How-To Geek: Be Careful Before Running Your Computer From a Gas Generator
The web site How-To Geek has long been a useful resource. Last week they published an article entitled, “Be Careful Before Running Your Computer From a Gas Generator.” Given our experience during the Great Texas Freeze of 2021 this hits close to home. It’s a reasonable article overall, but it has a couple of holes that I’d like to fill.
Mr. Butler is absolutely correct, a traditional generator can be a problem when running sensitive electronics like computers or TVs. We discovered this in February 2021 when our reasonably new furnace would not run reliably on the generator. I would not have guessed that a gas-fired furnace would present a problem. However, the electronically controlled, variable speed blower struggled to start when connected to the dirty and lumpy generator power.
He suggests using a UPS to protect your sensitive devices from the generator. That’s a nice idea, but there is some subtlety to that as well. The type of UPS matters.
Uninterruptible Power Supplies (UPS)
Our older, admittedly inexpensive, line-interactive UPSs absolutely freaked out when connected to generator power. They saw the variability in the generator output as something to be corrected, but way beyond their scope. They reacted very badly, cyclically putting backup power in/out of circuit every couple of seconds.
However, as with most low-cost UPSs, it was “line-interactive” design. In such a design the power provided by the batteries and invertor is connected in parallel to the utility power. When utility power falters the local circuitry tries to make up the slack. The design is simple. Any UPS under $500 new is almost certainly a line-interactive design.