5 Oct
1997
5 Oct
'97
3:11 a.m.
Sam Ismail wrote:
Today at a local flea market, I picked up a PRO (Made in Taiwan) Soldering
Iron Controller. It has a three-prong power outlet and a heavy duty
potentiometer for controlling the voltage level of the outlet.
The labeling indicates "MAX. 800 WATTS-120 V.A.C." My math tells me that
this unit can handle a maximum of 6 amps. Would this be safe to use as a
variac on, say, a sparsely loaded IMSAI?
It was only a buck.
Sam Alternate e-mail: dastar(a)siconic.com
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Hi Sam:
Safe??? --- That's a loaded question.
Consider the differences in output ---
The 'Variac' (or equivalent variable transformer), will be putting out a
comparitively _clean_ 'sine wave'. (It will even have filtered out
_soome_ of the garbage that is on the normal 110v AC line.)
The 'Soldering Iron Controller', is _probably_ an SCR and control
circuits. The output of that will be a _very_ chopped up AC (I.E. the
wattage control, is varying the 'turn on point' during the AC cycle to
control the effective power.)
The 'Soldering Iron Controller', is suitable for _resistive_ loads, that
don't care about the wave form of the incoming power. I.E. soldering
irons, light bulbs (but NOT fluorescent fixtures), lightly loaded
_universal_ motors.)
Chuck
--
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He, who will not reason, is a bigot; William Drumond,
he, who cannot, is a fool; Scottish writer
and he, who dares not, is a slave. (1585-1649)
While he that does, is a free man! Joseph P. 1955-
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Chuck Davis / Sutherlin Industries FAX # (804) 799-0940
1973 Reeves Mill Road E-Mail -- cad(a)gamewood.net
Sutherlin, Virginia 24594 Voice # (804) 799-5803