From: "petrus bitbyter"
Subject: Re: neon lamp query
X-Newsreader: Microsoft Outlook Express 5.50.4807.1700
Date: Wed, 18 Sep 2002 14:41:15 GMT
NNTP-Posting-Date: Wed, 18 Sep 2002 16:41:15 MET DST
Organization: chello broadband
Most of that type of neon bulbs strikes at 90VDC/65VAC. Continuous current
is 0.5 to 1mA at a lower then the strike voltage p.e. 70VDC at 1mA. So for a
220V mains, start with a 330kOhm, 0.25W seriesresistor. If you have light
enough, keep it this way. Otherwise you can lower the resistor keeping an
eye on the current by measuring the voltage of the resistor.
"bc" schreef in bericht news:firstname.lastname@example.org...
> I have a query about neon lamps; in particular, those little bulb neons we
> use as indicators that the mains electricity supply is on.
> I have a collection of these things and I want to use one as a mains
> indicator on a prototype project. I need to use a dropper resistor, but
> size? This is a heterogeneous collection of neons and they may well have
> quite different striking voltages. I can pick one and find its approximate
> strike voltage using a charged-up 400V capacitor and a very large dropping
> resistor. But to calculate the final dropping-resistor size, I need to
> the size of the continuous current that these things are expected to
> on; is it about 1mA or nearer 50?
> How much is too much?
> Please email any answers
> Regards Bruce