Even the promising and the most talked about LED technology is perhaps unable to produce lights equal to the modern electronic flourescent ballasts lights. The circuit of one such electronic flourescent ballast is discussed here, with efficiency better than LED lights.
The complete building procedure and information regarding how to make an Electronic Fluorescent Ballast is enclosed HEREIN.....
Care should be taken to avoid using it with high current load. Otherwise, suitably modify the relay for higher currents. The stability of voltage limits depends mainly on the potentiometers. Use good-quality potentiometers, either cermet or wirewound types. Do not try to usethe usual trimpots instead. » EI
When matched units ate found, check the match at minimum RDS = +0.5V) and at 10 times this
with only fuse protection, it is better to connect the thyristor across the un- regulated supply as shown in Fig.2 to prevent damage to the regulator circuit when the crowbar operates.
The error rises at low frequencies, somewhat below 5A useful fea- ture is that the unit can be powered by the same supply as the one supplying the circuit under test.
A typical set of values for lm = %Amp is Vz = 3V, R = 1% ohms.
The load current is limited by the relay contact ratings.