FYI The Magnum Inverter/Chargers are very good but cost tradeoffs in the design were made. I discovered the following on my ME2012 (2KW inverter and 100A charger) and these cost tradeoffs were made across the product line with variations for various models. Magnum has confirmed my findings.1. The units require 120V at the AC input terminal (not somewhere else in the rig) before they will charge at the maximum rate. For example my unit with 116V on the input has a maximum charge rate of 80% or 80A. 2. The DC amp display is estimated on the AC input current and not on the actual DC current. For example my unit will display 100A when in fact it is charging at 80A. 3. A battery voltage sense for the charger capability is not possible. Magnum suggested that I could install their battery monitor which includes a DC shunt to get accurate readings for #2. My battery monitor already had more capability.

Magnum is not TRACEThis is not the 1990's, labor, material and taxes are cruel in the USA todayA really nice 2,500 watt inverter charger would cost $5,000.00 USD.A really nice inverter charger would include a TWO HUNDRED AMPERE rated high frequency charger protected against under frequency, and would have simple adjustments to tweak stage voltages and time retained at end of stages. Two optional temperature sensing inputs, selectable and freakin' ADJUSTABLEKeep dreaming

I don't know if price equals quality in the inverter/charger market but Mastervolt makes standalone 100A charger (ONLY does charging) for nearly the same price as Magnum's PSW 2kW inverter/charger. About the same physical size too. Does weigh less though.

I see the Mastervolt 100amper goes to 14.4 then drops to 14.25 for four hours.

The portable Honda gen puts out over 120v but some rigs have those built- in gens with dirty output that reads low like MSW in a way, so not so good with that charger (and some other chargers too).Mex mentions a variable voltage feature not being included ( one of the trade offs?) but is there an external gizmo you can put in there that is not too expensive or awkward? Mex often mentions a Variac?? (whatever, don't know them.)

BFL13 wrote:I see the Mastervolt 100amper goes to 14.4 then drops to 14.25 for four hours.It's adjustable up to 15.5V. All of the stages are adjustable up to 15.5V. Also, has timer settings for each stage up to 8 hours each I think. VARIAC's adjust 120V up or down. Something like that should work to bring the charge voltage up.

Magnum Inverter/Charger Design Tradeoffs | Good Sam Community

mena661
Explorer
Sep 30, 2013
CA Traveler wrote:
Another surprise to me was the high standby current (0.25A) with no shutoff capability.
Actually, that's not bad. My 300W draws the same amount. The Victron inverters of the same wattage as the Magnum draws more in standby.
CA_Traveler
Explorer III
Sep 30, 2013
Another surprise to me was the high standby current (0.25A) with no shutoff capability. This adds up to 180AH/month in storage unless there is a disconnect switch.

Today's electronics only use a few milliamps of power in off/standby operation.
CA_Traveler
Explorer III
Sep 30, 2013
BFL13 wrote:
Does the Variac's voltage adjustment make up for the poor wave form of the built-in gen being the cause of the apparent lower voltage? IE, even with a higher voltage, would it still be a poor wave form, so the charger still would not do full amps?
Since it's a basic autoformer I would expect minimum wave form change.
mena661
Explorer
Sep 29, 2013
BFL13 wrote:
Does the Variac's voltage adjustment make up for the poor wave form of the built-in gen being the cause of the apparent lower voltage? IE, even with a higher voltage, would it still be a poor wave form, so the charger still would not do full amps?
Don't know about that one. I would think not but not well versed in the VARIAC's.
BFL13
Explorer II
Sep 29, 2013
Does the Variac's voltage adjustment make up for the poor wave form of the built-in gen being the cause of the apparent lower voltage? IE, even with a higher voltage, would it still be a poor wave form, so the charger still would not do full amps?
mena661
Explorer
Sep 29, 2013
BFL13 wrote:
I see the Mastervolt 100amper goes to 14.4 then drops to 14.25 for four hours.
It's adjustable up to 15.5V. All of the stages are adjustable up to 15.5V. Also, has timer settings for each stage up to 8 hours each I think. VARIAC's adjust 120V up or down. Something like that should work to bring the charge voltage up.
BFL13
Explorer II
Sep 29, 2013
The portable Honda gen puts out over 120v but some rigs have those built- in gens with dirty output that reads low like MSW in a way, so not so good with that charger (and some other chargers too).

Mex mentions a variable voltage feature not being included ( one of the trade offs?) but is there an external gizmo you can put in there that is not too expensive or awkward? Mex often mentions a Variac?? (whatever, don't know them.)
BFL13
Explorer II
Sep 28, 2013
I see the Mastervolt 100amper goes to 14.4 then drops to 14.25 for four hours.
mena661
Explorer
Sep 28, 2013
I don't know if price equals quality in the inverter/charger market but Mastervolt makes standalone 100A charger (ONLY does charging) for nearly the same price as Magnum's PSW 2kW inverter/charger. About the same physical size too. Does weigh less though.
MEXICOWANDERER
Explorer
Sep 28, 2013
Magnum is not TRACE

This is not the 1990's, labor, material and taxes are cruel in the USA today

A really nice 2,500 watt inverter charger would cost $5,000.00 USD.

A really nice inverter charger would include a TWO HUNDRED AMPERE rated high frequency charger protected against under frequency, and would have simple adjustments to tweak stage voltages and time retained at end of stages. Two optional temperature sensing inputs, selectable and freakin' ADJUSTABLE

Keep dreaming

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