SMN 9-60

Which parameters define its operation?

The electrical rating places this lamp between low-current indication types and higher-output optical lamps. A 625-hour reference life is specified for nominal operation; overvoltage can shorten it and change brightness. The electrical rating should be considered together with light output and operating duty. Overvoltage raises filament temperature and will normally shorten service life.

How is the lamp constructed and installed?

The 3.2 mm envelope and special base form a very short assembly approximately 9 mm long. This version installs in a compatible miniature holder. SMN 9-60-2 uses flexible leads and is mechanically different despite matching voltage and current. Before installation, compare bulb diameter, overall clearance and the exact connection method. The lamp must not be forced into an unsuitable holder, loaded through the glass envelope or fitted by changing the original mounting arrangement.

Where is this execution used?

Lamps in this group are used for local indication and illumination inside compact instruments, annunciators and illuminated controls. Installation in a particular aircraft, helicopter, panel or instrument must be confirmed by the applicable parts list or equipment documentation. The SMN or MN family name alone does not establish aircraft applicability.

How should the correct lamp be selected?

Use SMN 9-60 only where the holder, supply and required light output match. When replacing an old lamp, compare the suffix, base and overall length as carefully as the voltage marking. Related products on the card help compare nearby executions in the same narrow subgroup; they do not establish automatic interchangeability. An enquiry should include the marking of the removed lamp, circuit voltage, holder or lead type and the required quantity.