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Reviews Categories | Emergency/Portable Power: generators, solar, wind, thermal, etc | Sima STP-325 325 watt Power Inverter Help

Reviews Summary for Sima STP-325 325 watt Power Inverter
Reviews: 1 Average rating: 4.0/5 MSRP: $59.99
Description: Smooth start technology to smoothly bring up the AC power helps protect the unit plugged into the inverter and the inverter
Product is in production.
More info: http://
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KE3Y Rating: 4/5 May 7, 2007 20:31 Send this review to a friend
Versatile, fan can be made cyclic with work  Time owned: more than 12 months
Easily handles a computer, monitor, and several ham radio accessories. No RF noise is generated while idling or in use. The fan runs continuously and the noise is unpleasantly noticable, as with most of these things. The load may be grounded. Compare my review of the Xantrex Xpower 700 Plus. Currently available at

For modifying the inverter fan to run intermittently, there is a temperature-dependent voltage at a transistor collector nearest the on-board Sonalert. (7V Cool; 4.5V Sonalert alarm; 4.2V is shutoff.) I use a complicated 3-IC circuit with a 555 driving the fan. The fan runs rarely with a small (~100W) load. You could try mounting on the heat sink a snap thermostat in series with the fan, like the Stancor Disc Thermostat that closes between 113 and 127 degrees F. and open when it cools 10 degrees (Mouser # 802-STC-120). However I suspect a lower and tighter range might be needed.

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