IEC 60869-1 :2018 pdf download – Fibre optic interconnecting devices and passive components – Fibre optic passive power control devices – Part 1: Generic specification.
3.1 .6 optical power limiter fibre optic passive power control device that regulates the optical power in fibres, producing a controlled, constant optical output power of optical limit power, as a result of varying optical input power higher than the input optical limit power 3.1 .7 plug-receptacle style device fibre optic device having a combination of two interfacing features, a plug at one end and a receptacle at the other 3.2 Performance terms 3.2.1 optical fuse power threshold P th optical input power, into an optical fuse, in which the optical output power is blocked Note 1 to entry: The optical fuse power threshold P th is expressed in watt or dBm. 3.2.2 optical fuse response time time between the start of the input power and the end time when the output optical power has decreased to be less than the predetermined optical power Note 1 to entry: The predetermined power shall be either of the power threshold, P th minus insertion loss, IL, (P th − IL) in dB, or the input power, P in minus the required blocking attenuation at threshold, A block . Note 2 to entry: The optical fuse response time depends on the optical input power level and the input pulse time. Note 3 to entry: An example of the input power, P in , is recommended to be 3 dB over of the power threshold, P th , and the rectangle shape pulse of 1 ms (P in = P th + 3 dB). An example of the required blocking attenuation at threshold, A block of 30 dB is recommended. 3.2.3 optical fuse blocking attenuation at threshold A block drop in optical power through the optical fuse when exposed to more than the optical fuse power threshold P th , with response by blocking the power, expressed in dB 3.2.4 optical power limiter response time length of time between the start of the input power and the end time in decreasing the output power to be less than or equal to the predetermined power
3.2.1 0 maximum attenuation <for variable optical attenuator> attenuation of the maximum value which is set 3.2.1 1 minimum attenuation <for variable optical attenuator> attenuation of the minimum value which is set 3.2.1 2 attenuation setting resolution minimal adjustable step size or difference of the attenuation of a VOA Note 1 to entry: This term is applicable only to VOAs. 3.2.1 3 error of setting value of attenuation difference between the insertion loss of the device at a given setting and nominal attenuation Note 1 to entry: This term is applicable only to VOAs. 3.2.1 4 repeatability of setting attenuation value maximum deviation of the insertion loss of the device at a given setting in multiple times of repeated settings Note 1 to entry: This term is applicable only to VOAs. 3.2.1 5 maximum allowed power input maximum input power that the device can handle without causing malfunction or permanent damage, expressed in watt or dBm Note 1 to entry: This term is applicable to all fibre optic passive power control devices. Note 2 to entry: This term is equal to optical fuse power threshold to optical fuse. Note 3 to entry: The maximum input power defined in IEC TS 62627-09 has a different meaning of the maximum input optical power for which a passive optical device keeps the required optical performances.
There are two types of optical attenuator: a fixed optical attenuator and a variable optical attenuator. The power reduction rate of a fixed optical attenuator is constant. The performance curve of a fixed optical attenuator is shown in Figure 1 , where the attenuated power is always lower than the non-attenuated power and proportional to it. Annex E describes the fixed optical attenuator application note as a users’ guide.