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Old September 25th 08, 01:13 AM posted to rec.radio.amateur.homebrew
[email protected] jimmie68@gmail.com is offline
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First recorded activity by RadioBanter: Dec 2007
Posts: 78
Default microwave oven inverter P.S. revisited

On Sep 21, 10:03*am, Grumpy The Mule wrote:
The designer of this power supply did something very wrong.
Using the safety/chassis ground as a power connection to
run 120V loads is dangerous. *If you need to power 120V
loads run a neutral line or use a 240/120 transformer.

Safety ground should only be connected to the chassis,
faraday screens and Y-rated capacitors.

Neutral and safety ground eventually tie together so
it seems like an OK thing. *It's not. *It's a violation
of the NEC, any applicable safety standards and might
on the off chance cause serious injury or death.



==============http://www.realhamradio.com/hvreg.pdf- Hide quoted text -


- Show quoted text -


I never saw where the neutral and ground tied together. The closest
thing I could see was on the HV side of the transformer where one side
is tied to ground. This is OK. I did find in another service manual
where it warned about not having the mounting screws to the power
supply fastened tightly while servicing. Thats almost funny. Probably
a good idea to use this on a GFCI circuit.

Anyway I came across some 120/240 to 240/480 volt 2KVA transformers I
had. This got me thinking that it may be at lot of fun building a
switcher when you had 600VDC at a few amps to switch. Coming up with a
transformer may be fun.

Jimmie