load of 13A, the coach will be drawing 15A, the rated capacity of the circuit.  When I run the numbers, I get a drop of 1.6%.

That is within acceptable tolerance, however, I was talking about a situation where the park voltage was marginal to begin with.  So if you had only, say, 110 volts at the pedestal, now you'll have 108 (or maybe much, much less -- see below).  You are right, that won't have too much effect on compressor running current (an extra .2 amp from the draw at the nominal rating of 120 volts), but it is, in my experience, a noticeable difference.  And, with only ~2 amps left over to run everything in the coach, including the battery charger, that .2 amp represents 10% of the available capacity.

By contrast, 25' of 6-gauge is a drop of only 0.3%, less than a fifth the drop of my 10-gauge cord.

The numbers get much more definitive at higher currents.  I can use the 10-gauge cord set on a 30-amp circuit as well, and I often do (although I also often dial the draw back down to 20 amps).  At a 30-amp draw, the drop on 50' of #10 rises to 3.1%, considered just out of the acceptable range.  If I have a solid 120VAC at the pole, I don't worry too much that I'll be getting only 116 in the coach.  But if I have only 110 coming in, that will drop to 106.6, again a noticeable difference.

Remember, also, that voltage drop is current dependent.  So when you take your (almost zero current) DVM to the pedestal and measure, say, 115VAC, you may not realize that the 30-A circuit on that pedestal runs back to the main panel on perhaps 100' or more of #10.  So now my 50' cord is making a run of 150' on #10 wire, for a whopping 9.3% voltage drop (104 volts at the coach) on a 30-amp draw, or 4.7% on a 15-amp draw (109.6 volts).  There is not much you can do about the gauge and length of the wire from the main to the pedestal, but you can at least minimize the additional drop in your additional cord.

YMMV.

-Sean
http://ourodyssey.blogspot.com

[DrivingMissLazy]

Sean and all, In my experience, the majority of motors (excluding the hand tool motors) are asynchronous as opposed to synchronous.

Three phase Synchronous motors are designed to run at a specific speed (rpm) regardless of input voltage or the connected load, as long as these items are within the operating parameters of the motor.

For example, a four pole synchronous motor, connected to a 60 hertz power source will rotate at exactly 1800 rpm +-0 from no load to full load. Typically it will stay locked in up to 150% load and with input voltage varying as much as 20% or more. With a properly adjusted exciter, the power factor will be 1.0 pf. This means that every amp going into the motor is being converted to watts. If the excitation is increased the pf will go leading and the motor will began acting as a synchronous condenser and this phenomenon is utilized by many large companies to try and correct their normal lagging power factor, since the utility company penalizes companies for having a poor (lagging) power factor.

In my experience, less than 1% of all the 3 phase motors in existence are of the synchronous type. In fact they were so scarce that in the 70's I had to develop (invent) a method of converting a synchronous alternator into a synchronous motor in order to have a supply of motors to build the power converters I was manufacturing for the main frame computer market place.

Many years ago these motors were used in large conveyor systems to maintain  the synchronous speed of various production lines but I believe the advent of the easily controlled Variable Frequency Drive Systems driving asynchronous motors  have replaced  the synchronous motor.

The only other place that I am aware of this type motor being used is in the electric wall clock. Did anyone ever wonder why they keep such accurate time?

It is because the driving motor is a synchronous motor which is locked to the frequency of the utility power grid it is connected to.  Additionally the entire power grid in the US is tied together so that phase A of the power in California is exactly in step with phase A in Maine.

Even further, the grid is so regulated that every night just before midnight the overall US grid is tweaked up or down, as necessary to make sure that the correct  number of cycles have occurred within the past twenty four hours. And that boys and girls is why our wall clocks are so accurate. 

The asynchronous motor is the workhorse of the industrial world and is more commonly referred to as an induction or squirrel cage motor. Its RPM is always less than the synchronous speed would be.

For example, a four pole induction motor, connected to a 60 hertz power line will operate at approximately 1790 rpm at no load and 1750 rpm at full load. The actual rpm depends on the quality of the motor and the design. Some are designed to be low slip, and some are designed to be high slip.

I could probably continue on for many pages, but have tried to limit this to the minimum that would get my opinion across.
Richard

[Sean]

Richard,

My brain must be addled -- of course you are right, I left out the third and most common type of AC motor, the induction motor.  And, of course, the compressor motors Nick was asking about are likely induction motors.  Always good to have a real heavy-duty-power guy around to set me straight.

The answer about the current is still the same -- any effort to resist the magnetic force trying to pull the rotor forward will be met with increased current in the windings.

Squirrel-cage rotors are also one of the possible mechanisms for starting synchronous motors until they reach synchronous speed.

-Sean
http://ourodyssey.blogspot.com