RayTek MARATHON FA - Air Purge Collar; Protection Tube

Accessories
MarathonSeriesFA/FR 35
8.2AirPurgeCollar
TheAir PurgeCollar accessory is used to keepdust, moisture,airborneparticles,andvaporsaway
fromtheopticalheadʹslens.Itcanbeinstalledbeforeorafterthebracket.Itmustbescrewedinfully.
Airflowsintothe1/8”NPTfittingandoutthefrontaperture.Airflow
shouldbeamaximumof0.5‐
1.5liters/sec(1‐3cfm). Clean(filtered)or“instrument”airisrecommendedtoavoid contaminants
fromsettlingonthelens.Donotusechilledairbelow10°C(50°F).Alsoprovidedisastainlesssteel
protectiontube,150mm(6inches)longby25mm
(1inch)diameterthatthreadsontothefrontofthe
airpurgecollar.

Figure31:AirPurgeCollarandProtectionTube(XXXFOHAPA)
8.3ProtectionTube
The protection tube is available as an accessory. It is305 mm (12 in.) long and 32 mm (1.26 in.) in
diameterandcomeswith¾”NPTexternalthreadatoneend.Theopticalheadisthreadedwiththe
protectiontube.Theuseoftheairpurgecollarinthesame
timeispossible.

Figure32:ProtectionTubeforOpticalHead