Printed version of this standard is available at Library. To request, please e-mail to referencepk@usm.my and include a copy of this record in your e-mail.
This British Standard specifies d.c. and single-phase a.c. automatic double-pole change-over contractors for low voltages up to 250 V employed in conjunction with storage batteries or other alternative source of supply, to provide a means of automatically changing the current supplied to safety light from normal source fails, and of reconnecting the safety lights to the normal source when this source is restored.