Simple Energy-Saving Switch Schematic Diagram
Don’t do not always need to be on at full power. Often it would be useful to be able to turn off the more powerful lights to realize softer illumination, but this requires an installation with two separately-switch-able circuits, which isn’t always available.
Energy-Saving Switch Circuit Image
If the trouble of chasing out channels and replastering for an entire new circuit is an excessive amount of, then this circuit might help. Normal operation of the light switch gives gentle illumination (LA1). For more light, simply turn the switch off and then immediately (within 1 s) on again. The circuit returns to the gentle light set-ting when switched off for more than 3 s. There is no have to replace the light switch with a dual version: simply insert this circuit between switch and lamp.
Energy-Saving Switch Circuit Diagram
R1 = 100br> R2 = 680br> Capacitor:
C1 = 4700µF 25 V
D1,D2 = 1N4001
K1,K2,K3 = 2-way PCB terminal
block, lead pitch 7.5 mm
F1 = fuse, 4AT (time lag) with PCB
TR1 = mains transformer, 12V @ 1.5
VA, short-circuit proof, PCB mount
B1 = B80C1400, round case (80V
RE1 = power relay, 12V, 2 x c/o,
RE2 = miniature relay, 12V, 2 x c/o,
How does it work?
Almost immediately after switch-on, fast-acting miniature relay RE2 pulls in, since it is connected directly after the bridge rectifier. Its nor-mallyclosed contact then isolates RE1 from the supply, and thus current flows to LA1 via RE1’s normally-closed con-tact. RE1 doesn’t have time to tug in as it is a power relay and thus relatively slow. Its response can be slowed down by the point constant of R1 and C1. If the present through the light switch is briefly interrupted, RE2 drops out immediately. There is enough energy stored in C1 to activate RE1, which then holds itself pulled in via a second, normally-open, contact. If current starts to flow again through the light switch within 1s, LA2 will light. To change LA1 back on it is critical to turn the light switch off for greater than 3 s, in order that C1 can discharge via R2 and RE1. The printed circuit board can be built right into a well insulating plastic enclosure or be incorporated right into a light fitting if there’s sufficient space.
the printed circuit board is connected on to the mains-powered lighting circuit. Every precaution must be taken to forestall touching any component or tracks, which carry dangerous voltages. The circuit should be built right into a well insulated ABS plastic enclosure.