Re: Pure sine wave. Drives the AC
Reply #5 –
I would assume that under a heavy load the inverter is toasty hot? My limited knowledge of those inverters would lead me to think that if it's 85% efficient that that's it's getting really hot. Maybe/probably derating internally? Maybe try a cooling fan on it just to test.
As an example my looking at various inverter/chargers when i was replacing my Heart freedom 2500 original equipment unit the various available units varied in many ways. Some valued effeciency hence using smaller physical sized transformers and cooling fans and areas internally where there operating systems monitored temps and weighed x amount.
Other units valued higher continuous power output with a much heavier internal transformer setup and larger cooling fans.
Your unit uses transistors as I understand to convert 12 volt into 120 volt. Hence the lighter weight and potentially a different ability to large large percentages of its rated output for longer times.
Early 2000 unicoaches had their heavier transformers inverter/charger mounted on the rear vertical wall of the last compartment and had added a vertical mounted cooling fan that blew air over the inverters cooling air input area to assist their inverters cooling not to derate.
Not sure how that fan was triggered. My inverter/charger has a dedicated separate output to power an external whatever separate from its normal output in either 12v ot 120v.
My inverter and most of the similar upper 50 pound weight various manufacturers inverter/chargers used dual transformer coils and dual variable speed ball bearing cooling fans internally and had multiple internal monitoring areas to monitor various internal component temps. If they were getting too hot they would increase their internal cooling fans speeds and if the heating increased they would start to derate their output.
Maybe an external additional cooling fan would allow a large load for longer term?
I am thinking that your large load on your unit maybe causing the unit to output lower voltage as it's derating method?
Second thought was to run its output into a Hughes autoformer as it will take 109 volts and through its windings in its potted transformer loops change low voltage back to 120 volts. Versus low voltage shore power the same idea could restore a low voltage output inverter I assume.
I maybe incorrect in how your inverter is constructed and how it works but in the rest of the inverter/chargers I researched they varied internally in their designs where some favored efficiency and reduced their internal component sizes and cooling system and other used much heavier internal components and cooling capacities to be able to put out larger loads for longer times in warmer operating conditions without derating.
Some inverters have fairly minimal indication on their operating panels that they are derating. Warning lights.
Others show the actual amount.
Cooling fan seems easy. Foretravel added a panel mounted external cooling fan system to its heavy transformer and cooling fan inverter/chargers to lessen derating under hot conditions and heavy loading.
Topic: Pure sine wave. Drives the AC