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Kudos to you ricardocello for being aware of this issue and doing something about it!! You understand the design deficiency and are taking action!! The capacitor ripple current ratings effect on life are specified at the maximum rated ambient temperature. If your ambient temperature maximum is...

In agreement, the inverter is rated for 5000VA and operating a load with 0.8PF would yield 4000W. However, the cert. specifies 33A AC which yields 3960VA (just under 4000) at 120V AC. The cert. specification for output current is not specific to any PF and is therefore assumed to be 1.0 (unity)...

The cert. specifies 33A AC Output. 120V x 33A = 3960VA, not 5000VA. What is up with that?

It would be an interesting exercise to compare the MK3 reading with calibrated lab test equipment. Of course, the inverter does not have direct access to the voltage ripple present on the battery terminals.

I have finally come to the realization the MP II 5kVA 48V inverter is really a 4kW inverter before we derate it's output power due to ambient temperature and power factor. Consider 40C ambient operation with a PF of .60, this will give you a 2220W inverter. A PF of .6 is not unreasonable for...

The root cause is that an AC voltage provider demands current from its source that is directly related to the instantaneous power delivered throughout the entire sine wave cycle. This is an inherent characteristic and the only way to deal with it is filtering. One system design option is to...

Yes, there is a very large empty volume in the bottom of the 5kVA 48V Multiplus II UL unit. I would add as many large Aluminum electrolytic capacitors in there across the 48V input bus that would fit without severely blocking airflow. On one of the reviews (Current Connected) commented on not...

I am familiar with the "H bridge" topology. It is the ideal circuit to synthesize a sinewave in the positive and negative polarity. The FETs are controlled from a high frequency PWM that is fed from a sine reference signal. As the output voltage rises up the sinewave, the on duration of the FETS...

Given the situation, it is best to keep the battery cables as short as possible, positive and negative conductors adjacent and touching - twisted is best. This will help to reduce radiation and minimize inductance. Be aware this ripple current will be imposed on the battery as a ripple voltage...

I guess if there are no input capacitors in the design then "they" will not wear out due to excessive temperature or ripple current. From an engineering standpoint not the way I would handle it. Does Victron engineering ever post on this forum?

To state this in another way; For the 5kVA Multiplus II feeding a purely resistive load (PF = 1.0) will it deliver 5000W? If so, then it must be delivering; 5000 / 120 = 41.67A RMS.