What will a ‘mod­i­fied’ in­verter power?

Canal Boat - - Technical - STEVE MITCHELL, via email TONY REPLIES…

QI am a lit­tle con­fused over what equip­ment can be used with a mod­i­fied sine wave in­verter. With a true sine wave in­verter, I as­sume that any 240v equip­ment can be used.

Things seem, how­ever, a lit­tle sketchy on a mod­i­fied sine wave. In some places people say they are fine to run pretty much any­thing. While other places say they can­not be used with in­duc­tive loads.

Un­for­tu­nately, the an­swer is far from clear cut. The term MSW (mod­i­fied sine wave) seems to be ap­plied to in­vert­ers that pro­vide from an al­most square wave through to a trape­zoidal wave form, so one may op­er­ate cer­tain equip­ment with­out a prob­lem while an­other could de­stroy equip­ment.

As an ex­am­ple, it has been re­ported that some ex­pen­sive elec­tric tooth­brushes and hair stylers have been de­stroyed by MSW in­vert­ers while cheaper ver­sions have seemed to work fine. Like­wise, it also seems that some MSW in­vert­ers ap­pear to run mains lap­top power sup­plies well but it is re­ported that, in some cases, the power sup­plies run hot and the elec­tri­cal con­sump­tion is more than ex­pected. It is well known that items with elec­tronic timers are likely to have prob­lems with MSW in­vert­ers so that rules out most mi­crowaves and wash­ing ma­chines etc. Drills and san­ders will prob­a­bly run well enough but might be noisier than usual and run hot, es­pe­cially if they have speed con­trols. My view is that, if you want an in­verter for more than very light and oc­ca­sional power use, you would be bet­ter off pay­ing the ex­tra for a pure sine wave in­verter be­cause that should run any­thing you or vis­i­tors re­quire it to (within its power rat­ing).

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.