Delmar
Solar Addict
I don’t know how I missed this UPS porn thread. I have been messing with APC UPSverters and have learned a few expensive things:
* Many consumer grade UPSs are modified sine. You have to research the model number to determine. Many will have a distortion warning molded into the case.
* The UPSs are sensitive to elevated battery voltage, like charging from solar with minimal loading.
* Most of the small UPSs are designed to overheat soon after the internal battery dies. For temperature protection some will shutdown on time & loading, and ignore the available battery voltage.
* Good APC UPSs are low-frequency and great for starting motors. To get the equivalent LF inverter would require 10x the cost. However the downside are the UPSverters are not very efficient, especially at low loading. And loud with multiple fans that run regardless of loading, and big LF transformers emitting a 60hz hum.
To ensure you are getting a pure sine UPS that is rated for continuous operation, I look for APC “XL” models. They are easy to spot in auction pictures by the rear external battery connector. Below are pics of my 24V 1000XL running my moms TV, and my 3000XL powered by my 48V golf cart and back-feeds my breaker panel during grid down. The HF unit on the far right ignored the extended battery and shutdown on time & loading.
* Many consumer grade UPSs are modified sine. You have to research the model number to determine. Many will have a distortion warning molded into the case.
* The UPSs are sensitive to elevated battery voltage, like charging from solar with minimal loading.
* Most of the small UPSs are designed to overheat soon after the internal battery dies. For temperature protection some will shutdown on time & loading, and ignore the available battery voltage.
* Good APC UPSs are low-frequency and great for starting motors. To get the equivalent LF inverter would require 10x the cost. However the downside are the UPSverters are not very efficient, especially at low loading. And loud with multiple fans that run regardless of loading, and big LF transformers emitting a 60hz hum.
To ensure you are getting a pure sine UPS that is rated for continuous operation, I look for APC “XL” models. They are easy to spot in auction pictures by the rear external battery connector. Below are pics of my 24V 1000XL running my moms TV, and my 3000XL powered by my 48V golf cart and back-feeds my breaker panel during grid down. The HF unit on the far right ignored the extended battery and shutdown on time & loading.
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