Electric Wiring, 3rd Edition

54 Wiring lighting points

P.F.

CAPACITOR

CHOKE

TUBE

PEN

J«

P.F.

CAPACITOR

HH

J||

CHOKE

3jgj[Z]=B TUBE EtJ

2 PIN SWITCH AND SOCKET

WITH R. I. S. CAPACITOR

4 PIN SWITCH AND SOCKET

WITH HEATER COIL

Fig.

4.15. A glowswitch automatic starter circuit (left) and a thermal switch starter

circuit (right)

When the circuit switch is closed, full mains voltage is applied across the

starter switch, and this causes a glow discharge to be set up across the open

contacts. The discharge heats the bi-metallic strips and thus causes the switch

to close. As soon as the switch closes, current is applied to the cathodes which

produces the pre-heating mentioned earlier ...