Forum Discussion
CA_Traveler
Mar 06, 2018Explorer III
125ADC is indeed 125A DC. But read the Magnum spec carefully. Several that I've looked at indicated they reach the rated output ONLY when the AC input is 120V at the Magnum terminals. Mine rated at 100A only produces 80A at 117V input.
Furthermore amps for the charger first supply house loads and THEN the remaining amps charge the battery. Your battery monitors with shunts right on the battery indicate the actual battery amps in or out.
And a caution for those with a Magnum and no battery monitor. When I found out my unit was only charging 80A maximum the display (no BMK) was showing 100A. How can this be? So I started preparing to take the unit to Magnum for repair.
A phone call revealed that a 80A output at 117V AC input was by design. Furthermore the 100A DC output display when the output was 80A was also by design. You see they don't actually measure the DC amp output but rather calculate it based on the AC input - that is not a typo.
The other limiting design is the lack of a remote voltage sense capability. So the charger/inverter has no knowledge of the actual battery voltage.
While the 5 stage Magnum charging is excellent the unit does have "cost/design" compromises as confirmed in my phone call to them.
Furthermore amps for the charger first supply house loads and THEN the remaining amps charge the battery. Your battery monitors with shunts right on the battery indicate the actual battery amps in or out.
And a caution for those with a Magnum and no battery monitor. When I found out my unit was only charging 80A maximum the display (no BMK) was showing 100A. How can this be? So I started preparing to take the unit to Magnum for repair.
A phone call revealed that a 80A output at 117V AC input was by design. Furthermore the 100A DC output display when the output was 80A was also by design. You see they don't actually measure the DC amp output but rather calculate it based on the AC input - that is not a typo.
The other limiting design is the lack of a remote voltage sense capability. So the charger/inverter has no knowledge of the actual battery voltage.
While the 5 stage Magnum charging is excellent the unit does have "cost/design" compromises as confirmed in my phone call to them.
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